From fa6d79fb1344c10aabe6606c13fee8f8aba8d1b4 Mon Sep 17 00:00:00 2001 From: "Ryan C. Gordon" Date: Wed, 19 Aug 2009 00:39:47 -0400 Subject: [PATCH] Forgot to add GLU sources to revision control. --- GLU/dict-list.h | 100 ++++ GLU/dict.c | 111 ++++ GLU/dict.h | 100 ++++ GLU/geom.c | 264 ++++++++ GLU/geom.h | 84 +++ GLU/gluos.h | 72 +++ GLU/memalloc.c | 55 ++ GLU/memalloc.h | 54 ++ GLU/mesh.c | 789 ++++++++++++++++++++++++ GLU/mesh.h | 266 +++++++++ GLU/normal.c | 253 ++++++++ GLU/normal.h | 45 ++ GLU/priorityq-heap.c | 253 ++++++++ GLU/priorityq-heap.h | 107 ++++ GLU/priorityq-sort.h | 117 ++++ GLU/priorityq.c | 260 ++++++++ GLU/priorityq.h | 117 ++++ GLU/render.c | 498 ++++++++++++++++ GLU/render.h | 52 ++ GLU/sweep.c | 1357 ++++++++++++++++++++++++++++++++++++++++++ GLU/sweep.h | 77 +++ GLU/tess.c | 628 +++++++++++++++++++ GLU/tess.h | 165 +++++ GLU/tessmono.c | 201 +++++++ GLU/tessmono.h | 71 +++ GLU/util.c | 90 +++ 26 files changed, 6186 insertions(+) create mode 100644 GLU/dict-list.h create mode 100644 GLU/dict.c create mode 100644 GLU/dict.h create mode 100644 GLU/geom.c create mode 100644 GLU/geom.h create mode 100644 GLU/gluos.h create mode 100644 GLU/memalloc.c create mode 100644 GLU/memalloc.h create mode 100644 GLU/mesh.c create mode 100644 GLU/mesh.h create mode 100644 GLU/normal.c create mode 100644 GLU/normal.h create mode 100644 GLU/priorityq-heap.c create mode 100644 GLU/priorityq-heap.h create mode 100644 GLU/priorityq-sort.h create mode 100644 GLU/priorityq.c create mode 100644 GLU/priorityq.h create mode 100644 GLU/render.c create mode 100644 GLU/render.h create mode 100644 GLU/sweep.c create mode 100644 GLU/sweep.h create mode 100644 GLU/tess.c create mode 100644 GLU/tess.h create mode 100644 GLU/tessmono.c create mode 100644 GLU/tessmono.h create mode 100644 GLU/util.c diff --git a/GLU/dict-list.h b/GLU/dict-list.h new file mode 100644 index 0000000..11331a7 --- /dev/null +++ b/GLU/dict-list.h @@ -0,0 +1,100 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __dict_list_h_ +#define __dict_list_h_ + +/* Use #define's so that another heap implementation can use this one */ + +#define DictKey DictListKey +#define Dict DictList +#define DictNode DictListNode + +#define dictNewDict(frame,leq) __gl_dictListNewDict(frame,leq) +#define dictDeleteDict(dict) __gl_dictListDeleteDict(dict) + +#define dictSearch(dict,key) __gl_dictListSearch(dict,key) +#define dictInsert(dict,key) __gl_dictListInsert(dict,key) +#define dictInsertBefore(dict,node,key) __gl_dictListInsertBefore(dict,node,key) +#define dictDelete(dict,node) __gl_dictListDelete(dict,node) + +#define dictKey(n) __gl_dictListKey(n) +#define dictSucc(n) __gl_dictListSucc(n) +#define dictPred(n) __gl_dictListPred(n) +#define dictMin(d) __gl_dictListMin(d) +#define dictMax(d) __gl_dictListMax(d) + + + +typedef void *DictKey; +typedef struct Dict Dict; +typedef struct DictNode DictNode; + +Dict *dictNewDict( + void *frame, + int (*leq)(void *frame, DictKey key1, DictKey key2) ); + +void dictDeleteDict( Dict *dict ); + +/* Search returns the node with the smallest key greater than or equal + * to the given key. If there is no such key, returns a node whose + * key is NULL. Similarly, Succ(Max(d)) has a NULL key, etc. + */ +DictNode *dictSearch( Dict *dict, DictKey key ); +DictNode *dictInsertBefore( Dict *dict, DictNode *node, DictKey key ); +void dictDelete( Dict *dict, DictNode *node ); + +#define __gl_dictListKey(n) ((n)->key) +#define __gl_dictListSucc(n) ((n)->next) +#define __gl_dictListPred(n) ((n)->prev) +#define __gl_dictListMin(d) ((d)->head.next) +#define __gl_dictListMax(d) ((d)->head.prev) +#define __gl_dictListInsert(d,k) (dictInsertBefore((d),&(d)->head,(k))) + + +/*** Private data structures ***/ + +struct DictNode { + DictKey key; + DictNode *next; + DictNode *prev; +}; + +struct Dict { + DictNode head; + void *frame; + int (*leq)(void *frame, DictKey key1, DictKey key2); +}; + +#endif diff --git a/GLU/dict.c b/GLU/dict.c new file mode 100644 index 0000000..49d4f75 --- /dev/null +++ b/GLU/dict.c @@ -0,0 +1,111 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include +#include "dict-list.h" +#include "memalloc.h" + +/* really __gl_dictListNewDict */ +Dict *dictNewDict( void *frame, + int (*leq)(void *frame, DictKey key1, DictKey key2) ) +{ + Dict *dict = (Dict *) memAlloc( sizeof( Dict )); + DictNode *head; + + if (dict == NULL) return NULL; + + head = &dict->head; + + head->key = NULL; + head->next = head; + head->prev = head; + + dict->frame = frame; + dict->leq = leq; + + return dict; +} + +/* really __gl_dictListDeleteDict */ +void dictDeleteDict( Dict *dict ) +{ + DictNode *node, *next; + + for( node = dict->head.next; node != &dict->head; node = next ) { + next = node->next; + memFree( node ); + } + memFree( dict ); +} + +/* really __gl_dictListInsertBefore */ +DictNode *dictInsertBefore( Dict *dict, DictNode *node, DictKey key ) +{ + DictNode *newNode; + + do { + node = node->prev; + } while( node->key != NULL && ! (*dict->leq)(dict->frame, node->key, key)); + + newNode = (DictNode *) memAlloc( sizeof( DictNode )); + if (newNode == NULL) return NULL; + + newNode->key = key; + newNode->next = node->next; + node->next->prev = newNode; + newNode->prev = node; + node->next = newNode; + + return newNode; +} + +/* really __gl_dictListDelete */ +void dictDelete( Dict *dict, DictNode *node ) /*ARGSUSED*/ +{ + node->next->prev = node->prev; + node->prev->next = node->next; + memFree( node ); +} + +/* really __gl_dictListSearch */ +DictNode *dictSearch( Dict *dict, DictKey key ) +{ + DictNode *node = &dict->head; + + do { + node = node->next; + } while( node->key != NULL && ! (*dict->leq)(dict->frame, key, node->key)); + + return node; +} diff --git a/GLU/dict.h b/GLU/dict.h new file mode 100644 index 0000000..11331a7 --- /dev/null +++ b/GLU/dict.h @@ -0,0 +1,100 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __dict_list_h_ +#define __dict_list_h_ + +/* Use #define's so that another heap implementation can use this one */ + +#define DictKey DictListKey +#define Dict DictList +#define DictNode DictListNode + +#define dictNewDict(frame,leq) __gl_dictListNewDict(frame,leq) +#define dictDeleteDict(dict) __gl_dictListDeleteDict(dict) + +#define dictSearch(dict,key) __gl_dictListSearch(dict,key) +#define dictInsert(dict,key) __gl_dictListInsert(dict,key) +#define dictInsertBefore(dict,node,key) __gl_dictListInsertBefore(dict,node,key) +#define dictDelete(dict,node) __gl_dictListDelete(dict,node) + +#define dictKey(n) __gl_dictListKey(n) +#define dictSucc(n) __gl_dictListSucc(n) +#define dictPred(n) __gl_dictListPred(n) +#define dictMin(d) __gl_dictListMin(d) +#define dictMax(d) __gl_dictListMax(d) + + + +typedef void *DictKey; +typedef struct Dict Dict; +typedef struct DictNode DictNode; + +Dict *dictNewDict( + void *frame, + int (*leq)(void *frame, DictKey key1, DictKey key2) ); + +void dictDeleteDict( Dict *dict ); + +/* Search returns the node with the smallest key greater than or equal + * to the given key. If there is no such key, returns a node whose + * key is NULL. Similarly, Succ(Max(d)) has a NULL key, etc. + */ +DictNode *dictSearch( Dict *dict, DictKey key ); +DictNode *dictInsertBefore( Dict *dict, DictNode *node, DictKey key ); +void dictDelete( Dict *dict, DictNode *node ); + +#define __gl_dictListKey(n) ((n)->key) +#define __gl_dictListSucc(n) ((n)->next) +#define __gl_dictListPred(n) ((n)->prev) +#define __gl_dictListMin(d) ((d)->head.next) +#define __gl_dictListMax(d) ((d)->head.prev) +#define __gl_dictListInsert(d,k) (dictInsertBefore((d),&(d)->head,(k))) + + +/*** Private data structures ***/ + +struct DictNode { + DictKey key; + DictNode *next; + DictNode *prev; +}; + +struct Dict { + DictNode head; + void *frame; + int (*leq)(void *frame, DictKey key1, DictKey key2); +}; + +#endif diff --git a/GLU/geom.c b/GLU/geom.c new file mode 100644 index 0000000..7d3b8d8 --- /dev/null +++ b/GLU/geom.c @@ -0,0 +1,264 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include "mesh.h" +#include "geom.h" + +int __gl_vertLeq( GLUvertex *u, GLUvertex *v ) +{ + /* Returns TRUE if u is lexicographically <= v. */ + + return VertLeq( u, v ); +} + +GLdouble __gl_edgeEval( GLUvertex *u, GLUvertex *v, GLUvertex *w ) +{ + /* Given three vertices u,v,w such that VertLeq(u,v) && VertLeq(v,w), + * evaluates the t-coord of the edge uw at the s-coord of the vertex v. + * Returns v->t - (uw)(v->s), ie. the signed distance from uw to v. + * If uw is vertical (and thus passes thru v), the result is zero. + * + * The calculation is extremely accurate and stable, even when v + * is very close to u or w. In particular if we set v->t = 0 and + * let r be the negated result (this evaluates (uw)(v->s)), then + * r is guaranteed to satisfy MIN(u->t,w->t) <= r <= MAX(u->t,w->t). + */ + GLdouble gapL, gapR; + + assert( VertLeq( u, v ) && VertLeq( v, w )); + + gapL = v->s - u->s; + gapR = w->s - v->s; + + if( gapL + gapR > 0 ) { + if( gapL < gapR ) { + return (v->t - u->t) + (u->t - w->t) * (gapL / (gapL + gapR)); + } else { + return (v->t - w->t) + (w->t - u->t) * (gapR / (gapL + gapR)); + } + } + /* vertical line */ + return 0; +} + +GLdouble __gl_edgeSign( GLUvertex *u, GLUvertex *v, GLUvertex *w ) +{ + /* Returns a number whose sign matches EdgeEval(u,v,w) but which + * is cheaper to evaluate. Returns > 0, == 0 , or < 0 + * as v is above, on, or below the edge uw. + */ + GLdouble gapL, gapR; + + assert( VertLeq( u, v ) && VertLeq( v, w )); + + gapL = v->s - u->s; + gapR = w->s - v->s; + + if( gapL + gapR > 0 ) { + return (v->t - w->t) * gapL + (v->t - u->t) * gapR; + } + /* vertical line */ + return 0; +} + + +/*********************************************************************** + * Define versions of EdgeSign, EdgeEval with s and t transposed. + */ + +GLdouble __gl_transEval( GLUvertex *u, GLUvertex *v, GLUvertex *w ) +{ + /* Given three vertices u,v,w such that TransLeq(u,v) && TransLeq(v,w), + * evaluates the t-coord of the edge uw at the s-coord of the vertex v. + * Returns v->s - (uw)(v->t), ie. the signed distance from uw to v. + * If uw is vertical (and thus passes thru v), the result is zero. + * + * The calculation is extremely accurate and stable, even when v + * is very close to u or w. In particular if we set v->s = 0 and + * let r be the negated result (this evaluates (uw)(v->t)), then + * r is guaranteed to satisfy MIN(u->s,w->s) <= r <= MAX(u->s,w->s). + */ + GLdouble gapL, gapR; + + assert( TransLeq( u, v ) && TransLeq( v, w )); + + gapL = v->t - u->t; + gapR = w->t - v->t; + + if( gapL + gapR > 0 ) { + if( gapL < gapR ) { + return (v->s - u->s) + (u->s - w->s) * (gapL / (gapL + gapR)); + } else { + return (v->s - w->s) + (w->s - u->s) * (gapR / (gapL + gapR)); + } + } + /* vertical line */ + return 0; +} + +GLdouble __gl_transSign( GLUvertex *u, GLUvertex *v, GLUvertex *w ) +{ + /* Returns a number whose sign matches TransEval(u,v,w) but which + * is cheaper to evaluate. Returns > 0, == 0 , or < 0 + * as v is above, on, or below the edge uw. + */ + GLdouble gapL, gapR; + + assert( TransLeq( u, v ) && TransLeq( v, w )); + + gapL = v->t - u->t; + gapR = w->t - v->t; + + if( gapL + gapR > 0 ) { + return (v->s - w->s) * gapL + (v->s - u->s) * gapR; + } + /* vertical line */ + return 0; +} + + +int __gl_vertCCW( GLUvertex *u, GLUvertex *v, GLUvertex *w ) +{ + /* For almost-degenerate situations, the results are not reliable. + * Unless the floating-point arithmetic can be performed without + * rounding errors, *any* implementation will give incorrect results + * on some degenerate inputs, so the client must have some way to + * handle this situation. + */ + return (u->s*(v->t - w->t) + v->s*(w->t - u->t) + w->s*(u->t - v->t)) >= 0; +} + +/* Given parameters a,x,b,y returns the value (b*x+a*y)/(a+b), + * or (x+y)/2 if a==b==0. It requires that a,b >= 0, and enforces + * this in the rare case that one argument is slightly negative. + * The implementation is extremely stable numerically. + * In particular it guarantees that the result r satisfies + * MIN(x,y) <= r <= MAX(x,y), and the results are very accurate + * even when a and b differ greatly in magnitude. + */ +#define RealInterpolate(a,x,b,y) \ + (a = (a < 0) ? 0 : a, b = (b < 0) ? 0 : b, \ + ((a <= b) ? ((b == 0) ? ((x+y) / 2) \ + : (x + (y-x) * (a/(a+b)))) \ + : (y + (x-y) * (b/(a+b))))) + +#ifndef FOR_TRITE_TEST_PROGRAM +#define Interpolate(a,x,b,y) RealInterpolate(a,x,b,y) +#else + +/* Claim: the ONLY property the sweep algorithm relies on is that + * MIN(x,y) <= r <= MAX(x,y). This is a nasty way to test that. + */ +#include +extern int RandomInterpolate; + +GLdouble Interpolate( GLdouble a, GLdouble x, GLdouble b, GLdouble y) +{ +printf("*********************%d\n",RandomInterpolate); + if( RandomInterpolate ) { + a = 1.2 * drand48() - 0.1; + a = (a < 0) ? 0 : ((a > 1) ? 1 : a); + b = 1.0 - a; + } + return RealInterpolate(a,x,b,y); +} + +#endif + +#define Swap(a,b) if (1) { GLUvertex *t = a; a = b; b = t; } else + +void __gl_edgeIntersect( GLUvertex *o1, GLUvertex *d1, + GLUvertex *o2, GLUvertex *d2, + GLUvertex *v ) +/* Given edges (o1,d1) and (o2,d2), compute their point of intersection. + * The computed point is guaranteed to lie in the intersection of the + * bounding rectangles defined by each edge. + */ +{ + GLdouble z1, z2; + + /* This is certainly not the most efficient way to find the intersection + * of two line segments, but it is very numerically stable. + * + * Strategy: find the two middle vertices in the VertLeq ordering, + * and interpolate the intersection s-value from these. Then repeat + * using the TransLeq ordering to find the intersection t-value. + */ + + if( ! VertLeq( o1, d1 )) { Swap( o1, d1 ); } + if( ! VertLeq( o2, d2 )) { Swap( o2, d2 ); } + if( ! VertLeq( o1, o2 )) { Swap( o1, o2 ); Swap( d1, d2 ); } + + if( ! VertLeq( o2, d1 )) { + /* Technically, no intersection -- do our best */ + v->s = (o2->s + d1->s) / 2; + } else if( VertLeq( d1, d2 )) { + /* Interpolate between o2 and d1 */ + z1 = EdgeEval( o1, o2, d1 ); + z2 = EdgeEval( o2, d1, d2 ); + if( z1+z2 < 0 ) { z1 = -z1; z2 = -z2; } + v->s = Interpolate( z1, o2->s, z2, d1->s ); + } else { + /* Interpolate between o2 and d2 */ + z1 = EdgeSign( o1, o2, d1 ); + z2 = -EdgeSign( o1, d2, d1 ); + if( z1+z2 < 0 ) { z1 = -z1; z2 = -z2; } + v->s = Interpolate( z1, o2->s, z2, d2->s ); + } + + /* Now repeat the process for t */ + + if( ! TransLeq( o1, d1 )) { Swap( o1, d1 ); } + if( ! TransLeq( o2, d2 )) { Swap( o2, d2 ); } + if( ! TransLeq( o1, o2 )) { Swap( o1, o2 ); Swap( d1, d2 ); } + + if( ! TransLeq( o2, d1 )) { + /* Technically, no intersection -- do our best */ + v->t = (o2->t + d1->t) / 2; + } else if( TransLeq( d1, d2 )) { + /* Interpolate between o2 and d1 */ + z1 = TransEval( o1, o2, d1 ); + z2 = TransEval( o2, d1, d2 ); + if( z1+z2 < 0 ) { z1 = -z1; z2 = -z2; } + v->t = Interpolate( z1, o2->t, z2, d1->t ); + } else { + /* Interpolate between o2 and d2 */ + z1 = TransSign( o1, o2, d1 ); + z2 = -TransSign( o1, d2, d1 ); + if( z1+z2 < 0 ) { z1 = -z1; z2 = -z2; } + v->t = Interpolate( z1, o2->t, z2, d2->t ); + } +} diff --git a/GLU/geom.h b/GLU/geom.h new file mode 100644 index 0000000..5cb76c7 --- /dev/null +++ b/GLU/geom.h @@ -0,0 +1,84 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __geom_h_ +#define __geom_h_ + +#include "mesh.h" + +#ifdef NO_BRANCH_CONDITIONS +/* MIPS architecture has special instructions to evaluate boolean + * conditions -- more efficient than branching, IF you can get the + * compiler to generate the right instructions (SGI compiler doesn't) + */ +#define VertEq(u,v) (((u)->s == (v)->s) & ((u)->t == (v)->t)) +#define VertLeq(u,v) (((u)->s < (v)->s) | \ + ((u)->s == (v)->s & (u)->t <= (v)->t)) +#else +#define VertEq(u,v) ((u)->s == (v)->s && (u)->t == (v)->t) +#define VertLeq(u,v) (((u)->s < (v)->s) || \ + ((u)->s == (v)->s && (u)->t <= (v)->t)) +#endif + +#define EdgeEval(u,v,w) __gl_edgeEval(u,v,w) +#define EdgeSign(u,v,w) __gl_edgeSign(u,v,w) + +/* Versions of VertLeq, EdgeSign, EdgeEval with s and t transposed. */ + +#define TransLeq(u,v) (((u)->t < (v)->t) || \ + ((u)->t == (v)->t && (u)->s <= (v)->s)) +#define TransEval(u,v,w) __gl_transEval(u,v,w) +#define TransSign(u,v,w) __gl_transSign(u,v,w) + + +#define EdgeGoesLeft(e) VertLeq( (e)->Dst, (e)->Org ) +#define EdgeGoesRight(e) VertLeq( (e)->Org, (e)->Dst ) + +#undef ABS +#define ABS(x) ((x) < 0 ? -(x) : (x)) +#define VertL1dist(u,v) (ABS(u->s - v->s) + ABS(u->t - v->t)) + +#define VertCCW(u,v,w) __gl_vertCCW(u,v,w) + +int __gl_vertLeq( GLUvertex *u, GLUvertex *v ); +GLdouble __gl_edgeEval( GLUvertex *u, GLUvertex *v, GLUvertex *w ); +GLdouble __gl_edgeSign( GLUvertex *u, GLUvertex *v, GLUvertex *w ); +GLdouble __gl_transEval( GLUvertex *u, GLUvertex *v, GLUvertex *w ); +GLdouble __gl_transSign( GLUvertex *u, GLUvertex *v, GLUvertex *w ); +int __gl_vertCCW( GLUvertex *u, GLUvertex *v, GLUvertex *w ); +void __gl_edgeIntersect( GLUvertex *o1, GLUvertex *d1, + GLUvertex *o2, GLUvertex *d2, + GLUvertex *v ); + +#endif diff --git a/GLU/gluos.h b/GLU/gluos.h new file mode 100644 index 0000000..8eaa7a1 --- /dev/null +++ b/GLU/gluos.h @@ -0,0 +1,72 @@ +/* +** gluos.h - operating system dependencies for GLU +** +*/ +#ifdef __VMS +#ifdef __cplusplus +#pragma message disable nocordel +#pragma message disable codeunreachable +#pragma message disable codcauunr +#endif +#endif + +#ifdef __WATCOMC__ +/* Disable *lots* of warnings to get a clean build. I can't be bothered fixing the + * code at the moment, as it is pretty ugly. + */ +#pragma warning 7 10 +#pragma warning 13 10 +#pragma warning 14 10 +#pragma warning 367 10 +#pragma warning 379 10 +#pragma warning 726 10 +#pragma warning 836 10 +#endif + +#ifdef BUILD_FOR_SNAP + +#include +#include +#include + +#elif defined(_WIN32) + +#include /* For _MAX_PATH definition */ +#include +#include + +#define WIN32_LEAN_AND_MEAN +#define NOGDI +#define NOIME +#define NOMINMAX + +#define _WIN32_WINNT 0x0400 +#ifndef STRICT + #define STRICT 1 +#endif + +#include + +/* Disable warnings */ +#pragma warning(disable : 4101) +#pragma warning(disable : 4244) +#pragma warning(disable : 4761) + +#if defined(_MSC_VER) && _MSC_VER >= 1200 && _MSC_VER < 1300 +#pragma comment(linker, "/OPT:NOWIN98") +#endif + +#elif defined(__OS2__) + +#include +#include +#include +#define WINGDIAPI + +#else + +/* Disable Microsoft-specific keywords */ +#define GLAPIENTRY +#define WINGDIAPI + +#endif diff --git a/GLU/memalloc.c b/GLU/memalloc.c new file mode 100644 index 0000000..81879ef --- /dev/null +++ b/GLU/memalloc.c @@ -0,0 +1,55 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "memalloc.h" +#include "string.h" + +int __gl_memInit( size_t maxFast ) +{ +#ifndef NO_MALLOPT +/* mallopt( M_MXFAST, maxFast );*/ +#ifdef MEMORY_DEBUG + mallopt( M_DEBUG, 1 ); +#endif +#endif + return 1; +} + +#ifdef MEMORY_DEBUG +void *__gl_memAlloc( size_t n ) +{ + return memset( malloc( n ), 0xa5, n ); +} +#endif + diff --git a/GLU/memalloc.h b/GLU/memalloc.h new file mode 100644 index 0000000..c2f969b --- /dev/null +++ b/GLU/memalloc.h @@ -0,0 +1,54 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __memalloc_simple_h_ +#define __memalloc_simple_h_ + +#include + +#define memRealloc realloc +#define memFree free + +#define memInit __gl_memInit +/*extern void __gl_memInit( size_t );*/ +extern int __gl_memInit( size_t ); + +#ifndef MEMORY_DEBUG +#define memAlloc malloc +#else +#define memAlloc __gl_memAlloc +extern void * __gl_memAlloc( size_t ); +#endif + +#endif diff --git a/GLU/mesh.c b/GLU/mesh.c new file mode 100644 index 0000000..ae861f8 --- /dev/null +++ b/GLU/mesh.c @@ -0,0 +1,789 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include +#include "mesh.h" +#include "memalloc.h" + +#define TRUE 1 +#define FALSE 0 + +static GLUvertex *allocVertex() +{ + return (GLUvertex *)memAlloc( sizeof( GLUvertex )); +} + +static GLUface *allocFace() +{ + return (GLUface *)memAlloc( sizeof( GLUface )); +} + +/************************ Utility Routines ************************/ + +/* Allocate and free half-edges in pairs for efficiency. + * The *only* place that should use this fact is allocation/free. + */ +typedef struct { GLUhalfEdge e, eSym; } EdgePair; + +/* MakeEdge creates a new pair of half-edges which form their own loop. + * No vertex or face structures are allocated, but these must be assigned + * before the current edge operation is completed. + */ +static GLUhalfEdge *MakeEdge( GLUhalfEdge *eNext ) +{ + GLUhalfEdge *e; + GLUhalfEdge *eSym; + GLUhalfEdge *ePrev; + EdgePair *pair = (EdgePair *)memAlloc( sizeof( EdgePair )); + if (pair == NULL) return NULL; + + e = &pair->e; + eSym = &pair->eSym; + + /* Make sure eNext points to the first edge of the edge pair */ + if( eNext->Sym < eNext ) { eNext = eNext->Sym; } + + /* Insert in circular doubly-linked list before eNext. + * Note that the prev pointer is stored in Sym->next. + */ + ePrev = eNext->Sym->next; + eSym->next = ePrev; + ePrev->Sym->next = e; + e->next = eNext; + eNext->Sym->next = eSym; + + e->Sym = eSym; + e->Onext = e; + e->Lnext = eSym; + e->Org = NULL; + e->Lface = NULL; + e->winding = 0; + e->activeRegion = NULL; + + eSym->Sym = e; + eSym->Onext = eSym; + eSym->Lnext = e; + eSym->Org = NULL; + eSym->Lface = NULL; + eSym->winding = 0; + eSym->activeRegion = NULL; + + return e; +} + +/* Splice( a, b ) is best described by the Guibas/Stolfi paper or the + * CS348a notes (see mesh.h). Basically it modifies the mesh so that + * a->Onext and b->Onext are exchanged. This can have various effects + * depending on whether a and b belong to different face or vertex rings. + * For more explanation see __gl_meshSplice() below. + */ +static void Splice( GLUhalfEdge *a, GLUhalfEdge *b ) +{ + GLUhalfEdge *aOnext = a->Onext; + GLUhalfEdge *bOnext = b->Onext; + + aOnext->Sym->Lnext = b; + bOnext->Sym->Lnext = a; + a->Onext = bOnext; + b->Onext = aOnext; +} + +/* MakeVertex( newVertex, eOrig, vNext ) attaches a new vertex and makes it the + * origin of all edges in the vertex loop to which eOrig belongs. "vNext" gives + * a place to insert the new vertex in the global vertex list. We insert + * the new vertex *before* vNext so that algorithms which walk the vertex + * list will not see the newly created vertices. + */ +static void MakeVertex( GLUvertex *newVertex, + GLUhalfEdge *eOrig, GLUvertex *vNext ) +{ + GLUhalfEdge *e; + GLUvertex *vPrev; + GLUvertex *vNew = newVertex; + + assert(vNew != NULL); + + /* insert in circular doubly-linked list before vNext */ + vPrev = vNext->prev; + vNew->prev = vPrev; + vPrev->next = vNew; + vNew->next = vNext; + vNext->prev = vNew; + + vNew->anEdge = eOrig; + vNew->data = NULL; + /* leave coords, s, t undefined */ + + /* fix other edges on this vertex loop */ + e = eOrig; + do { + e->Org = vNew; + e = e->Onext; + } while( e != eOrig ); +} + +/* MakeFace( newFace, eOrig, fNext ) attaches a new face and makes it the left + * face of all edges in the face loop to which eOrig belongs. "fNext" gives + * a place to insert the new face in the global face list. We insert + * the new face *before* fNext so that algorithms which walk the face + * list will not see the newly created faces. + */ +static void MakeFace( GLUface *newFace, GLUhalfEdge *eOrig, GLUface *fNext ) +{ + GLUhalfEdge *e; + GLUface *fPrev; + GLUface *fNew = newFace; + + assert(fNew != NULL); + + /* insert in circular doubly-linked list before fNext */ + fPrev = fNext->prev; + fNew->prev = fPrev; + fPrev->next = fNew; + fNew->next = fNext; + fNext->prev = fNew; + + fNew->anEdge = eOrig; + fNew->data = NULL; + fNew->trail = NULL; + fNew->marked = FALSE; + + /* The new face is marked "inside" if the old one was. This is a + * convenience for the common case where a face has been split in two. + */ + fNew->inside = fNext->inside; + + /* fix other edges on this face loop */ + e = eOrig; + do { + e->Lface = fNew; + e = e->Lnext; + } while( e != eOrig ); +} + +/* KillEdge( eDel ) destroys an edge (the half-edges eDel and eDel->Sym), + * and removes from the global edge list. + */ +static void KillEdge( GLUhalfEdge *eDel ) +{ + GLUhalfEdge *ePrev, *eNext; + + /* Half-edges are allocated in pairs, see EdgePair above */ + if( eDel->Sym < eDel ) { eDel = eDel->Sym; } + + /* delete from circular doubly-linked list */ + eNext = eDel->next; + ePrev = eDel->Sym->next; + eNext->Sym->next = ePrev; + ePrev->Sym->next = eNext; + + memFree( eDel ); +} + + +/* KillVertex( vDel ) destroys a vertex and removes it from the global + * vertex list. It updates the vertex loop to point to a given new vertex. + */ +static void KillVertex( GLUvertex *vDel, GLUvertex *newOrg ) +{ + GLUhalfEdge *e, *eStart = vDel->anEdge; + GLUvertex *vPrev, *vNext; + + /* change the origin of all affected edges */ + e = eStart; + do { + e->Org = newOrg; + e = e->Onext; + } while( e != eStart ); + + /* delete from circular doubly-linked list */ + vPrev = vDel->prev; + vNext = vDel->next; + vNext->prev = vPrev; + vPrev->next = vNext; + + memFree( vDel ); +} + +/* KillFace( fDel ) destroys a face and removes it from the global face + * list. It updates the face loop to point to a given new face. + */ +static void KillFace( GLUface *fDel, GLUface *newLface ) +{ + GLUhalfEdge *e, *eStart = fDel->anEdge; + GLUface *fPrev, *fNext; + + /* change the left face of all affected edges */ + e = eStart; + do { + e->Lface = newLface; + e = e->Lnext; + } while( e != eStart ); + + /* delete from circular doubly-linked list */ + fPrev = fDel->prev; + fNext = fDel->next; + fNext->prev = fPrev; + fPrev->next = fNext; + + memFree( fDel ); +} + + +/****************** Basic Edge Operations **********************/ + +/* __gl_meshMakeEdge creates one edge, two vertices, and a loop (face). + * The loop consists of the two new half-edges. + */ +GLUhalfEdge *__gl_meshMakeEdge( GLUmesh *mesh ) +{ + GLUvertex *newVertex1= allocVertex(); + GLUvertex *newVertex2= allocVertex(); + GLUface *newFace= allocFace(); + GLUhalfEdge *e; + + /* if any one is null then all get freed */ + if (newVertex1 == NULL || newVertex2 == NULL || newFace == NULL) { + if (newVertex1 != NULL) memFree(newVertex1); + if (newVertex2 != NULL) memFree(newVertex2); + if (newFace != NULL) memFree(newFace); + return NULL; + } + + e = MakeEdge( &mesh->eHead ); + if (e == NULL) return NULL; + + MakeVertex( newVertex1, e, &mesh->vHead ); + MakeVertex( newVertex2, e->Sym, &mesh->vHead ); + MakeFace( newFace, e, &mesh->fHead ); + return e; +} + + +/* __gl_meshSplice( eOrg, eDst ) is the basic operation for changing the + * mesh connectivity and topology. It changes the mesh so that + * eOrg->Onext <- OLD( eDst->Onext ) + * eDst->Onext <- OLD( eOrg->Onext ) + * where OLD(...) means the value before the meshSplice operation. + * + * This can have two effects on the vertex structure: + * - if eOrg->Org != eDst->Org, the two vertices are merged together + * - if eOrg->Org == eDst->Org, the origin is split into two vertices + * In both cases, eDst->Org is changed and eOrg->Org is untouched. + * + * Similarly (and independently) for the face structure, + * - if eOrg->Lface == eDst->Lface, one loop is split into two + * - if eOrg->Lface != eDst->Lface, two distinct loops are joined into one + * In both cases, eDst->Lface is changed and eOrg->Lface is unaffected. + * + * Some special cases: + * If eDst == eOrg, the operation has no effect. + * If eDst == eOrg->Lnext, the new face will have a single edge. + * If eDst == eOrg->Lprev, the old face will have a single edge. + * If eDst == eOrg->Onext, the new vertex will have a single edge. + * If eDst == eOrg->Oprev, the old vertex will have a single edge. + */ +int __gl_meshSplice( GLUhalfEdge *eOrg, GLUhalfEdge *eDst ) +{ + int joiningLoops = FALSE; + int joiningVertices = FALSE; + + if( eOrg == eDst ) return 1; + + if( eDst->Org != eOrg->Org ) { + /* We are merging two disjoint vertices -- destroy eDst->Org */ + joiningVertices = TRUE; + KillVertex( eDst->Org, eOrg->Org ); + } + if( eDst->Lface != eOrg->Lface ) { + /* We are connecting two disjoint loops -- destroy eDst->Lface */ + joiningLoops = TRUE; + KillFace( eDst->Lface, eOrg->Lface ); + } + + /* Change the edge structure */ + Splice( eDst, eOrg ); + + if( ! joiningVertices ) { + GLUvertex *newVertex= allocVertex(); + if (newVertex == NULL) return 0; + + /* We split one vertex into two -- the new vertex is eDst->Org. + * Make sure the old vertex points to a valid half-edge. + */ + MakeVertex( newVertex, eDst, eOrg->Org ); + eOrg->Org->anEdge = eOrg; + } + if( ! joiningLoops ) { + GLUface *newFace= allocFace(); + if (newFace == NULL) return 0; + + /* We split one loop into two -- the new loop is eDst->Lface. + * Make sure the old face points to a valid half-edge. + */ + MakeFace( newFace, eDst, eOrg->Lface ); + eOrg->Lface->anEdge = eOrg; + } + + return 1; +} + + +/* __gl_meshDelete( eDel ) removes the edge eDel. There are several cases: + * if (eDel->Lface != eDel->Rface), we join two loops into one; the loop + * eDel->Lface is deleted. Otherwise, we are splitting one loop into two; + * the newly created loop will contain eDel->Dst. If the deletion of eDel + * would create isolated vertices, those are deleted as well. + * + * This function could be implemented as two calls to __gl_meshSplice + * plus a few calls to memFree, but this would allocate and delete + * unnecessary vertices and faces. + */ +int __gl_meshDelete( GLUhalfEdge *eDel ) +{ + GLUhalfEdge *eDelSym = eDel->Sym; + int joiningLoops = FALSE; + + /* First step: disconnect the origin vertex eDel->Org. We make all + * changes to get a consistent mesh in this "intermediate" state. + */ + if( eDel->Lface != eDel->Rface ) { + /* We are joining two loops into one -- remove the left face */ + joiningLoops = TRUE; + KillFace( eDel->Lface, eDel->Rface ); + } + + if( eDel->Onext == eDel ) { + KillVertex( eDel->Org, NULL ); + } else { + /* Make sure that eDel->Org and eDel->Rface point to valid half-edges */ + eDel->Rface->anEdge = eDel->Oprev; + eDel->Org->anEdge = eDel->Onext; + + Splice( eDel, eDel->Oprev ); + if( ! joiningLoops ) { + GLUface *newFace= allocFace(); + if (newFace == NULL) return 0; + + /* We are splitting one loop into two -- create a new loop for eDel. */ + MakeFace( newFace, eDel, eDel->Lface ); + } + } + + /* Claim: the mesh is now in a consistent state, except that eDel->Org + * may have been deleted. Now we disconnect eDel->Dst. + */ + if( eDelSym->Onext == eDelSym ) { + KillVertex( eDelSym->Org, NULL ); + KillFace( eDelSym->Lface, NULL ); + } else { + /* Make sure that eDel->Dst and eDel->Lface point to valid half-edges */ + eDel->Lface->anEdge = eDelSym->Oprev; + eDelSym->Org->anEdge = eDelSym->Onext; + Splice( eDelSym, eDelSym->Oprev ); + } + + /* Any isolated vertices or faces have already been freed. */ + KillEdge( eDel ); + + return 1; +} + + +/******************** Other Edge Operations **********************/ + +/* All these routines can be implemented with the basic edge + * operations above. They are provided for convenience and efficiency. + */ + + +/* __gl_meshAddEdgeVertex( eOrg ) creates a new edge eNew such that + * eNew == eOrg->Lnext, and eNew->Dst is a newly created vertex. + * eOrg and eNew will have the same left face. + */ +GLUhalfEdge *__gl_meshAddEdgeVertex( GLUhalfEdge *eOrg ) +{ + GLUhalfEdge *eNewSym; + GLUhalfEdge *eNew = MakeEdge( eOrg ); + if (eNew == NULL) return NULL; + + eNewSym = eNew->Sym; + + /* Connect the new edge appropriately */ + Splice( eNew, eOrg->Lnext ); + + /* Set the vertex and face information */ + eNew->Org = eOrg->Dst; + { + GLUvertex *newVertex= allocVertex(); + if (newVertex == NULL) return NULL; + + MakeVertex( newVertex, eNewSym, eNew->Org ); + } + eNew->Lface = eNewSym->Lface = eOrg->Lface; + + return eNew; +} + + +/* __gl_meshSplitEdge( eOrg ) splits eOrg into two edges eOrg and eNew, + * such that eNew == eOrg->Lnext. The new vertex is eOrg->Dst == eNew->Org. + * eOrg and eNew will have the same left face. + */ +GLUhalfEdge *__gl_meshSplitEdge( GLUhalfEdge *eOrg ) +{ + GLUhalfEdge *eNew; + GLUhalfEdge *tempHalfEdge= __gl_meshAddEdgeVertex( eOrg ); + if (tempHalfEdge == NULL) return NULL; + + eNew = tempHalfEdge->Sym; + + /* Disconnect eOrg from eOrg->Dst and connect it to eNew->Org */ + Splice( eOrg->Sym, eOrg->Sym->Oprev ); + Splice( eOrg->Sym, eNew ); + + /* Set the vertex and face information */ + eOrg->Dst = eNew->Org; + eNew->Dst->anEdge = eNew->Sym; /* may have pointed to eOrg->Sym */ + eNew->Rface = eOrg->Rface; + eNew->winding = eOrg->winding; /* copy old winding information */ + eNew->Sym->winding = eOrg->Sym->winding; + + return eNew; +} + + +/* __gl_meshConnect( eOrg, eDst ) creates a new edge from eOrg->Dst + * to eDst->Org, and returns the corresponding half-edge eNew. + * If eOrg->Lface == eDst->Lface, this splits one loop into two, + * and the newly created loop is eNew->Lface. Otherwise, two disjoint + * loops are merged into one, and the loop eDst->Lface is destroyed. + * + * If (eOrg == eDst), the new face will have only two edges. + * If (eOrg->Lnext == eDst), the old face is reduced to a single edge. + * If (eOrg->Lnext->Lnext == eDst), the old face is reduced to two edges. + */ +GLUhalfEdge *__gl_meshConnect( GLUhalfEdge *eOrg, GLUhalfEdge *eDst ) +{ + GLUhalfEdge *eNewSym; + int joiningLoops = FALSE; + GLUhalfEdge *eNew = MakeEdge( eOrg ); + if (eNew == NULL) return NULL; + + eNewSym = eNew->Sym; + + if( eDst->Lface != eOrg->Lface ) { + /* We are connecting two disjoint loops -- destroy eDst->Lface */ + joiningLoops = TRUE; + KillFace( eDst->Lface, eOrg->Lface ); + } + + /* Connect the new edge appropriately */ + Splice( eNew, eOrg->Lnext ); + Splice( eNewSym, eDst ); + + /* Set the vertex and face information */ + eNew->Org = eOrg->Dst; + eNewSym->Org = eDst->Org; + eNew->Lface = eNewSym->Lface = eOrg->Lface; + + /* Make sure the old face points to a valid half-edge */ + eOrg->Lface->anEdge = eNewSym; + + if( ! joiningLoops ) { + GLUface *newFace= allocFace(); + if (newFace == NULL) return NULL; + + /* We split one loop into two -- the new loop is eNew->Lface */ + MakeFace( newFace, eNew, eOrg->Lface ); + } + return eNew; +} + + +/******************** Other Operations **********************/ + +/* __gl_meshZapFace( fZap ) destroys a face and removes it from the + * global face list. All edges of fZap will have a NULL pointer as their + * left face. Any edges which also have a NULL pointer as their right face + * are deleted entirely (along with any isolated vertices this produces). + * An entire mesh can be deleted by zapping its faces, one at a time, + * in any order. Zapped faces cannot be used in further mesh operations! + */ +void __gl_meshZapFace( GLUface *fZap ) +{ + GLUhalfEdge *eStart = fZap->anEdge; + GLUhalfEdge *e, *eNext, *eSym; + GLUface *fPrev, *fNext; + + /* walk around face, deleting edges whose right face is also NULL */ + eNext = eStart->Lnext; + do { + e = eNext; + eNext = e->Lnext; + + e->Lface = NULL; + if( e->Rface == NULL ) { + /* delete the edge -- see __gl_MeshDelete above */ + + if( e->Onext == e ) { + KillVertex( e->Org, NULL ); + } else { + /* Make sure that e->Org points to a valid half-edge */ + e->Org->anEdge = e->Onext; + Splice( e, e->Oprev ); + } + eSym = e->Sym; + if( eSym->Onext == eSym ) { + KillVertex( eSym->Org, NULL ); + } else { + /* Make sure that eSym->Org points to a valid half-edge */ + eSym->Org->anEdge = eSym->Onext; + Splice( eSym, eSym->Oprev ); + } + KillEdge( e ); + } + } while( e != eStart ); + + /* delete from circular doubly-linked list */ + fPrev = fZap->prev; + fNext = fZap->next; + fNext->prev = fPrev; + fPrev->next = fNext; + + memFree( fZap ); +} + + +/* __gl_meshNewMesh() creates a new mesh with no edges, no vertices, + * and no loops (what we usually call a "face"). + */ +GLUmesh *__gl_meshNewMesh( void ) +{ + GLUvertex *v; + GLUface *f; + GLUhalfEdge *e; + GLUhalfEdge *eSym; + GLUmesh *mesh = (GLUmesh *)memAlloc( sizeof( GLUmesh )); + if (mesh == NULL) { + return NULL; + } + + v = &mesh->vHead; + f = &mesh->fHead; + e = &mesh->eHead; + eSym = &mesh->eHeadSym; + + v->next = v->prev = v; + v->anEdge = NULL; + v->data = NULL; + + f->next = f->prev = f; + f->anEdge = NULL; + f->data = NULL; + f->trail = NULL; + f->marked = FALSE; + f->inside = FALSE; + + e->next = e; + e->Sym = eSym; + e->Onext = NULL; + e->Lnext = NULL; + e->Org = NULL; + e->Lface = NULL; + e->winding = 0; + e->activeRegion = NULL; + + eSym->next = eSym; + eSym->Sym = e; + eSym->Onext = NULL; + eSym->Lnext = NULL; + eSym->Org = NULL; + eSym->Lface = NULL; + eSym->winding = 0; + eSym->activeRegion = NULL; + + return mesh; +} + + +/* __gl_meshUnion( mesh1, mesh2 ) forms the union of all structures in + * both meshes, and returns the new mesh (the old meshes are destroyed). + */ +GLUmesh *__gl_meshUnion( GLUmesh *mesh1, GLUmesh *mesh2 ) +{ + GLUface *f1 = &mesh1->fHead; + GLUvertex *v1 = &mesh1->vHead; + GLUhalfEdge *e1 = &mesh1->eHead; + GLUface *f2 = &mesh2->fHead; + GLUvertex *v2 = &mesh2->vHead; + GLUhalfEdge *e2 = &mesh2->eHead; + + /* Add the faces, vertices, and edges of mesh2 to those of mesh1 */ + if( f2->next != f2 ) { + f1->prev->next = f2->next; + f2->next->prev = f1->prev; + f2->prev->next = f1; + f1->prev = f2->prev; + } + + if( v2->next != v2 ) { + v1->prev->next = v2->next; + v2->next->prev = v1->prev; + v2->prev->next = v1; + v1->prev = v2->prev; + } + + if( e2->next != e2 ) { + e1->Sym->next->Sym->next = e2->next; + e2->next->Sym->next = e1->Sym->next; + e2->Sym->next->Sym->next = e1; + e1->Sym->next = e2->Sym->next; + } + + memFree( mesh2 ); + return mesh1; +} + + +#ifdef DELETE_BY_ZAPPING + +/* __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh. + */ +void __gl_meshDeleteMesh( GLUmesh *mesh ) +{ + GLUface *fHead = &mesh->fHead; + + while( fHead->next != fHead ) { + __gl_meshZapFace( fHead->next ); + } + assert( mesh->vHead.next == &mesh->vHead ); + + memFree( mesh ); +} + +#else + +/* __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh. + */ +void __gl_meshDeleteMesh( GLUmesh *mesh ) +{ + GLUface *f, *fNext; + GLUvertex *v, *vNext; + GLUhalfEdge *e, *eNext; + + for( f = mesh->fHead.next; f != &mesh->fHead; f = fNext ) { + fNext = f->next; + memFree( f ); + } + + for( v = mesh->vHead.next; v != &mesh->vHead; v = vNext ) { + vNext = v->next; + memFree( v ); + } + + for( e = mesh->eHead.next; e != &mesh->eHead; e = eNext ) { + /* One call frees both e and e->Sym (see EdgePair above) */ + eNext = e->next; + memFree( e ); + } + + memFree( mesh ); +} + +#endif + +#ifndef NDEBUG + +/* __gl_meshCheckMesh( mesh ) checks a mesh for self-consistency. + */ +void __gl_meshCheckMesh( GLUmesh *mesh ) +{ + GLUface *fHead = &mesh->fHead; + GLUvertex *vHead = &mesh->vHead; + GLUhalfEdge *eHead = &mesh->eHead; + GLUface *f, *fPrev; + GLUvertex *v, *vPrev; + GLUhalfEdge *e, *ePrev; + + fPrev = fHead; + for( fPrev = fHead ; (f = fPrev->next) != fHead; fPrev = f) { + assert( f->prev == fPrev ); + e = f->anEdge; + do { + assert( e->Sym != e ); + assert( e->Sym->Sym == e ); + assert( e->Lnext->Onext->Sym == e ); + assert( e->Onext->Sym->Lnext == e ); + assert( e->Lface == f ); + e = e->Lnext; + } while( e != f->anEdge ); + } + assert( f->prev == fPrev && f->anEdge == NULL && f->data == NULL ); + + vPrev = vHead; + for( vPrev = vHead ; (v = vPrev->next) != vHead; vPrev = v) { + assert( v->prev == vPrev ); + e = v->anEdge; + do { + assert( e->Sym != e ); + assert( e->Sym->Sym == e ); + assert( e->Lnext->Onext->Sym == e ); + assert( e->Onext->Sym->Lnext == e ); + assert( e->Org == v ); + e = e->Onext; + } while( e != v->anEdge ); + } + assert( v->prev == vPrev && v->anEdge == NULL && v->data == NULL ); + + ePrev = eHead; + for( ePrev = eHead ; (e = ePrev->next) != eHead; ePrev = e) { + assert( e->Sym->next == ePrev->Sym ); + assert( e->Sym != e ); + assert( e->Sym->Sym == e ); + assert( e->Org != NULL ); + assert( e->Dst != NULL ); + assert( e->Lnext->Onext->Sym == e ); + assert( e->Onext->Sym->Lnext == e ); + } + assert( e->Sym->next == ePrev->Sym + && e->Sym == &mesh->eHeadSym + && e->Sym->Sym == e + && e->Org == NULL && e->Dst == NULL + && e->Lface == NULL && e->Rface == NULL ); +} + +#endif diff --git a/GLU/mesh.h b/GLU/mesh.h new file mode 100644 index 0000000..690c5f2 --- /dev/null +++ b/GLU/mesh.h @@ -0,0 +1,266 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __mesh_h_ +#define __mesh_h_ + +#include + +typedef struct GLUmesh GLUmesh; + +typedef struct GLUvertex GLUvertex; +typedef struct GLUface GLUface; +typedef struct GLUhalfEdge GLUhalfEdge; + +typedef struct ActiveRegion ActiveRegion; /* Internal data */ + +/* The mesh structure is similar in spirit, notation, and operations + * to the "quad-edge" structure (see L. Guibas and J. Stolfi, Primitives + * for the manipulation of general subdivisions and the computation of + * Voronoi diagrams, ACM Transactions on Graphics, 4(2):74-123, April 1985). + * For a simplified description, see the course notes for CS348a, + * "Mathematical Foundations of Computer Graphics", available at the + * Stanford bookstore (and taught during the fall quarter). + * The implementation also borrows a tiny subset of the graph-based approach + * use in Mantyla's Geometric Work Bench (see M. Mantyla, An Introduction + * to Sold Modeling, Computer Science Press, Rockville, Maryland, 1988). + * + * The fundamental data structure is the "half-edge". Two half-edges + * go together to make an edge, but they point in opposite directions. + * Each half-edge has a pointer to its mate (the "symmetric" half-edge Sym), + * its origin vertex (Org), the face on its left side (Lface), and the + * adjacent half-edges in the CCW direction around the origin vertex + * (Onext) and around the left face (Lnext). There is also a "next" + * pointer for the global edge list (see below). + * + * The notation used for mesh navigation: + * Sym = the mate of a half-edge (same edge, but opposite direction) + * Onext = edge CCW around origin vertex (keep same origin) + * Dnext = edge CCW around destination vertex (keep same dest) + * Lnext = edge CCW around left face (dest becomes new origin) + * Rnext = edge CCW around right face (origin becomes new dest) + * + * "prev" means to substitute CW for CCW in the definitions above. + * + * The mesh keeps global lists of all vertices, faces, and edges, + * stored as doubly-linked circular lists with a dummy header node. + * The mesh stores pointers to these dummy headers (vHead, fHead, eHead). + * + * The circular edge list is special; since half-edges always occur + * in pairs (e and e->Sym), each half-edge stores a pointer in only + * one direction. Starting at eHead and following the e->next pointers + * will visit each *edge* once (ie. e or e->Sym, but not both). + * e->Sym stores a pointer in the opposite direction, thus it is + * always true that e->Sym->next->Sym->next == e. + * + * Each vertex has a pointer to next and previous vertices in the + * circular list, and a pointer to a half-edge with this vertex as + * the origin (NULL if this is the dummy header). There is also a + * field "data" for client data. + * + * Each face has a pointer to the next and previous faces in the + * circular list, and a pointer to a half-edge with this face as + * the left face (NULL if this is the dummy header). There is also + * a field "data" for client data. + * + * Note that what we call a "face" is really a loop; faces may consist + * of more than one loop (ie. not simply connected), but there is no + * record of this in the data structure. The mesh may consist of + * several disconnected regions, so it may not be possible to visit + * the entire mesh by starting at a half-edge and traversing the edge + * structure. + * + * The mesh does NOT support isolated vertices; a vertex is deleted along + * with its last edge. Similarly when two faces are merged, one of the + * faces is deleted (see __gl_meshDelete below). For mesh operations, + * all face (loop) and vertex pointers must not be NULL. However, once + * mesh manipulation is finished, __gl_MeshZapFace can be used to delete + * faces of the mesh, one at a time. All external faces can be "zapped" + * before the mesh is returned to the client; then a NULL face indicates + * a region which is not part of the output polygon. + */ + +struct GLUvertex { + GLUvertex *next; /* next vertex (never NULL) */ + GLUvertex *prev; /* previous vertex (never NULL) */ + GLUhalfEdge *anEdge; /* a half-edge with this origin */ + void *data; /* client's data */ + + /* Internal data (keep hidden) */ + GLdouble coords[3]; /* vertex location in 3D */ + GLdouble s, t; /* projection onto the sweep plane */ + long pqHandle; /* to allow deletion from priority queue */ +}; + +struct GLUface { + GLUface *next; /* next face (never NULL) */ + GLUface *prev; /* previous face (never NULL) */ + GLUhalfEdge *anEdge; /* a half edge with this left face */ + void *data; /* room for client's data */ + + /* Internal data (keep hidden) */ + GLUface *trail; /* "stack" for conversion to strips */ + GLboolean marked; /* flag for conversion to strips */ + GLboolean inside; /* this face is in the polygon interior */ +}; + +struct GLUhalfEdge { + GLUhalfEdge *next; /* doubly-linked list (prev==Sym->next) */ + GLUhalfEdge *Sym; /* same edge, opposite direction */ + GLUhalfEdge *Onext; /* next edge CCW around origin */ + GLUhalfEdge *Lnext; /* next edge CCW around left face */ + GLUvertex *Org; /* origin vertex (Overtex too long) */ + GLUface *Lface; /* left face */ + + /* Internal data (keep hidden) */ + ActiveRegion *activeRegion; /* a region with this upper edge (sweep.c) */ + int winding; /* change in winding number when crossing + from the right face to the left face */ +}; + +#define Rface Sym->Lface +#define Dst Sym->Org + +#define Oprev Sym->Lnext +#define Lprev Onext->Sym +#define Dprev Lnext->Sym +#define Rprev Sym->Onext +#define Dnext Rprev->Sym /* 3 pointers */ +#define Rnext Oprev->Sym /* 3 pointers */ + + +struct GLUmesh { + GLUvertex vHead; /* dummy header for vertex list */ + GLUface fHead; /* dummy header for face list */ + GLUhalfEdge eHead; /* dummy header for edge list */ + GLUhalfEdge eHeadSym; /* and its symmetric counterpart */ +}; + +/* The mesh operations below have three motivations: completeness, + * convenience, and efficiency. The basic mesh operations are MakeEdge, + * Splice, and Delete. All the other edge operations can be implemented + * in terms of these. The other operations are provided for convenience + * and/or efficiency. + * + * When a face is split or a vertex is added, they are inserted into the + * global list *before* the existing vertex or face (ie. e->Org or e->Lface). + * This makes it easier to process all vertices or faces in the global lists + * without worrying about processing the same data twice. As a convenience, + * when a face is split, the "inside" flag is copied from the old face. + * Other internal data (v->data, v->activeRegion, f->data, f->marked, + * f->trail, e->winding) is set to zero. + * + * ********************** Basic Edge Operations ************************** + * + * __gl_meshMakeEdge( mesh ) creates one edge, two vertices, and a loop. + * The loop (face) consists of the two new half-edges. + * + * __gl_meshSplice( eOrg, eDst ) is the basic operation for changing the + * mesh connectivity and topology. It changes the mesh so that + * eOrg->Onext <- OLD( eDst->Onext ) + * eDst->Onext <- OLD( eOrg->Onext ) + * where OLD(...) means the value before the meshSplice operation. + * + * This can have two effects on the vertex structure: + * - if eOrg->Org != eDst->Org, the two vertices are merged together + * - if eOrg->Org == eDst->Org, the origin is split into two vertices + * In both cases, eDst->Org is changed and eOrg->Org is untouched. + * + * Similarly (and independently) for the face structure, + * - if eOrg->Lface == eDst->Lface, one loop is split into two + * - if eOrg->Lface != eDst->Lface, two distinct loops are joined into one + * In both cases, eDst->Lface is changed and eOrg->Lface is unaffected. + * + * __gl_meshDelete( eDel ) removes the edge eDel. There are several cases: + * if (eDel->Lface != eDel->Rface), we join two loops into one; the loop + * eDel->Lface is deleted. Otherwise, we are splitting one loop into two; + * the newly created loop will contain eDel->Dst. If the deletion of eDel + * would create isolated vertices, those are deleted as well. + * + * ********************** Other Edge Operations ************************** + * + * __gl_meshAddEdgeVertex( eOrg ) creates a new edge eNew such that + * eNew == eOrg->Lnext, and eNew->Dst is a newly created vertex. + * eOrg and eNew will have the same left face. + * + * __gl_meshSplitEdge( eOrg ) splits eOrg into two edges eOrg and eNew, + * such that eNew == eOrg->Lnext. The new vertex is eOrg->Dst == eNew->Org. + * eOrg and eNew will have the same left face. + * + * __gl_meshConnect( eOrg, eDst ) creates a new edge from eOrg->Dst + * to eDst->Org, and returns the corresponding half-edge eNew. + * If eOrg->Lface == eDst->Lface, this splits one loop into two, + * and the newly created loop is eNew->Lface. Otherwise, two disjoint + * loops are merged into one, and the loop eDst->Lface is destroyed. + * + * ************************ Other Operations ***************************** + * + * __gl_meshNewMesh() creates a new mesh with no edges, no vertices, + * and no loops (what we usually call a "face"). + * + * __gl_meshUnion( mesh1, mesh2 ) forms the union of all structures in + * both meshes, and returns the new mesh (the old meshes are destroyed). + * + * __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh. + * + * __gl_meshZapFace( fZap ) destroys a face and removes it from the + * global face list. All edges of fZap will have a NULL pointer as their + * left face. Any edges which also have a NULL pointer as their right face + * are deleted entirely (along with any isolated vertices this produces). + * An entire mesh can be deleted by zapping its faces, one at a time, + * in any order. Zapped faces cannot be used in further mesh operations! + * + * __gl_meshCheckMesh( mesh ) checks a mesh for self-consistency. + */ + +GLUhalfEdge *__gl_meshMakeEdge( GLUmesh *mesh ); +int __gl_meshSplice( GLUhalfEdge *eOrg, GLUhalfEdge *eDst ); +int __gl_meshDelete( GLUhalfEdge *eDel ); + +GLUhalfEdge *__gl_meshAddEdgeVertex( GLUhalfEdge *eOrg ); +GLUhalfEdge *__gl_meshSplitEdge( GLUhalfEdge *eOrg ); +GLUhalfEdge *__gl_meshConnect( GLUhalfEdge *eOrg, GLUhalfEdge *eDst ); + +GLUmesh *__gl_meshNewMesh( void ); +GLUmesh *__gl_meshUnion( GLUmesh *mesh1, GLUmesh *mesh2 ); +void __gl_meshDeleteMesh( GLUmesh *mesh ); +void __gl_meshZapFace( GLUface *fZap ); + +#ifdef NDEBUG +#define __gl_meshCheckMesh( mesh ) +#else +void __gl_meshCheckMesh( GLUmesh *mesh ); +#endif + +#endif diff --git a/GLU/normal.c b/GLU/normal.c new file mode 100644 index 0000000..0a2494b --- /dev/null +++ b/GLU/normal.c @@ -0,0 +1,253 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include "mesh.h" +#include "tess.h" +#include "normal.h" +#include +#include + +#define TRUE 1 +#define FALSE 0 + +#define Dot(u,v) (u[0]*v[0] + u[1]*v[1] + u[2]*v[2]) + +#if 0 +static void Normalize( GLdouble v[3] ) +{ + GLdouble len = v[0]*v[0] + v[1]*v[1] + v[2]*v[2]; + + assert( len > 0 ); + len = sqrt( len ); + v[0] /= len; + v[1] /= len; + v[2] /= len; +} +#endif + +#undef ABS +#define ABS(x) ((x) < 0 ? -(x) : (x)) + +static int LongAxis( GLdouble v[3] ) +{ + int i = 0; + + if( ABS(v[1]) > ABS(v[0]) ) { i = 1; } + if( ABS(v[2]) > ABS(v[i]) ) { i = 2; } + return i; +} + +static void ComputeNormal( GLUtesselator *tess, GLdouble norm[3] ) +{ + GLUvertex *v, *v1, *v2; + GLdouble c, tLen2, maxLen2; + GLdouble maxVal[3], minVal[3], d1[3], d2[3], tNorm[3]; + GLUvertex *maxVert[3], *minVert[3]; + GLUvertex *vHead = &tess->mesh->vHead; + int i; + + maxVal[0] = maxVal[1] = maxVal[2] = -2 * GLU_TESS_MAX_COORD; + minVal[0] = minVal[1] = minVal[2] = 2 * GLU_TESS_MAX_COORD; + + for( v = vHead->next; v != vHead; v = v->next ) { + for( i = 0; i < 3; ++i ) { + c = v->coords[i]; + if( c < minVal[i] ) { minVal[i] = c; minVert[i] = v; } + if( c > maxVal[i] ) { maxVal[i] = c; maxVert[i] = v; } + } + } + + /* Find two vertices separated by at least 1/sqrt(3) of the maximum + * distance between any two vertices + */ + i = 0; + if( maxVal[1] - minVal[1] > maxVal[0] - minVal[0] ) { i = 1; } + if( maxVal[2] - minVal[2] > maxVal[i] - minVal[i] ) { i = 2; } + if( minVal[i] >= maxVal[i] ) { + /* All vertices are the same -- normal doesn't matter */ + norm[0] = 0; norm[1] = 0; norm[2] = 1; + return; + } + + /* Look for a third vertex which forms the triangle with maximum area + * (Length of normal == twice the triangle area) + */ + maxLen2 = 0; + v1 = minVert[i]; + v2 = maxVert[i]; + d1[0] = v1->coords[0] - v2->coords[0]; + d1[1] = v1->coords[1] - v2->coords[1]; + d1[2] = v1->coords[2] - v2->coords[2]; + for( v = vHead->next; v != vHead; v = v->next ) { + d2[0] = v->coords[0] - v2->coords[0]; + d2[1] = v->coords[1] - v2->coords[1]; + d2[2] = v->coords[2] - v2->coords[2]; + tNorm[0] = d1[1]*d2[2] - d1[2]*d2[1]; + tNorm[1] = d1[2]*d2[0] - d1[0]*d2[2]; + tNorm[2] = d1[0]*d2[1] - d1[1]*d2[0]; + tLen2 = tNorm[0]*tNorm[0] + tNorm[1]*tNorm[1] + tNorm[2]*tNorm[2]; + if( tLen2 > maxLen2 ) { + maxLen2 = tLen2; + norm[0] = tNorm[0]; + norm[1] = tNorm[1]; + norm[2] = tNorm[2]; + } + } + + if( maxLen2 <= 0 ) { + /* All points lie on a single line -- any decent normal will do */ + norm[0] = norm[1] = norm[2] = 0; + norm[LongAxis(d1)] = 1; + } +} + + +static void CheckOrientation( GLUtesselator *tess ) +{ + GLdouble area; + GLUface *f, *fHead = &tess->mesh->fHead; + GLUvertex *v, *vHead = &tess->mesh->vHead; + GLUhalfEdge *e; + + /* When we compute the normal automatically, we choose the orientation + * so that the the sum of the signed areas of all contours is non-negative. + */ + area = 0; + for( f = fHead->next; f != fHead; f = f->next ) { + e = f->anEdge; + if( e->winding <= 0 ) continue; + do { + area += (e->Org->s - e->Dst->s) * (e->Org->t + e->Dst->t); + e = e->Lnext; + } while( e != f->anEdge ); + } + if( area < 0 ) { + /* Reverse the orientation by flipping all the t-coordinates */ + for( v = vHead->next; v != vHead; v = v->next ) { + v->t = - v->t; + } + tess->tUnit[0] = - tess->tUnit[0]; + tess->tUnit[1] = - tess->tUnit[1]; + tess->tUnit[2] = - tess->tUnit[2]; + } +} + +#ifdef FOR_TRITE_TEST_PROGRAM +#include +extern int RandomSweep; +#define S_UNIT_X (RandomSweep ? (2*drand48()-1) : 1.0) +#define S_UNIT_Y (RandomSweep ? (2*drand48()-1) : 0.0) +#else +#if defined(SLANTED_SWEEP) +/* The "feature merging" is not intended to be complete. There are + * special cases where edges are nearly parallel to the sweep line + * which are not implemented. The algorithm should still behave + * robustly (ie. produce a reasonable tesselation) in the presence + * of such edges, however it may miss features which could have been + * merged. We could minimize this effect by choosing the sweep line + * direction to be something unusual (ie. not parallel to one of the + * coordinate axes). + */ +#define S_UNIT_X 0.50941539564955385 /* Pre-normalized */ +#define S_UNIT_Y 0.86052074622010633 +#else +#define S_UNIT_X 1.0 +#define S_UNIT_Y 0.0 +#endif +#endif + +/* Determine the polygon normal and project vertices onto the plane + * of the polygon. + */ +void __gl_projectPolygon( GLUtesselator *tess ) +{ + GLUvertex *v, *vHead = &tess->mesh->vHead; + GLdouble norm[3]; + GLdouble *sUnit, *tUnit; + int i, computedNormal = FALSE; + + norm[0] = tess->normal[0]; + norm[1] = tess->normal[1]; + norm[2] = tess->normal[2]; + if( norm[0] == 0 && norm[1] == 0 && norm[2] == 0 ) { + ComputeNormal( tess, norm ); + computedNormal = TRUE; + } + sUnit = tess->sUnit; + tUnit = tess->tUnit; + i = LongAxis( norm ); + +#if defined(FOR_TRITE_TEST_PROGRAM) || defined(TRUE_PROJECT) + /* Choose the initial sUnit vector to be approximately perpendicular + * to the normal. + */ + Normalize( norm ); + + sUnit[i] = 0; + sUnit[(i+1)%3] = S_UNIT_X; + sUnit[(i+2)%3] = S_UNIT_Y; + + /* Now make it exactly perpendicular */ + w = Dot( sUnit, norm ); + sUnit[0] -= w * norm[0]; + sUnit[1] -= w * norm[1]; + sUnit[2] -= w * norm[2]; + Normalize( sUnit ); + + /* Choose tUnit so that (sUnit,tUnit,norm) form a right-handed frame */ + tUnit[0] = norm[1]*sUnit[2] - norm[2]*sUnit[1]; + tUnit[1] = norm[2]*sUnit[0] - norm[0]*sUnit[2]; + tUnit[2] = norm[0]*sUnit[1] - norm[1]*sUnit[0]; + Normalize( tUnit ); +#else + /* Project perpendicular to a coordinate axis -- better numerically */ + sUnit[i] = 0; + sUnit[(i+1)%3] = S_UNIT_X; + sUnit[(i+2)%3] = S_UNIT_Y; + + tUnit[i] = 0; + tUnit[(i+1)%3] = (norm[i] > 0) ? -S_UNIT_Y : S_UNIT_Y; + tUnit[(i+2)%3] = (norm[i] > 0) ? S_UNIT_X : -S_UNIT_X; +#endif + + /* Project the vertices onto the sweep plane */ + for( v = vHead->next; v != vHead; v = v->next ) { + v->s = Dot( v->coords, sUnit ); + v->t = Dot( v->coords, tUnit ); + } + if( computedNormal ) { + CheckOrientation( tess ); + } +} diff --git a/GLU/normal.h b/GLU/normal.h new file mode 100644 index 0000000..c376ca4 --- /dev/null +++ b/GLU/normal.h @@ -0,0 +1,45 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __normal_h_ +#define __normal_h_ + +#include "tess.h" + +/* __gl_projectPolygon( tess ) determines the polygon normal + * and project vertices onto the plane of the polygon. + */ +void __gl_projectPolygon( GLUtesselator *tess ); + +#endif diff --git a/GLU/priorityq-heap.c b/GLU/priorityq-heap.c new file mode 100644 index 0000000..2d7d164 --- /dev/null +++ b/GLU/priorityq-heap.c @@ -0,0 +1,253 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include +#include +#include +#include "priorityq-heap.h" +#include "memalloc.h" + +#define INIT_SIZE 32 + +#define TRUE 1 +#define FALSE 0 + +#ifdef FOR_TRITE_TEST_PROGRAM +#define LEQ(x,y) (*pq->leq)(x,y) +#else +/* Violates modularity, but a little faster */ +#include "geom.h" +#define LEQ(x,y) VertLeq((GLUvertex *)x, (GLUvertex *)y) +#endif + +/* really __gl_pqHeapNewPriorityQ */ +PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) ) +{ + PriorityQ *pq = (PriorityQ *)memAlloc( sizeof( PriorityQ )); + if (pq == NULL) return NULL; + + pq->size = 0; + pq->max = INIT_SIZE; + pq->nodes = (PQnode *)memAlloc( (INIT_SIZE + 1) * sizeof(pq->nodes[0]) ); + if (pq->nodes == NULL) { + memFree(pq); + return NULL; + } + + pq->handles = (PQhandleElem *)memAlloc( (INIT_SIZE + 1) * sizeof(pq->handles[0]) ); + if (pq->handles == NULL) { + memFree(pq->nodes); + memFree(pq); + return NULL; + } + + pq->initialized = FALSE; + pq->freeList = 0; + pq->leq = leq; + + pq->nodes[1].handle = 1; /* so that Minimum() returns NULL */ + pq->handles[1].key = NULL; + return pq; +} + +/* really __gl_pqHeapDeletePriorityQ */ +void pqDeletePriorityQ( PriorityQ *pq ) +{ + memFree( pq->handles ); + memFree( pq->nodes ); + memFree( pq ); +} + + +static void FloatDown( PriorityQ *pq, long curr ) +{ + PQnode *n = pq->nodes; + PQhandleElem *h = pq->handles; + PQhandle hCurr, hChild; + long child; + + hCurr = n[curr].handle; + for( ;; ) { + child = curr << 1; + if( child < pq->size && LEQ( h[n[child+1].handle].key, + h[n[child].handle].key )) { + ++child; + } + + assert(child <= pq->max); + + hChild = n[child].handle; + if( child > pq->size || LEQ( h[hCurr].key, h[hChild].key )) { + n[curr].handle = hCurr; + h[hCurr].node = curr; + break; + } + n[curr].handle = hChild; + h[hChild].node = curr; + curr = child; + } +} + + +static void FloatUp( PriorityQ *pq, long curr ) +{ + PQnode *n = pq->nodes; + PQhandleElem *h = pq->handles; + PQhandle hCurr, hParent; + long parent; + + hCurr = n[curr].handle; + for( ;; ) { + parent = curr >> 1; + hParent = n[parent].handle; + if( parent == 0 || LEQ( h[hParent].key, h[hCurr].key )) { + n[curr].handle = hCurr; + h[hCurr].node = curr; + break; + } + n[curr].handle = hParent; + h[hParent].node = curr; + curr = parent; + } +} + +/* really __gl_pqHeapInit */ +void pqInit( PriorityQ *pq ) +{ + long i; + + /* This method of building a heap is O(n), rather than O(n lg n). */ + + for( i = pq->size; i >= 1; --i ) { + FloatDown( pq, i ); + } + pq->initialized = TRUE; +} + +/* really __gl_pqHeapInsert */ +/* returns LONG_MAX iff out of memory */ +PQhandle pqInsert( PriorityQ *pq, PQkey keyNew ) +{ + long curr; + PQhandle free; + + curr = ++ pq->size; + if( (curr*2) > pq->max ) { + PQnode *saveNodes= pq->nodes; + PQhandleElem *saveHandles= pq->handles; + + /* If the heap overflows, double its size. */ + pq->max <<= 1; + pq->nodes = (PQnode *)memRealloc( pq->nodes, + (size_t) + ((pq->max + 1) * sizeof( pq->nodes[0] ))); + if (pq->nodes == NULL) { + pq->nodes = saveNodes; /* restore ptr to free upon return */ + return LONG_MAX; + } + pq->handles = (PQhandleElem *)memRealloc( pq->handles, + (size_t) + ((pq->max + 1) * + sizeof( pq->handles[0] ))); + if (pq->handles == NULL) { + pq->handles = saveHandles; /* restore ptr to free upon return */ + return LONG_MAX; + } + } + + if( pq->freeList == 0 ) { + free = curr; + } else { + free = pq->freeList; + pq->freeList = pq->handles[free].node; + } + + pq->nodes[curr].handle = free; + pq->handles[free].node = curr; + pq->handles[free].key = keyNew; + + if( pq->initialized ) { + FloatUp( pq, curr ); + } + assert(free != LONG_MAX); + return free; +} + +/* really __gl_pqHeapExtractMin */ +PQkey pqExtractMin( PriorityQ *pq ) +{ + PQnode *n = pq->nodes; + PQhandleElem *h = pq->handles; + PQhandle hMin = n[1].handle; + PQkey min = h[hMin].key; + + if( pq->size > 0 ) { + n[1].handle = n[pq->size].handle; + h[n[1].handle].node = 1; + + h[hMin].key = NULL; + h[hMin].node = pq->freeList; + pq->freeList = hMin; + + if( -- pq->size > 0 ) { + FloatDown( pq, 1 ); + } + } + return min; +} + +/* really __gl_pqHeapDelete */ +void pqDelete( PriorityQ *pq, PQhandle hCurr ) +{ + PQnode *n = pq->nodes; + PQhandleElem *h = pq->handles; + long curr; + + assert( hCurr >= 1 && hCurr <= pq->max && h[hCurr].key != NULL ); + + curr = h[hCurr].node; + n[curr].handle = n[pq->size].handle; + h[n[curr].handle].node = curr; + + if( curr <= -- pq->size ) { + if( curr <= 1 || LEQ( h[n[curr>>1].handle].key, h[n[curr].handle].key )) { + FloatDown( pq, curr ); + } else { + FloatUp( pq, curr ); + } + } + h[hCurr].key = NULL; + h[hCurr].node = pq->freeList; + pq->freeList = hCurr; +} diff --git a/GLU/priorityq-heap.h b/GLU/priorityq-heap.h new file mode 100644 index 0000000..dc9aaef --- /dev/null +++ b/GLU/priorityq-heap.h @@ -0,0 +1,107 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __priorityq_heap_h_ +#define __priorityq_heap_h_ + +/* Use #define's so that another heap implementation can use this one */ + +#define PQkey PQHeapKey +#define PQhandle PQHeapHandle +#define PriorityQ PriorityQHeap + +#define pqNewPriorityQ(leq) __gl_pqHeapNewPriorityQ(leq) +#define pqDeletePriorityQ(pq) __gl_pqHeapDeletePriorityQ(pq) + +/* The basic operations are insertion of a new key (pqInsert), + * and examination/extraction of a key whose value is minimum + * (pqMinimum/pqExtractMin). Deletion is also allowed (pqDelete); + * for this purpose pqInsert returns a "handle" which is supplied + * as the argument. + * + * An initial heap may be created efficiently by calling pqInsert + * repeatedly, then calling pqInit. In any case pqInit must be called + * before any operations other than pqInsert are used. + * + * If the heap is empty, pqMinimum/pqExtractMin will return a NULL key. + * This may also be tested with pqIsEmpty. + */ +#define pqInit(pq) __gl_pqHeapInit(pq) +#define pqInsert(pq,key) __gl_pqHeapInsert(pq,key) +#define pqMinimum(pq) __gl_pqHeapMinimum(pq) +#define pqExtractMin(pq) __gl_pqHeapExtractMin(pq) +#define pqDelete(pq,handle) __gl_pqHeapDelete(pq,handle) +#define pqIsEmpty(pq) __gl_pqHeapIsEmpty(pq) + + +/* Since we support deletion the data structure is a little more + * complicated than an ordinary heap. "nodes" is the heap itself; + * active nodes are stored in the range 1..pq->size. When the + * heap exceeds its allocated size (pq->max), its size doubles. + * The children of node i are nodes 2i and 2i+1. + * + * Each node stores an index into an array "handles". Each handle + * stores a key, plus a pointer back to the node which currently + * represents that key (ie. nodes[handles[i].node].handle == i). + */ + +typedef void *PQkey; +typedef long PQhandle; +typedef struct PriorityQ PriorityQ; + +typedef struct { PQhandle handle; } PQnode; +typedef struct { PQkey key; PQhandle node; } PQhandleElem; + +struct PriorityQ { + PQnode *nodes; + PQhandleElem *handles; + long size, max; + PQhandle freeList; + int initialized; + int (*leq)(PQkey key1, PQkey key2); +}; + +PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) ); +void pqDeletePriorityQ( PriorityQ *pq ); + +void pqInit( PriorityQ *pq ); +PQhandle pqInsert( PriorityQ *pq, PQkey key ); +PQkey pqExtractMin( PriorityQ *pq ); +void pqDelete( PriorityQ *pq, PQhandle handle ); + + +#define __gl_pqHeapMinimum(pq) ((pq)->handles[(pq)->nodes[1].handle].key) +#define __gl_pqHeapIsEmpty(pq) ((pq)->size == 0) + +#endif diff --git a/GLU/priorityq-sort.h b/GLU/priorityq-sort.h new file mode 100644 index 0000000..746cf5f --- /dev/null +++ b/GLU/priorityq-sort.h @@ -0,0 +1,117 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __priorityq_sort_h_ +#define __priorityq_sort_h_ + +#include "priorityq-heap.h" + +#undef PQkey +#undef PQhandle +#undef PriorityQ +#undef pqNewPriorityQ +#undef pqDeletePriorityQ +#undef pqInit +#undef pqInsert +#undef pqMinimum +#undef pqExtractMin +#undef pqDelete +#undef pqIsEmpty + +/* Use #define's so that another heap implementation can use this one */ + +#define PQkey PQSortKey +#define PQhandle PQSortHandle +#define PriorityQ PriorityQSort + +#define pqNewPriorityQ(leq) __gl_pqSortNewPriorityQ(leq) +#define pqDeletePriorityQ(pq) __gl_pqSortDeletePriorityQ(pq) + +/* The basic operations are insertion of a new key (pqInsert), + * and examination/extraction of a key whose value is minimum + * (pqMinimum/pqExtractMin). Deletion is also allowed (pqDelete); + * for this purpose pqInsert returns a "handle" which is supplied + * as the argument. + * + * An initial heap may be created efficiently by calling pqInsert + * repeatedly, then calling pqInit. In any case pqInit must be called + * before any operations other than pqInsert are used. + * + * If the heap is empty, pqMinimum/pqExtractMin will return a NULL key. + * This may also be tested with pqIsEmpty. + */ +#define pqInit(pq) __gl_pqSortInit(pq) +#define pqInsert(pq,key) __gl_pqSortInsert(pq,key) +#define pqMinimum(pq) __gl_pqSortMinimum(pq) +#define pqExtractMin(pq) __gl_pqSortExtractMin(pq) +#define pqDelete(pq,handle) __gl_pqSortDelete(pq,handle) +#define pqIsEmpty(pq) __gl_pqSortIsEmpty(pq) + + +/* Since we support deletion the data structure is a little more + * complicated than an ordinary heap. "nodes" is the heap itself; + * active nodes are stored in the range 1..pq->size. When the + * heap exceeds its allocated size (pq->max), its size doubles. + * The children of node i are nodes 2i and 2i+1. + * + * Each node stores an index into an array "handles". Each handle + * stores a key, plus a pointer back to the node which currently + * represents that key (ie. nodes[handles[i].node].handle == i). + */ + +typedef PQHeapKey PQkey; +typedef PQHeapHandle PQhandle; +typedef struct PriorityQ PriorityQ; + +struct PriorityQ { + PriorityQHeap *heap; + PQkey *keys; + PQkey **order; + PQhandle size, max; + int initialized; + int (*leq)(PQkey key1, PQkey key2); +}; + +PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) ); +void pqDeletePriorityQ( PriorityQ *pq ); + +int pqInit( PriorityQ *pq ); +PQhandle pqInsert( PriorityQ *pq, PQkey key ); +PQkey pqExtractMin( PriorityQ *pq ); +void pqDelete( PriorityQ *pq, PQhandle handle ); + +PQkey pqMinimum( PriorityQ *pq ); +int pqIsEmpty( PriorityQ *pq ); + +#endif diff --git a/GLU/priorityq.c b/GLU/priorityq.c new file mode 100644 index 0000000..11f0263 --- /dev/null +++ b/GLU/priorityq.c @@ -0,0 +1,260 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include +#include /* LONG_MAX */ +#include "memalloc.h" + +/* Include all the code for the regular heap-based queue here. */ + +#include "priorityq-heap.c" + +/* Now redefine all the function names to map to their "Sort" versions. */ + +#include "priorityq-sort.h" + +/* really __gl_pqSortNewPriorityQ */ +PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) ) +{ + PriorityQ *pq = (PriorityQ *)memAlloc( sizeof( PriorityQ )); + if (pq == NULL) return NULL; + + pq->heap = __gl_pqHeapNewPriorityQ( leq ); + if (pq->heap == NULL) { + memFree(pq); + return NULL; + } + + pq->keys = (PQHeapKey *)memAlloc( INIT_SIZE * sizeof(pq->keys[0]) ); + if (pq->keys == NULL) { + __gl_pqHeapDeletePriorityQ(pq->heap); + memFree(pq); + return NULL; + } + + pq->size = 0; + pq->max = INIT_SIZE; + pq->initialized = FALSE; + pq->leq = leq; + return pq; +} + +/* really __gl_pqSortDeletePriorityQ */ +void pqDeletePriorityQ( PriorityQ *pq ) +{ + assert(pq != NULL); + if (pq->heap != NULL) __gl_pqHeapDeletePriorityQ( pq->heap ); + if (pq->order != NULL) memFree( pq->order ); + if (pq->keys != NULL) memFree( pq->keys ); + memFree( pq ); +} + + +#define LT(x,y) (! LEQ(y,x)) +#define GT(x,y) (! LEQ(x,y)) +#define Swap(a,b) if(1){PQkey *tmp = *a; *a = *b; *b = tmp;}else + +/* really __gl_pqSortInit */ +int pqInit( PriorityQ *pq ) +{ + PQkey **p, **r, **i, **j, *piv; + struct { PQkey **p, **r; } Stack[50], *top = Stack; + unsigned long seed = 2016473283; + + /* Create an array of indirect pointers to the keys, so that we + * the handles we have returned are still valid. + */ +/* + pq->order = (PQHeapKey **)memAlloc( (size_t) + (pq->size * sizeof(pq->order[0])) ); +*/ + pq->order = (PQHeapKey **)memAlloc( (size_t) + ((pq->size+1) * sizeof(pq->order[0])) ); +/* the previous line is a patch to compensate for the fact that IBM */ +/* machines return a null on a malloc of zero bytes (unlike SGI), */ +/* so we have to put in this defense to guard against a memory */ +/* fault four lines down. from fossum@austin.ibm.com. */ + if (pq->order == NULL) return 0; + + p = pq->order; + r = p + pq->size - 1; + for( piv = pq->keys, i = p; i <= r; ++piv, ++i ) { + *i = piv; + } + + /* Sort the indirect pointers in descending order, + * using randomized Quicksort + */ + top->p = p; top->r = r; ++top; + while( --top >= Stack ) { + p = top->p; + r = top->r; + while( r > p + 10 ) { + seed = seed * 1539415821 + 1; + i = p + seed % (r - p + 1); + piv = *i; + *i = *p; + *p = piv; + i = p - 1; + j = r + 1; + do { + do { ++i; } while( GT( **i, *piv )); + do { --j; } while( LT( **j, *piv )); + Swap( i, j ); + } while( i < j ); + Swap( i, j ); /* Undo last swap */ + if( i - p < r - j ) { + top->p = j+1; top->r = r; ++top; + r = i-1; + } else { + top->p = p; top->r = i-1; ++top; + p = j+1; + } + } + /* Insertion sort small lists */ + for( i = p+1; i <= r; ++i ) { + piv = *i; + for( j = i; j > p && LT( **(j-1), *piv ); --j ) { + *j = *(j-1); + } + *j = piv; + } + } + pq->max = pq->size; + pq->initialized = TRUE; + __gl_pqHeapInit( pq->heap ); /* always succeeds */ + +#ifndef NDEBUG + p = pq->order; + r = p + pq->size - 1; + for( i = p; i < r; ++i ) { + assert( LEQ( **(i+1), **i )); + } +#endif + + return 1; +} + +/* really __gl_pqSortInsert */ +/* returns LONG_MAX iff out of memory */ +PQhandle pqInsert( PriorityQ *pq, PQkey keyNew ) +{ + long curr; + + if( pq->initialized ) { + return __gl_pqHeapInsert( pq->heap, keyNew ); + } + curr = pq->size; + if( ++ pq->size >= pq->max ) { + PQkey *saveKey= pq->keys; + + /* If the heap overflows, double its size. */ + pq->max <<= 1; + pq->keys = (PQHeapKey *)memRealloc( pq->keys, + (size_t) + (pq->max * sizeof( pq->keys[0] ))); + if (pq->keys == NULL) { + pq->keys = saveKey; /* restore ptr to free upon return */ + return LONG_MAX; + } + } + assert(curr != LONG_MAX); + pq->keys[curr] = keyNew; + + /* Negative handles index the sorted array. */ + return -(curr+1); +} + +/* really __gl_pqSortExtractMin */ +PQkey pqExtractMin( PriorityQ *pq ) +{ + PQkey sortMin, heapMin; + + if( pq->size == 0 ) { + return __gl_pqHeapExtractMin( pq->heap ); + } + sortMin = *(pq->order[pq->size-1]); + if( ! __gl_pqHeapIsEmpty( pq->heap )) { + heapMin = __gl_pqHeapMinimum( pq->heap ); + if( LEQ( heapMin, sortMin )) { + return __gl_pqHeapExtractMin( pq->heap ); + } + } + do { + -- pq->size; + } while( pq->size > 0 && *(pq->order[pq->size-1]) == NULL ); + return sortMin; +} + +/* really __gl_pqSortMinimum */ +PQkey pqMinimum( PriorityQ *pq ) +{ + PQkey sortMin, heapMin; + + if( pq->size == 0 ) { + return __gl_pqHeapMinimum( pq->heap ); + } + sortMin = *(pq->order[pq->size-1]); + if( ! __gl_pqHeapIsEmpty( pq->heap )) { + heapMin = __gl_pqHeapMinimum( pq->heap ); + if( LEQ( heapMin, sortMin )) { + return heapMin; + } + } + return sortMin; +} + +/* really __gl_pqSortIsEmpty */ +int pqIsEmpty( PriorityQ *pq ) +{ + return (pq->size == 0) && __gl_pqHeapIsEmpty( pq->heap ); +} + +/* really __gl_pqSortDelete */ +void pqDelete( PriorityQ *pq, PQhandle curr ) +{ + if( curr >= 0 ) { + __gl_pqHeapDelete( pq->heap, curr ); + return; + } + curr = -(curr+1); + assert( curr < pq->max && pq->keys[curr] != NULL ); + + pq->keys[curr] = NULL; + while( pq->size > 0 && *(pq->order[pq->size-1]) == NULL ) { + -- pq->size; + } +} diff --git a/GLU/priorityq.h b/GLU/priorityq.h new file mode 100644 index 0000000..746cf5f --- /dev/null +++ b/GLU/priorityq.h @@ -0,0 +1,117 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __priorityq_sort_h_ +#define __priorityq_sort_h_ + +#include "priorityq-heap.h" + +#undef PQkey +#undef PQhandle +#undef PriorityQ +#undef pqNewPriorityQ +#undef pqDeletePriorityQ +#undef pqInit +#undef pqInsert +#undef pqMinimum +#undef pqExtractMin +#undef pqDelete +#undef pqIsEmpty + +/* Use #define's so that another heap implementation can use this one */ + +#define PQkey PQSortKey +#define PQhandle PQSortHandle +#define PriorityQ PriorityQSort + +#define pqNewPriorityQ(leq) __gl_pqSortNewPriorityQ(leq) +#define pqDeletePriorityQ(pq) __gl_pqSortDeletePriorityQ(pq) + +/* The basic operations are insertion of a new key (pqInsert), + * and examination/extraction of a key whose value is minimum + * (pqMinimum/pqExtractMin). Deletion is also allowed (pqDelete); + * for this purpose pqInsert returns a "handle" which is supplied + * as the argument. + * + * An initial heap may be created efficiently by calling pqInsert + * repeatedly, then calling pqInit. In any case pqInit must be called + * before any operations other than pqInsert are used. + * + * If the heap is empty, pqMinimum/pqExtractMin will return a NULL key. + * This may also be tested with pqIsEmpty. + */ +#define pqInit(pq) __gl_pqSortInit(pq) +#define pqInsert(pq,key) __gl_pqSortInsert(pq,key) +#define pqMinimum(pq) __gl_pqSortMinimum(pq) +#define pqExtractMin(pq) __gl_pqSortExtractMin(pq) +#define pqDelete(pq,handle) __gl_pqSortDelete(pq,handle) +#define pqIsEmpty(pq) __gl_pqSortIsEmpty(pq) + + +/* Since we support deletion the data structure is a little more + * complicated than an ordinary heap. "nodes" is the heap itself; + * active nodes are stored in the range 1..pq->size. When the + * heap exceeds its allocated size (pq->max), its size doubles. + * The children of node i are nodes 2i and 2i+1. + * + * Each node stores an index into an array "handles". Each handle + * stores a key, plus a pointer back to the node which currently + * represents that key (ie. nodes[handles[i].node].handle == i). + */ + +typedef PQHeapKey PQkey; +typedef PQHeapHandle PQhandle; +typedef struct PriorityQ PriorityQ; + +struct PriorityQ { + PriorityQHeap *heap; + PQkey *keys; + PQkey **order; + PQhandle size, max; + int initialized; + int (*leq)(PQkey key1, PQkey key2); +}; + +PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) ); +void pqDeletePriorityQ( PriorityQ *pq ); + +int pqInit( PriorityQ *pq ); +PQhandle pqInsert( PriorityQ *pq, PQkey key ); +PQkey pqExtractMin( PriorityQ *pq ); +void pqDelete( PriorityQ *pq, PQhandle handle ); + +PQkey pqMinimum( PriorityQ *pq ); +int pqIsEmpty( PriorityQ *pq ); + +#endif diff --git a/GLU/render.c b/GLU/render.c new file mode 100644 index 0000000..4f376f7 --- /dev/null +++ b/GLU/render.c @@ -0,0 +1,498 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include +#include "mesh.h" +#include "tess.h" +#include "render.h" + +#define TRUE 1 +#define FALSE 0 + +/* This structure remembers the information we need about a primitive + * to be able to render it later, once we have determined which + * primitive is able to use the most triangles. + */ +struct FaceCount { + long size; /* number of triangles used */ + GLUhalfEdge *eStart; /* edge where this primitive starts */ + void (*render)(GLUtesselator *, GLUhalfEdge *, long); + /* routine to render this primitive */ +}; + +static struct FaceCount MaximumFan( GLUhalfEdge *eOrig ); +static struct FaceCount MaximumStrip( GLUhalfEdge *eOrig ); + +static void RenderFan( GLUtesselator *tess, GLUhalfEdge *eStart, long size ); +static void RenderStrip( GLUtesselator *tess, GLUhalfEdge *eStart, long size ); +static void RenderTriangle( GLUtesselator *tess, GLUhalfEdge *eStart, + long size ); + +static void RenderMaximumFaceGroup( GLUtesselator *tess, GLUface *fOrig ); +static void RenderLonelyTriangles( GLUtesselator *tess, GLUface *head ); + + + +/************************ Strips and Fans decomposition ******************/ + +/* __gl_renderMesh( tess, mesh ) takes a mesh and breaks it into triangle + * fans, strips, and separate triangles. A substantial effort is made + * to use as few rendering primitives as possible (ie. to make the fans + * and strips as large as possible). + * + * The rendering output is provided as callbacks (see the api). + */ +void __gl_renderMesh( GLUtesselator *tess, GLUmesh *mesh ) +{ + GLUface *f; + + /* Make a list of separate triangles so we can render them all at once */ + tess->lonelyTriList = NULL; + + for( f = mesh->fHead.next; f != &mesh->fHead; f = f->next ) { + f->marked = FALSE; + } + for( f = mesh->fHead.next; f != &mesh->fHead; f = f->next ) { + + /* We examine all faces in an arbitrary order. Whenever we find + * an unprocessed face F, we output a group of faces including F + * whose size is maximum. + */ + if( f->inside && ! f->marked ) { + RenderMaximumFaceGroup( tess, f ); + assert( f->marked ); + } + } + if( tess->lonelyTriList != NULL ) { + RenderLonelyTriangles( tess, tess->lonelyTriList ); + tess->lonelyTriList = NULL; + } +} + + +static void RenderMaximumFaceGroup( GLUtesselator *tess, GLUface *fOrig ) +{ + /* We want to find the largest triangle fan or strip of unmarked faces + * which includes the given face fOrig. There are 3 possible fans + * passing through fOrig (one centered at each vertex), and 3 possible + * strips (one for each CCW permutation of the vertices). Our strategy + * is to try all of these, and take the primitive which uses the most + * triangles (a greedy approach). + */ + GLUhalfEdge *e = fOrig->anEdge; + struct FaceCount max, newFace; + + max.size = 1; + max.eStart = e; + max.render = &RenderTriangle; + + if( ! tess->flagBoundary ) { + newFace = MaximumFan( e ); if( newFace.size > max.size ) { max = newFace; } + newFace = MaximumFan( e->Lnext ); if( newFace.size > max.size ) { max = newFace; } + newFace = MaximumFan( e->Lprev ); if( newFace.size > max.size ) { max = newFace; } + + newFace = MaximumStrip( e ); if( newFace.size > max.size ) { max = newFace; } + newFace = MaximumStrip( e->Lnext ); if( newFace.size > max.size ) { max = newFace; } + newFace = MaximumStrip( e->Lprev ); if( newFace.size > max.size ) { max = newFace; } + } + (*(max.render))( tess, max.eStart, max.size ); +} + + +/* Macros which keep track of faces we have marked temporarily, and allow + * us to backtrack when necessary. With triangle fans, this is not + * really necessary, since the only awkward case is a loop of triangles + * around a single origin vertex. However with strips the situation is + * more complicated, and we need a general tracking method like the + * one here. + */ +#define Marked(f) (! (f)->inside || (f)->marked) + +#define AddToTrail(f,t) ((f)->trail = (t), (t) = (f), (f)->marked = TRUE) + +#define FreeTrail(t) if( 1 ) { \ + while( (t) != NULL ) { \ + (t)->marked = FALSE; t = (t)->trail; \ + } \ + } else /* absorb trailing semicolon */ + + + +static struct FaceCount MaximumFan( GLUhalfEdge *eOrig ) +{ + /* eOrig->Lface is the face we want to render. We want to find the size + * of a maximal fan around eOrig->Org. To do this we just walk around + * the origin vertex as far as possible in both directions. + */ + struct FaceCount newFace = { 0, NULL, &RenderFan }; + GLUface *trail = NULL; + GLUhalfEdge *e; + + for( e = eOrig; ! Marked( e->Lface ); e = e->Onext ) { + AddToTrail( e->Lface, trail ); + ++newFace.size; + } + for( e = eOrig; ! Marked( e->Rface ); e = e->Oprev ) { + AddToTrail( e->Rface, trail ); + ++newFace.size; + } + newFace.eStart = e; + /*LINTED*/ + FreeTrail( trail ); + return newFace; +} + + +#define IsEven(n) (((n) & 1) == 0) + +static struct FaceCount MaximumStrip( GLUhalfEdge *eOrig ) +{ + /* Here we are looking for a maximal strip that contains the vertices + * eOrig->Org, eOrig->Dst, eOrig->Lnext->Dst (in that order or the + * reverse, such that all triangles are oriented CCW). + * + * Again we walk forward and backward as far as possible. However for + * strips there is a twist: to get CCW orientations, there must be + * an *even* number of triangles in the strip on one side of eOrig. + * We walk the strip starting on a side with an even number of triangles; + * if both side have an odd number, we are forced to shorten one side. + */ + struct FaceCount newFace = { 0, NULL, &RenderStrip }; + long headSize = 0, tailSize = 0; + GLUface *trail = NULL; + GLUhalfEdge *e, *eTail, *eHead; + + for( e = eOrig; ! Marked( e->Lface ); ++tailSize, e = e->Onext ) { + AddToTrail( e->Lface, trail ); + ++tailSize; + e = e->Dprev; + if( Marked( e->Lface )) break; + AddToTrail( e->Lface, trail ); + } + eTail = e; + + for( e = eOrig; ! Marked( e->Rface ); ++headSize, e = e->Dnext ) { + AddToTrail( e->Rface, trail ); + ++headSize; + e = e->Oprev; + if( Marked( e->Rface )) break; + AddToTrail( e->Rface, trail ); + } + eHead = e; + + newFace.size = tailSize + headSize; + if( IsEven( tailSize )) { + newFace.eStart = eTail->Sym; + } else if( IsEven( headSize )) { + newFace.eStart = eHead; + } else { + /* Both sides have odd length, we must shorten one of them. In fact, + * we must start from eHead to guarantee inclusion of eOrig->Lface. + */ + --newFace.size; + newFace.eStart = eHead->Onext; + } + /*LINTED*/ + FreeTrail( trail ); + return newFace; +} + + +static void RenderTriangle( GLUtesselator *tess, GLUhalfEdge *e, long size ) +{ + /* Just add the triangle to a triangle list, so we can render all + * the separate triangles at once. + */ + assert( size == 1 ); + AddToTrail( e->Lface, tess->lonelyTriList ); +} + + +static void RenderLonelyTriangles( GLUtesselator *tess, GLUface *f ) +{ + /* Now we render all the separate triangles which could not be + * grouped into a triangle fan or strip. + */ + GLUhalfEdge *e; + int newState; + int edgeState = -1; /* force edge state output for first vertex */ + + CALL_BEGIN_OR_BEGIN_DATA( GL_TRIANGLES ); + + for( ; f != NULL; f = f->trail ) { + /* Loop once for each edge (there will always be 3 edges) */ + + e = f->anEdge; + do { + if( tess->flagBoundary ) { + /* Set the "edge state" to TRUE just before we output the + * first vertex of each edge on the polygon boundary. + */ + newState = ! e->Rface->inside; + if( edgeState != newState ) { + edgeState = newState; + CALL_EDGE_FLAG_OR_EDGE_FLAG_DATA( edgeState ); + } + } + CALL_VERTEX_OR_VERTEX_DATA( e->Org->data ); + + e = e->Lnext; + } while( e != f->anEdge ); + } + CALL_END_OR_END_DATA(); +} + + +static void RenderFan( GLUtesselator *tess, GLUhalfEdge *e, long size ) +{ + /* Render as many CCW triangles as possible in a fan starting from + * edge "e". The fan *should* contain exactly "size" triangles + * (otherwise we've goofed up somewhere). + */ + CALL_BEGIN_OR_BEGIN_DATA( GL_TRIANGLE_FAN ); + CALL_VERTEX_OR_VERTEX_DATA( e->Org->data ); + CALL_VERTEX_OR_VERTEX_DATA( e->Dst->data ); + + while( ! Marked( e->Lface )) { + e->Lface->marked = TRUE; + --size; + e = e->Onext; + CALL_VERTEX_OR_VERTEX_DATA( e->Dst->data ); + } + + assert( size == 0 ); + CALL_END_OR_END_DATA(); +} + + +static void RenderStrip( GLUtesselator *tess, GLUhalfEdge *e, long size ) +{ + /* Render as many CCW triangles as possible in a strip starting from + * edge "e". The strip *should* contain exactly "size" triangles + * (otherwise we've goofed up somewhere). + */ + CALL_BEGIN_OR_BEGIN_DATA( GL_TRIANGLE_STRIP ); + CALL_VERTEX_OR_VERTEX_DATA( e->Org->data ); + CALL_VERTEX_OR_VERTEX_DATA( e->Dst->data ); + + while( ! Marked( e->Lface )) { + e->Lface->marked = TRUE; + --size; + e = e->Dprev; + CALL_VERTEX_OR_VERTEX_DATA( e->Org->data ); + if( Marked( e->Lface )) break; + + e->Lface->marked = TRUE; + --size; + e = e->Onext; + CALL_VERTEX_OR_VERTEX_DATA( e->Dst->data ); + } + + assert( size == 0 ); + CALL_END_OR_END_DATA(); +} + + +/************************ Boundary contour decomposition ******************/ + +/* __gl_renderBoundary( tess, mesh ) takes a mesh, and outputs one + * contour for each face marked "inside". The rendering output is + * provided as callbacks (see the api). + */ +void __gl_renderBoundary( GLUtesselator *tess, GLUmesh *mesh ) +{ + GLUface *f; + GLUhalfEdge *e; + + for( f = mesh->fHead.next; f != &mesh->fHead; f = f->next ) { + if( f->inside ) { + CALL_BEGIN_OR_BEGIN_DATA( GL_LINE_LOOP ); + e = f->anEdge; + do { + CALL_VERTEX_OR_VERTEX_DATA( e->Org->data ); + e = e->Lnext; + } while( e != f->anEdge ); + CALL_END_OR_END_DATA(); + } + } +} + + +/************************ Quick-and-dirty decomposition ******************/ + +#define SIGN_INCONSISTENT 2 + +static int ComputeNormal( GLUtesselator *tess, GLdouble norm[3], int check ) +/* + * If check==FALSE, we compute the polygon normal and place it in norm[]. + * If check==TRUE, we check that each triangle in the fan from v0 has a + * consistent orientation with respect to norm[]. If triangles are + * consistently oriented CCW, return 1; if CW, return -1; if all triangles + * are degenerate return 0; otherwise (no consistent orientation) return + * SIGN_INCONSISTENT. + */ +{ + CachedVertex *v0 = tess->cache; + CachedVertex *vn = v0 + tess->cacheCount; + CachedVertex *vc; + GLdouble dot, xc, yc, zc, xp, yp, zp, n[3]; + int sign = 0; + + /* Find the polygon normal. It is important to get a reasonable + * normal even when the polygon is self-intersecting (eg. a bowtie). + * Otherwise, the computed normal could be very tiny, but perpendicular + * to the true plane of the polygon due to numerical noise. Then all + * the triangles would appear to be degenerate and we would incorrectly + * decompose the polygon as a fan (or simply not render it at all). + * + * We use a sum-of-triangles normal algorithm rather than the more + * efficient sum-of-trapezoids method (used in CheckOrientation() + * in normal.c). This lets us explicitly reverse the signed area + * of some triangles to get a reasonable normal in the self-intersecting + * case. + */ + if( ! check ) { + norm[0] = norm[1] = norm[2] = 0.0; + } + + vc = v0 + 1; + xc = vc->coords[0] - v0->coords[0]; + yc = vc->coords[1] - v0->coords[1]; + zc = vc->coords[2] - v0->coords[2]; + while( ++vc < vn ) { + xp = xc; yp = yc; zp = zc; + xc = vc->coords[0] - v0->coords[0]; + yc = vc->coords[1] - v0->coords[1]; + zc = vc->coords[2] - v0->coords[2]; + + /* Compute (vp - v0) cross (vc - v0) */ + n[0] = yp*zc - zp*yc; + n[1] = zp*xc - xp*zc; + n[2] = xp*yc - yp*xc; + + dot = n[0]*norm[0] + n[1]*norm[1] + n[2]*norm[2]; + if( ! check ) { + /* Reverse the contribution of back-facing triangles to get + * a reasonable normal for self-intersecting polygons (see above) + */ + if( dot >= 0 ) { + norm[0] += n[0]; norm[1] += n[1]; norm[2] += n[2]; + } else { + norm[0] -= n[0]; norm[1] -= n[1]; norm[2] -= n[2]; + } + } else if( dot != 0 ) { + /* Check the new orientation for consistency with previous triangles */ + if( dot > 0 ) { + if( sign < 0 ) return SIGN_INCONSISTENT; + sign = 1; + } else { + if( sign > 0 ) return SIGN_INCONSISTENT; + sign = -1; + } + } + } + return sign; +} + +/* __gl_renderCache( tess ) takes a single contour and tries to render it + * as a triangle fan. This handles convex polygons, as well as some + * non-convex polygons if we get lucky. + * + * Returns TRUE if the polygon was successfully rendered. The rendering + * output is provided as callbacks (see the api). + */ +GLboolean __gl_renderCache( GLUtesselator *tess ) +{ + CachedVertex *v0 = tess->cache; + CachedVertex *vn = v0 + tess->cacheCount; + CachedVertex *vc; + GLdouble norm[3]; + int sign; + + if( tess->cacheCount < 3 ) { + /* Degenerate contour -- no output */ + return TRUE; + } + + norm[0] = tess->normal[0]; + norm[1] = tess->normal[1]; + norm[2] = tess->normal[2]; + if( norm[0] == 0 && norm[1] == 0 && norm[2] == 0 ) { + ComputeNormal( tess, norm, FALSE ); + } + + sign = ComputeNormal( tess, norm, TRUE ); + if( sign == SIGN_INCONSISTENT ) { + /* Fan triangles did not have a consistent orientation */ + return FALSE; + } + if( sign == 0 ) { + /* All triangles were degenerate */ + return TRUE; + } + + /* Make sure we do the right thing for each winding rule */ + switch( tess->windingRule ) { + case GLU_TESS_WINDING_ODD: + case GLU_TESS_WINDING_NONZERO: + break; + case GLU_TESS_WINDING_POSITIVE: + if( sign < 0 ) return TRUE; + break; + case GLU_TESS_WINDING_NEGATIVE: + if( sign > 0 ) return TRUE; + break; + case GLU_TESS_WINDING_ABS_GEQ_TWO: + return TRUE; + } + + CALL_BEGIN_OR_BEGIN_DATA( tess->boundaryOnly ? GL_LINE_LOOP + : (tess->cacheCount > 3) ? GL_TRIANGLE_FAN + : GL_TRIANGLES ); + + CALL_VERTEX_OR_VERTEX_DATA( v0->data ); + if( sign > 0 ) { + for( vc = v0+1; vc < vn; ++vc ) { + CALL_VERTEX_OR_VERTEX_DATA( vc->data ); + } + } else { + for( vc = vn-1; vc > v0; --vc ) { + CALL_VERTEX_OR_VERTEX_DATA( vc->data ); + } + } + CALL_END_OR_END_DATA(); + return TRUE; +} diff --git a/GLU/render.h b/GLU/render.h new file mode 100644 index 0000000..a298c9a --- /dev/null +++ b/GLU/render.h @@ -0,0 +1,52 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __render_h_ +#define __render_h_ + +#include "mesh.h" + +/* __gl_renderMesh( tess, mesh ) takes a mesh and breaks it into triangle + * fans, strips, and separate triangles. A substantial effort is made + * to use as few rendering primitives as possible (ie. to make the fans + * and strips as large as possible). + * + * The rendering output is provided as callbacks (see the api). + */ +void __gl_renderMesh( GLUtesselator *tess, GLUmesh *mesh ); +void __gl_renderBoundary( GLUtesselator *tess, GLUmesh *mesh ); + +GLboolean __gl_renderCache( GLUtesselator *tess ); + +#endif diff --git a/GLU/sweep.c b/GLU/sweep.c new file mode 100644 index 0000000..744be6b --- /dev/null +++ b/GLU/sweep.c @@ -0,0 +1,1357 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include +#include /* longjmp */ +#include /* LONG_MAX */ + +#include "mesh.h" +#include "geom.h" +#include "tess.h" +#include "dict.h" +#include "priorityq.h" +#include "memalloc.h" +#include "sweep.h" + +#define TRUE 1 +#define FALSE 0 + +#ifdef FOR_TRITE_TEST_PROGRAM +extern void DebugEvent( GLUtesselator *tess ); +#else +#define DebugEvent( tess ) +#endif + +/* + * Invariants for the Edge Dictionary. + * - each pair of adjacent edges e2=Succ(e1) satisfies EdgeLeq(e1,e2) + * at any valid location of the sweep event + * - if EdgeLeq(e2,e1) as well (at any valid sweep event), then e1 and e2 + * share a common endpoint + * - for each e, e->Dst has been processed, but not e->Org + * - each edge e satisfies VertLeq(e->Dst,event) && VertLeq(event,e->Org) + * where "event" is the current sweep line event. + * - no edge e has zero length + * + * Invariants for the Mesh (the processed portion). + * - the portion of the mesh left of the sweep line is a planar graph, + * ie. there is *some* way to embed it in the plane + * - no processed edge has zero length + * - no two processed vertices have identical coordinates + * - each "inside" region is monotone, ie. can be broken into two chains + * of monotonically increasing vertices according to VertLeq(v1,v2) + * - a non-invariant: these chains may intersect (very slightly) + * + * Invariants for the Sweep. + * - if none of the edges incident to the event vertex have an activeRegion + * (ie. none of these edges are in the edge dictionary), then the vertex + * has only right-going edges. + * - if an edge is marked "fixUpperEdge" (it is a temporary edge introduced + * by ConnectRightVertex), then it is the only right-going edge from + * its associated vertex. (This says that these edges exist only + * when it is necessary.) + */ + +#undef MAX +#undef MIN +#define MAX(x,y) ((x) >= (y) ? (x) : (y)) +#define MIN(x,y) ((x) <= (y) ? (x) : (y)) + +/* When we merge two edges into one, we need to compute the combined + * winding of the new edge. + */ +#define AddWinding(eDst,eSrc) (eDst->winding += eSrc->winding, \ + eDst->Sym->winding += eSrc->Sym->winding) + +static void SweepEvent( GLUtesselator *tess, GLUvertex *vEvent ); +static void WalkDirtyRegions( GLUtesselator *tess, ActiveRegion *regUp ); +static int CheckForRightSplice( GLUtesselator *tess, ActiveRegion *regUp ); + +static int EdgeLeq( GLUtesselator *tess, ActiveRegion *reg1, + ActiveRegion *reg2 ) +/* + * Both edges must be directed from right to left (this is the canonical + * direction for the upper edge of each region). + * + * The strategy is to evaluate a "t" value for each edge at the + * current sweep line position, given by tess->event. The calculations + * are designed to be very stable, but of course they are not perfect. + * + * Special case: if both edge destinations are at the sweep event, + * we sort the edges by slope (they would otherwise compare equally). + */ +{ + GLUvertex *event = tess->event; + GLUhalfEdge *e1, *e2; + GLdouble t1, t2; + + e1 = reg1->eUp; + e2 = reg2->eUp; + + if( e1->Dst == event ) { + if( e2->Dst == event ) { + /* Two edges right of the sweep line which meet at the sweep event. + * Sort them by slope. + */ + if( VertLeq( e1->Org, e2->Org )) { + return EdgeSign( e2->Dst, e1->Org, e2->Org ) <= 0; + } + return EdgeSign( e1->Dst, e2->Org, e1->Org ) >= 0; + } + return EdgeSign( e2->Dst, event, e2->Org ) <= 0; + } + if( e2->Dst == event ) { + return EdgeSign( e1->Dst, event, e1->Org ) >= 0; + } + + /* General case - compute signed distance *from* e1, e2 to event */ + t1 = EdgeEval( e1->Dst, event, e1->Org ); + t2 = EdgeEval( e2->Dst, event, e2->Org ); + return (t1 >= t2); +} + + +static void DeleteRegion( GLUtesselator *tess, ActiveRegion *reg ) +{ + if( reg->fixUpperEdge ) { + /* It was created with zero winding number, so it better be + * deleted with zero winding number (ie. it better not get merged + * with a real edge). + */ + assert( reg->eUp->winding == 0 ); + } + reg->eUp->activeRegion = NULL; + dictDelete( tess->dict, reg->nodeUp ); /* __gl_dictListDelete */ + memFree( reg ); +} + + +static int FixUpperEdge( ActiveRegion *reg, GLUhalfEdge *newEdge ) +/* + * Replace an upper edge which needs fixing (see ConnectRightVertex). + */ +{ + assert( reg->fixUpperEdge ); + if ( !__gl_meshDelete( reg->eUp ) ) return 0; + reg->fixUpperEdge = FALSE; + reg->eUp = newEdge; + newEdge->activeRegion = reg; + + return 1; +} + +static ActiveRegion *TopLeftRegion( ActiveRegion *reg ) +{ + GLUvertex *org = reg->eUp->Org; + GLUhalfEdge *e; + + /* Find the region above the uppermost edge with the same origin */ + do { + reg = RegionAbove( reg ); + } while( reg->eUp->Org == org ); + + /* If the edge above was a temporary edge introduced by ConnectRightVertex, + * now is the time to fix it. + */ + if( reg->fixUpperEdge ) { + e = __gl_meshConnect( RegionBelow(reg)->eUp->Sym, reg->eUp->Lnext ); + if (e == NULL) return NULL; + if ( !FixUpperEdge( reg, e ) ) return NULL; + reg = RegionAbove( reg ); + } + return reg; +} + +static ActiveRegion *TopRightRegion( ActiveRegion *reg ) +{ + GLUvertex *dst = reg->eUp->Dst; + + /* Find the region above the uppermost edge with the same destination */ + do { + reg = RegionAbove( reg ); + } while( reg->eUp->Dst == dst ); + return reg; +} + +static ActiveRegion *AddRegionBelow( GLUtesselator *tess, + ActiveRegion *regAbove, + GLUhalfEdge *eNewUp ) +/* + * Add a new active region to the sweep line, *somewhere* below "regAbove" + * (according to where the new edge belongs in the sweep-line dictionary). + * The upper edge of the new region will be "eNewUp". + * Winding number and "inside" flag are not updated. + */ +{ + ActiveRegion *regNew = (ActiveRegion *)memAlloc( sizeof( ActiveRegion )); + if (regNew == NULL) longjmp(tess->env,1); + + regNew->eUp = eNewUp; + /* __gl_dictListInsertBefore */ + regNew->nodeUp = dictInsertBefore( tess->dict, regAbove->nodeUp, regNew ); + if (regNew->nodeUp == NULL) longjmp(tess->env,1); + regNew->fixUpperEdge = FALSE; + regNew->sentinel = FALSE; + regNew->dirty = FALSE; + + eNewUp->activeRegion = regNew; + return regNew; +} + +static GLboolean IsWindingInside( GLUtesselator *tess, int n ) +{ + switch( tess->windingRule ) { + case GLU_TESS_WINDING_ODD: + return (n & 1); + case GLU_TESS_WINDING_NONZERO: + return (n != 0); + case GLU_TESS_WINDING_POSITIVE: + return (n > 0); + case GLU_TESS_WINDING_NEGATIVE: + return (n < 0); + case GLU_TESS_WINDING_ABS_GEQ_TWO: + return (n >= 2) || (n <= -2); + } + /*LINTED*/ + assert( FALSE ); + /*NOTREACHED*/ + return GL_FALSE; /* avoid compiler complaints */ +} + + +static void ComputeWinding( GLUtesselator *tess, ActiveRegion *reg ) +{ + reg->windingNumber = RegionAbove(reg)->windingNumber + reg->eUp->winding; + reg->inside = IsWindingInside( tess, reg->windingNumber ); +} + + +static void FinishRegion( GLUtesselator *tess, ActiveRegion *reg ) +/* + * Delete a region from the sweep line. This happens when the upper + * and lower chains of a region meet (at a vertex on the sweep line). + * The "inside" flag is copied to the appropriate mesh face (we could + * not do this before -- since the structure of the mesh is always + * changing, this face may not have even existed until now). + */ +{ + GLUhalfEdge *e = reg->eUp; + GLUface *f = e->Lface; + + f->inside = reg->inside; + f->anEdge = e; /* optimization for __gl_meshTessellateMonoRegion() */ + DeleteRegion( tess, reg ); +} + + +static GLUhalfEdge *FinishLeftRegions( GLUtesselator *tess, + ActiveRegion *regFirst, ActiveRegion *regLast ) +/* + * We are given a vertex with one or more left-going edges. All affected + * edges should be in the edge dictionary. Starting at regFirst->eUp, + * we walk down deleting all regions where both edges have the same + * origin vOrg. At the same time we copy the "inside" flag from the + * active region to the face, since at this point each face will belong + * to at most one region (this was not necessarily true until this point + * in the sweep). The walk stops at the region above regLast; if regLast + * is NULL we walk as far as possible. At the same time we relink the + * mesh if necessary, so that the ordering of edges around vOrg is the + * same as in the dictionary. + */ +{ + ActiveRegion *reg, *regPrev; + GLUhalfEdge *e, *ePrev; + + regPrev = regFirst; + ePrev = regFirst->eUp; + while( regPrev != regLast ) { + regPrev->fixUpperEdge = FALSE; /* placement was OK */ + reg = RegionBelow( regPrev ); + e = reg->eUp; + if( e->Org != ePrev->Org ) { + if( ! reg->fixUpperEdge ) { + /* Remove the last left-going edge. Even though there are no further + * edges in the dictionary with this origin, there may be further + * such edges in the mesh (if we are adding left edges to a vertex + * that has already been processed). Thus it is important to call + * FinishRegion rather than just DeleteRegion. + */ + FinishRegion( tess, regPrev ); + break; + } + /* If the edge below was a temporary edge introduced by + * ConnectRightVertex, now is the time to fix it. + */ + e = __gl_meshConnect( ePrev->Lprev, e->Sym ); + if (e == NULL) longjmp(tess->env,1); + if ( !FixUpperEdge( reg, e ) ) longjmp(tess->env,1); + } + + /* Relink edges so that ePrev->Onext == e */ + if( ePrev->Onext != e ) { + if ( !__gl_meshSplice( e->Oprev, e ) ) longjmp(tess->env,1); + if ( !__gl_meshSplice( ePrev, e ) ) longjmp(tess->env,1); + } + FinishRegion( tess, regPrev ); /* may change reg->eUp */ + ePrev = reg->eUp; + regPrev = reg; + } + return ePrev; +} + + +static void AddRightEdges( GLUtesselator *tess, ActiveRegion *regUp, + GLUhalfEdge *eFirst, GLUhalfEdge *eLast, GLUhalfEdge *eTopLeft, + GLboolean cleanUp ) +/* + * Purpose: insert right-going edges into the edge dictionary, and update + * winding numbers and mesh connectivity appropriately. All right-going + * edges share a common origin vOrg. Edges are inserted CCW starting at + * eFirst; the last edge inserted is eLast->Oprev. If vOrg has any + * left-going edges already processed, then eTopLeft must be the edge + * such that an imaginary upward vertical segment from vOrg would be + * contained between eTopLeft->Oprev and eTopLeft; otherwise eTopLeft + * should be NULL. + */ +{ + ActiveRegion *reg, *regPrev; + GLUhalfEdge *e, *ePrev; + int firstTime = TRUE; + + /* Insert the new right-going edges in the dictionary */ + e = eFirst; + do { + assert( VertLeq( e->Org, e->Dst )); + AddRegionBelow( tess, regUp, e->Sym ); + e = e->Onext; + } while ( e != eLast ); + + /* Walk *all* right-going edges from e->Org, in the dictionary order, + * updating the winding numbers of each region, and re-linking the mesh + * edges to match the dictionary ordering (if necessary). + */ + if( eTopLeft == NULL ) { + eTopLeft = RegionBelow( regUp )->eUp->Rprev; + } + regPrev = regUp; + ePrev = eTopLeft; + for( ;; ) { + reg = RegionBelow( regPrev ); + e = reg->eUp->Sym; + if( e->Org != ePrev->Org ) break; + + if( e->Onext != ePrev ) { + /* Unlink e from its current position, and relink below ePrev */ + if ( !__gl_meshSplice( e->Oprev, e ) ) longjmp(tess->env,1); + if ( !__gl_meshSplice( ePrev->Oprev, e ) ) longjmp(tess->env,1); + } + /* Compute the winding number and "inside" flag for the new regions */ + reg->windingNumber = regPrev->windingNumber - e->winding; + reg->inside = IsWindingInside( tess, reg->windingNumber ); + + /* Check for two outgoing edges with same slope -- process these + * before any intersection tests (see example in __gl_computeInterior). + */ + regPrev->dirty = TRUE; + if( ! firstTime && CheckForRightSplice( tess, regPrev )) { + AddWinding( e, ePrev ); + DeleteRegion( tess, regPrev ); + if ( !__gl_meshDelete( ePrev ) ) longjmp(tess->env,1); + } + firstTime = FALSE; + regPrev = reg; + ePrev = e; + } + regPrev->dirty = TRUE; + assert( regPrev->windingNumber - e->winding == reg->windingNumber ); + + if( cleanUp ) { + /* Check for intersections between newly adjacent edges. */ + WalkDirtyRegions( tess, regPrev ); + } +} + + +static void CallCombine( GLUtesselator *tess, GLUvertex *isect, + void *data[4], GLfloat weights[4], int needed ) +{ + GLdouble coords[3]; + + /* Copy coord data in case the callback changes it. */ + coords[0] = isect->coords[0]; + coords[1] = isect->coords[1]; + coords[2] = isect->coords[2]; + + isect->data = NULL; + CALL_COMBINE_OR_COMBINE_DATA( coords, data, weights, &isect->data ); + if( isect->data == NULL ) { + if( ! needed ) { + isect->data = data[0]; + } else if( ! tess->fatalError ) { + /* The only way fatal error is when two edges are found to intersect, + * but the user has not provided the callback necessary to handle + * generated intersection points. + */ + CALL_ERROR_OR_ERROR_DATA( GLU_TESS_NEED_COMBINE_CALLBACK ); + tess->fatalError = TRUE; + } + } +} + +static void SpliceMergeVertices( GLUtesselator *tess, GLUhalfEdge *e1, + GLUhalfEdge *e2 ) +/* + * Two vertices with idential coordinates are combined into one. + * e1->Org is kept, while e2->Org is discarded. + */ +{ + void *data[4] = { NULL, NULL, NULL, NULL }; + GLfloat weights[4] = { 0.5, 0.5, 0.0, 0.0 }; + + data[0] = e1->Org->data; + data[1] = e2->Org->data; + CallCombine( tess, e1->Org, data, weights, FALSE ); + if ( !__gl_meshSplice( e1, e2 ) ) longjmp(tess->env,1); +} + +static void VertexWeights( GLUvertex *isect, GLUvertex *org, GLUvertex *dst, + GLfloat *weights ) +/* + * Find some weights which describe how the intersection vertex is + * a linear combination of "org" and "dest". Each of the two edges + * which generated "isect" is allocated 50% of the weight; each edge + * splits the weight between its org and dst according to the + * relative distance to "isect". + */ +{ + GLdouble t1 = VertL1dist( org, isect ); + GLdouble t2 = VertL1dist( dst, isect ); + + weights[0] = 0.5 * t2 / (t1 + t2); + weights[1] = 0.5 * t1 / (t1 + t2); + isect->coords[0] += weights[0]*org->coords[0] + weights[1]*dst->coords[0]; + isect->coords[1] += weights[0]*org->coords[1] + weights[1]*dst->coords[1]; + isect->coords[2] += weights[0]*org->coords[2] + weights[1]*dst->coords[2]; +} + + +static void GetIntersectData( GLUtesselator *tess, GLUvertex *isect, + GLUvertex *orgUp, GLUvertex *dstUp, + GLUvertex *orgLo, GLUvertex *dstLo ) +/* + * We've computed a new intersection point, now we need a "data" pointer + * from the user so that we can refer to this new vertex in the + * rendering callbacks. + */ +{ + void *data[4]; + GLfloat weights[4]; + + data[0] = orgUp->data; + data[1] = dstUp->data; + data[2] = orgLo->data; + data[3] = dstLo->data; + + isect->coords[0] = isect->coords[1] = isect->coords[2] = 0; + VertexWeights( isect, orgUp, dstUp, &weights[0] ); + VertexWeights( isect, orgLo, dstLo, &weights[2] ); + + CallCombine( tess, isect, data, weights, TRUE ); +} + +static int CheckForRightSplice( GLUtesselator *tess, ActiveRegion *regUp ) +/* + * Check the upper and lower edge of "regUp", to make sure that the + * eUp->Org is above eLo, or eLo->Org is below eUp (depending on which + * origin is leftmost). + * + * The main purpose is to splice right-going edges with the same + * dest vertex and nearly identical slopes (ie. we can't distinguish + * the slopes numerically). However the splicing can also help us + * to recover from numerical errors. For example, suppose at one + * point we checked eUp and eLo, and decided that eUp->Org is barely + * above eLo. Then later, we split eLo into two edges (eg. from + * a splice operation like this one). This can change the result of + * our test so that now eUp->Org is incident to eLo, or barely below it. + * We must correct this condition to maintain the dictionary invariants. + * + * One possibility is to check these edges for intersection again + * (ie. CheckForIntersect). This is what we do if possible. However + * CheckForIntersect requires that tess->event lies between eUp and eLo, + * so that it has something to fall back on when the intersection + * calculation gives us an unusable answer. So, for those cases where + * we can't check for intersection, this routine fixes the problem + * by just splicing the offending vertex into the other edge. + * This is a guaranteed solution, no matter how degenerate things get. + * Basically this is a combinatorial solution to a numerical problem. + */ +{ + ActiveRegion *regLo = RegionBelow(regUp); + GLUhalfEdge *eUp = regUp->eUp; + GLUhalfEdge *eLo = regLo->eUp; + + if( VertLeq( eUp->Org, eLo->Org )) { + if( EdgeSign( eLo->Dst, eUp->Org, eLo->Org ) > 0 ) return FALSE; + + /* eUp->Org appears to be below eLo */ + if( ! VertEq( eUp->Org, eLo->Org )) { + /* Splice eUp->Org into eLo */ + if ( __gl_meshSplitEdge( eLo->Sym ) == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eUp, eLo->Oprev ) ) longjmp(tess->env,1); + regUp->dirty = regLo->dirty = TRUE; + + } else if( eUp->Org != eLo->Org ) { + /* merge the two vertices, discarding eUp->Org */ + pqDelete( tess->pq, eUp->Org->pqHandle ); /* __gl_pqSortDelete */ + SpliceMergeVertices( tess, eLo->Oprev, eUp ); + } + } else { + if( EdgeSign( eUp->Dst, eLo->Org, eUp->Org ) < 0 ) return FALSE; + + /* eLo->Org appears to be above eUp, so splice eLo->Org into eUp */ + RegionAbove(regUp)->dirty = regUp->dirty = TRUE; + if (__gl_meshSplitEdge( eUp->Sym ) == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eLo->Oprev, eUp ) ) longjmp(tess->env,1); + } + return TRUE; +} + +static int CheckForLeftSplice( GLUtesselator *tess, ActiveRegion *regUp ) +/* + * Check the upper and lower edge of "regUp", to make sure that the + * eUp->Dst is above eLo, or eLo->Dst is below eUp (depending on which + * destination is rightmost). + * + * Theoretically, this should always be true. However, splitting an edge + * into two pieces can change the results of previous tests. For example, + * suppose at one point we checked eUp and eLo, and decided that eUp->Dst + * is barely above eLo. Then later, we split eLo into two edges (eg. from + * a splice operation like this one). This can change the result of + * the test so that now eUp->Dst is incident to eLo, or barely below it. + * We must correct this condition to maintain the dictionary invariants + * (otherwise new edges might get inserted in the wrong place in the + * dictionary, and bad stuff will happen). + * + * We fix the problem by just splicing the offending vertex into the + * other edge. + */ +{ + ActiveRegion *regLo = RegionBelow(regUp); + GLUhalfEdge *eUp = regUp->eUp; + GLUhalfEdge *eLo = regLo->eUp; + GLUhalfEdge *e; + + assert( ! VertEq( eUp->Dst, eLo->Dst )); + + if( VertLeq( eUp->Dst, eLo->Dst )) { + if( EdgeSign( eUp->Dst, eLo->Dst, eUp->Org ) < 0 ) return FALSE; + + /* eLo->Dst is above eUp, so splice eLo->Dst into eUp */ + RegionAbove(regUp)->dirty = regUp->dirty = TRUE; + e = __gl_meshSplitEdge( eUp ); + if (e == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eLo->Sym, e ) ) longjmp(tess->env,1); + e->Lface->inside = regUp->inside; + } else { + if( EdgeSign( eLo->Dst, eUp->Dst, eLo->Org ) > 0 ) return FALSE; + + /* eUp->Dst is below eLo, so splice eUp->Dst into eLo */ + regUp->dirty = regLo->dirty = TRUE; + e = __gl_meshSplitEdge( eLo ); + if (e == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eUp->Lnext, eLo->Sym ) ) longjmp(tess->env,1); + e->Rface->inside = regUp->inside; + } + return TRUE; +} + + +static int CheckForIntersect( GLUtesselator *tess, ActiveRegion *regUp ) +/* + * Check the upper and lower edges of the given region to see if + * they intersect. If so, create the intersection and add it + * to the data structures. + * + * Returns TRUE if adding the new intersection resulted in a recursive + * call to AddRightEdges(); in this case all "dirty" regions have been + * checked for intersections, and possibly regUp has been deleted. + */ +{ + ActiveRegion *regLo = RegionBelow(regUp); + GLUhalfEdge *eUp = regUp->eUp; + GLUhalfEdge *eLo = regLo->eUp; + GLUvertex *orgUp = eUp->Org; + GLUvertex *orgLo = eLo->Org; + GLUvertex *dstUp = eUp->Dst; + GLUvertex *dstLo = eLo->Dst; + GLdouble tMinUp, tMaxLo; + GLUvertex isect, *orgMin; + GLUhalfEdge *e; + + assert( ! VertEq( dstLo, dstUp )); + assert( EdgeSign( dstUp, tess->event, orgUp ) <= 0 ); + assert( EdgeSign( dstLo, tess->event, orgLo ) >= 0 ); + assert( orgUp != tess->event && orgLo != tess->event ); + assert( ! regUp->fixUpperEdge && ! regLo->fixUpperEdge ); + + if( orgUp == orgLo ) return FALSE; /* right endpoints are the same */ + + tMinUp = MIN( orgUp->t, dstUp->t ); + tMaxLo = MAX( orgLo->t, dstLo->t ); + if( tMinUp > tMaxLo ) return FALSE; /* t ranges do not overlap */ + + if( VertLeq( orgUp, orgLo )) { + if( EdgeSign( dstLo, orgUp, orgLo ) > 0 ) return FALSE; + } else { + if( EdgeSign( dstUp, orgLo, orgUp ) < 0 ) return FALSE; + } + + /* At this point the edges intersect, at least marginally */ + DebugEvent( tess ); + + __gl_edgeIntersect( dstUp, orgUp, dstLo, orgLo, &isect ); + /* The following properties are guaranteed: */ + assert( MIN( orgUp->t, dstUp->t ) <= isect.t ); + assert( isect.t <= MAX( orgLo->t, dstLo->t )); + assert( MIN( dstLo->s, dstUp->s ) <= isect.s ); + assert( isect.s <= MAX( orgLo->s, orgUp->s )); + + if( VertLeq( &isect, tess->event )) { + /* The intersection point lies slightly to the left of the sweep line, + * so move it until it''s slightly to the right of the sweep line. + * (If we had perfect numerical precision, this would never happen + * in the first place). The easiest and safest thing to do is + * replace the intersection by tess->event. + */ + isect.s = tess->event->s; + isect.t = tess->event->t; + } + /* Similarly, if the computed intersection lies to the right of the + * rightmost origin (which should rarely happen), it can cause + * unbelievable inefficiency on sufficiently degenerate inputs. + * (If you have the test program, try running test54.d with the + * "X zoom" option turned on). + */ + orgMin = VertLeq( orgUp, orgLo ) ? orgUp : orgLo; + if( VertLeq( orgMin, &isect )) { + isect.s = orgMin->s; + isect.t = orgMin->t; + } + + if( VertEq( &isect, orgUp ) || VertEq( &isect, orgLo )) { + /* Easy case -- intersection at one of the right endpoints */ + (void) CheckForRightSplice( tess, regUp ); + return FALSE; + } + + if( (! VertEq( dstUp, tess->event ) + && EdgeSign( dstUp, tess->event, &isect ) >= 0) + || (! VertEq( dstLo, tess->event ) + && EdgeSign( dstLo, tess->event, &isect ) <= 0 )) + { + /* Very unusual -- the new upper or lower edge would pass on the + * wrong side of the sweep event, or through it. This can happen + * due to very small numerical errors in the intersection calculation. + */ + if( dstLo == tess->event ) { + /* Splice dstLo into eUp, and process the new region(s) */ + if (__gl_meshSplitEdge( eUp->Sym ) == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eLo->Sym, eUp ) ) longjmp(tess->env,1); + regUp = TopLeftRegion( regUp ); + if (regUp == NULL) longjmp(tess->env,1); + eUp = RegionBelow(regUp)->eUp; + FinishLeftRegions( tess, RegionBelow(regUp), regLo ); + AddRightEdges( tess, regUp, eUp->Oprev, eUp, eUp, TRUE ); + return TRUE; + } + if( dstUp == tess->event ) { + /* Splice dstUp into eLo, and process the new region(s) */ + if (__gl_meshSplitEdge( eLo->Sym ) == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eUp->Lnext, eLo->Oprev ) ) longjmp(tess->env,1); + regLo = regUp; + regUp = TopRightRegion( regUp ); + e = RegionBelow(regUp)->eUp->Rprev; + regLo->eUp = eLo->Oprev; + eLo = FinishLeftRegions( tess, regLo, NULL ); + AddRightEdges( tess, regUp, eLo->Onext, eUp->Rprev, e, TRUE ); + return TRUE; + } + /* Special case: called from ConnectRightVertex. If either + * edge passes on the wrong side of tess->event, split it + * (and wait for ConnectRightVertex to splice it appropriately). + */ + if( EdgeSign( dstUp, tess->event, &isect ) >= 0 ) { + RegionAbove(regUp)->dirty = regUp->dirty = TRUE; + if (__gl_meshSplitEdge( eUp->Sym ) == NULL) longjmp(tess->env,1); + eUp->Org->s = tess->event->s; + eUp->Org->t = tess->event->t; + } + if( EdgeSign( dstLo, tess->event, &isect ) <= 0 ) { + regUp->dirty = regLo->dirty = TRUE; + if (__gl_meshSplitEdge( eLo->Sym ) == NULL) longjmp(tess->env,1); + eLo->Org->s = tess->event->s; + eLo->Org->t = tess->event->t; + } + /* leave the rest for ConnectRightVertex */ + return FALSE; + } + + /* General case -- split both edges, splice into new vertex. + * When we do the splice operation, the order of the arguments is + * arbitrary as far as correctness goes. However, when the operation + * creates a new face, the work done is proportional to the size of + * the new face. We expect the faces in the processed part of + * the mesh (ie. eUp->Lface) to be smaller than the faces in the + * unprocessed original contours (which will be eLo->Oprev->Lface). + */ + if (__gl_meshSplitEdge( eUp->Sym ) == NULL) longjmp(tess->env,1); + if (__gl_meshSplitEdge( eLo->Sym ) == NULL) longjmp(tess->env,1); + if ( !__gl_meshSplice( eLo->Oprev, eUp ) ) longjmp(tess->env,1); + eUp->Org->s = isect.s; + eUp->Org->t = isect.t; + eUp->Org->pqHandle = pqInsert( tess->pq, eUp->Org ); /* __gl_pqSortInsert */ + if (eUp->Org->pqHandle == LONG_MAX) { + pqDeletePriorityQ(tess->pq); /* __gl_pqSortDeletePriorityQ */ + tess->pq = NULL; + longjmp(tess->env,1); + } + GetIntersectData( tess, eUp->Org, orgUp, dstUp, orgLo, dstLo ); + RegionAbove(regUp)->dirty = regUp->dirty = regLo->dirty = TRUE; + return FALSE; +} + +static void WalkDirtyRegions( GLUtesselator *tess, ActiveRegion *regUp ) +/* + * When the upper or lower edge of any region changes, the region is + * marked "dirty". This routine walks through all the dirty regions + * and makes sure that the dictionary invariants are satisfied + * (see the comments at the beginning of this file). Of course + * new dirty regions can be created as we make changes to restore + * the invariants. + */ +{ + ActiveRegion *regLo = RegionBelow(regUp); + GLUhalfEdge *eUp, *eLo; + + for( ;; ) { + /* Find the lowest dirty region (we walk from the bottom up). */ + while( regLo->dirty ) { + regUp = regLo; + regLo = RegionBelow(regLo); + } + if( ! regUp->dirty ) { + regLo = regUp; + regUp = RegionAbove( regUp ); + if( regUp == NULL || ! regUp->dirty ) { + /* We've walked all the dirty regions */ + return; + } + } + regUp->dirty = FALSE; + eUp = regUp->eUp; + eLo = regLo->eUp; + + if( eUp->Dst != eLo->Dst ) { + /* Check that the edge ordering is obeyed at the Dst vertices. */ + if( CheckForLeftSplice( tess, regUp )) { + + /* If the upper or lower edge was marked fixUpperEdge, then + * we no longer need it (since these edges are needed only for + * vertices which otherwise have no right-going edges). + */ + if( regLo->fixUpperEdge ) { + DeleteRegion( tess, regLo ); + if ( !__gl_meshDelete( eLo ) ) longjmp(tess->env,1); + regLo = RegionBelow( regUp ); + eLo = regLo->eUp; + } else if( regUp->fixUpperEdge ) { + DeleteRegion( tess, regUp ); + if ( !__gl_meshDelete( eUp ) ) longjmp(tess->env,1); + regUp = RegionAbove( regLo ); + eUp = regUp->eUp; + } + } + } + if( eUp->Org != eLo->Org ) { + if( eUp->Dst != eLo->Dst + && ! regUp->fixUpperEdge && ! regLo->fixUpperEdge + && (eUp->Dst == tess->event || eLo->Dst == tess->event) ) + { + /* When all else fails in CheckForIntersect(), it uses tess->event + * as the intersection location. To make this possible, it requires + * that tess->event lie between the upper and lower edges, and also + * that neither of these is marked fixUpperEdge (since in the worst + * case it might splice one of these edges into tess->event, and + * violate the invariant that fixable edges are the only right-going + * edge from their associated vertex). + */ + if( CheckForIntersect( tess, regUp )) { + /* WalkDirtyRegions() was called recursively; we're done */ + return; + } + } else { + /* Even though we can't use CheckForIntersect(), the Org vertices + * may violate the dictionary edge ordering. Check and correct this. + */ + (void) CheckForRightSplice( tess, regUp ); + } + } + if( eUp->Org == eLo->Org && eUp->Dst == eLo->Dst ) { + /* A degenerate loop consisting of only two edges -- delete it. */ + AddWinding( eLo, eUp ); + DeleteRegion( tess, regUp ); + if ( !__gl_meshDelete( eUp ) ) longjmp(tess->env,1); + regUp = RegionAbove( regLo ); + } + } +} + + +static void ConnectRightVertex( GLUtesselator *tess, ActiveRegion *regUp, + GLUhalfEdge *eBottomLeft ) +/* + * Purpose: connect a "right" vertex vEvent (one where all edges go left) + * to the unprocessed portion of the mesh. Since there are no right-going + * edges, two regions (one above vEvent and one below) are being merged + * into one. "regUp" is the upper of these two regions. + * + * There are two reasons for doing this (adding a right-going edge): + * - if the two regions being merged are "inside", we must add an edge + * to keep them separated (the combined region would not be monotone). + * - in any case, we must leave some record of vEvent in the dictionary, + * so that we can merge vEvent with features that we have not seen yet. + * For example, maybe there is a vertical edge which passes just to + * the right of vEvent; we would like to splice vEvent into this edge. + * + * However, we don't want to connect vEvent to just any vertex. We don''t + * want the new edge to cross any other edges; otherwise we will create + * intersection vertices even when the input data had no self-intersections. + * (This is a bad thing; if the user's input data has no intersections, + * we don't want to generate any false intersections ourselves.) + * + * Our eventual goal is to connect vEvent to the leftmost unprocessed + * vertex of the combined region (the union of regUp and regLo). + * But because of unseen vertices with all right-going edges, and also + * new vertices which may be created by edge intersections, we don''t + * know where that leftmost unprocessed vertex is. In the meantime, we + * connect vEvent to the closest vertex of either chain, and mark the region + * as "fixUpperEdge". This flag says to delete and reconnect this edge + * to the next processed vertex on the boundary of the combined region. + * Quite possibly the vertex we connected to will turn out to be the + * closest one, in which case we won''t need to make any changes. + */ +{ + GLUhalfEdge *eNew; + GLUhalfEdge *eTopLeft = eBottomLeft->Onext; + ActiveRegion *regLo = RegionBelow(regUp); + GLUhalfEdge *eUp = regUp->eUp; + GLUhalfEdge *eLo = regLo->eUp; + int degenerate = FALSE; + + if( eUp->Dst != eLo->Dst ) { + (void) CheckForIntersect( tess, regUp ); + } + + /* Possible new degeneracies: upper or lower edge of regUp may pass + * through vEvent, or may coincide with new intersection vertex + */ + if( VertEq( eUp->Org, tess->event )) { + if ( !__gl_meshSplice( eTopLeft->Oprev, eUp ) ) longjmp(tess->env,1); + regUp = TopLeftRegion( regUp ); + if (regUp == NULL) longjmp(tess->env,1); + eTopLeft = RegionBelow( regUp )->eUp; + FinishLeftRegions( tess, RegionBelow(regUp), regLo ); + degenerate = TRUE; + } + if( VertEq( eLo->Org, tess->event )) { + if ( !__gl_meshSplice( eBottomLeft, eLo->Oprev ) ) longjmp(tess->env,1); + eBottomLeft = FinishLeftRegions( tess, regLo, NULL ); + degenerate = TRUE; + } + if( degenerate ) { + AddRightEdges( tess, regUp, eBottomLeft->Onext, eTopLeft, eTopLeft, TRUE ); + return; + } + + /* Non-degenerate situation -- need to add a temporary, fixable edge. + * Connect to the closer of eLo->Org, eUp->Org. + */ + if( VertLeq( eLo->Org, eUp->Org )) { + eNew = eLo->Oprev; + } else { + eNew = eUp; + } + eNew = __gl_meshConnect( eBottomLeft->Lprev, eNew ); + if (eNew == NULL) longjmp(tess->env,1); + + /* Prevent cleanup, otherwise eNew might disappear before we've even + * had a chance to mark it as a temporary edge. + */ + AddRightEdges( tess, regUp, eNew, eNew->Onext, eNew->Onext, FALSE ); + eNew->Sym->activeRegion->fixUpperEdge = TRUE; + WalkDirtyRegions( tess, regUp ); +} + +/* Because vertices at exactly the same location are merged together + * before we process the sweep event, some degenerate cases can't occur. + * However if someone eventually makes the modifications required to + * merge features which are close together, the cases below marked + * TOLERANCE_NONZERO will be useful. They were debugged before the + * code to merge identical vertices in the main loop was added. + */ +#define TOLERANCE_NONZERO FALSE + +static void ConnectLeftDegenerate( GLUtesselator *tess, + ActiveRegion *regUp, GLUvertex *vEvent ) +/* + * The event vertex lies exacty on an already-processed edge or vertex. + * Adding the new vertex involves splicing it into the already-processed + * part of the mesh. + */ +{ + GLUhalfEdge *e, *eTopLeft, *eTopRight, *eLast; + ActiveRegion *reg; + + e = regUp->eUp; + if( VertEq( e->Org, vEvent )) { + /* e->Org is an unprocessed vertex - just combine them, and wait + * for e->Org to be pulled from the queue + */ + assert( TOLERANCE_NONZERO ); + SpliceMergeVertices( tess, e, vEvent->anEdge ); + return; + } + + if( ! VertEq( e->Dst, vEvent )) { + /* General case -- splice vEvent into edge e which passes through it */ + if (__gl_meshSplitEdge( e->Sym ) == NULL) longjmp(tess->env,1); + if( regUp->fixUpperEdge ) { + /* This edge was fixable -- delete unused portion of original edge */ + if ( !__gl_meshDelete( e->Onext ) ) longjmp(tess->env,1); + regUp->fixUpperEdge = FALSE; + } + if ( !__gl_meshSplice( vEvent->anEdge, e ) ) longjmp(tess->env,1); + SweepEvent( tess, vEvent ); /* recurse */ + return; + } + + /* vEvent coincides with e->Dst, which has already been processed. + * Splice in the additional right-going edges. + */ + assert( TOLERANCE_NONZERO ); + regUp = TopRightRegion( regUp ); + reg = RegionBelow( regUp ); + eTopRight = reg->eUp->Sym; + eTopLeft = eLast = eTopRight->Onext; + if( reg->fixUpperEdge ) { + /* Here e->Dst has only a single fixable edge going right. + * We can delete it since now we have some real right-going edges. + */ + assert( eTopLeft != eTopRight ); /* there are some left edges too */ + DeleteRegion( tess, reg ); + if ( !__gl_meshDelete( eTopRight ) ) longjmp(tess->env,1); + eTopRight = eTopLeft->Oprev; + } + if ( !__gl_meshSplice( vEvent->anEdge, eTopRight ) ) longjmp(tess->env,1); + if( ! EdgeGoesLeft( eTopLeft )) { + /* e->Dst had no left-going edges -- indicate this to AddRightEdges() */ + eTopLeft = NULL; + } + AddRightEdges( tess, regUp, eTopRight->Onext, eLast, eTopLeft, TRUE ); +} + + +static void ConnectLeftVertex( GLUtesselator *tess, GLUvertex *vEvent ) +/* + * Purpose: connect a "left" vertex (one where both edges go right) + * to the processed portion of the mesh. Let R be the active region + * containing vEvent, and let U and L be the upper and lower edge + * chains of R. There are two possibilities: + * + * - the normal case: split R into two regions, by connecting vEvent to + * the rightmost vertex of U or L lying to the left of the sweep line + * + * - the degenerate case: if vEvent is close enough to U or L, we + * merge vEvent into that edge chain. The subcases are: + * - merging with the rightmost vertex of U or L + * - merging with the active edge of U or L + * - merging with an already-processed portion of U or L + */ +{ + ActiveRegion *regUp, *regLo, *reg; + GLUhalfEdge *eUp, *eLo, *eNew; + ActiveRegion tmp; + + /* assert( vEvent->anEdge->Onext->Onext == vEvent->anEdge ); */ + + /* Get a pointer to the active region containing vEvent */ + tmp.eUp = vEvent->anEdge->Sym; + /* __GL_DICTLISTKEY */ /* __gl_dictListSearch */ + regUp = (ActiveRegion *)dictKey( dictSearch( tess->dict, &tmp )); + regLo = RegionBelow( regUp ); + eUp = regUp->eUp; + eLo = regLo->eUp; + + /* Try merging with U or L first */ + if( EdgeSign( eUp->Dst, vEvent, eUp->Org ) == 0 ) { + ConnectLeftDegenerate( tess, regUp, vEvent ); + return; + } + + /* Connect vEvent to rightmost processed vertex of either chain. + * e->Dst is the vertex that we will connect to vEvent. + */ + reg = VertLeq( eLo->Dst, eUp->Dst ) ? regUp : regLo; + + if( regUp->inside || reg->fixUpperEdge) { + if( reg == regUp ) { + eNew = __gl_meshConnect( vEvent->anEdge->Sym, eUp->Lnext ); + if (eNew == NULL) longjmp(tess->env,1); + } else { + GLUhalfEdge *tempHalfEdge= __gl_meshConnect( eLo->Dnext, vEvent->anEdge); + if (tempHalfEdge == NULL) longjmp(tess->env,1); + + eNew = tempHalfEdge->Sym; + } + if( reg->fixUpperEdge ) { + if ( !FixUpperEdge( reg, eNew ) ) longjmp(tess->env,1); + } else { + ComputeWinding( tess, AddRegionBelow( tess, regUp, eNew )); + } + SweepEvent( tess, vEvent ); + } else { + /* The new vertex is in a region which does not belong to the polygon. + * We don''t need to connect this vertex to the rest of the mesh. + */ + AddRightEdges( tess, regUp, vEvent->anEdge, vEvent->anEdge, NULL, TRUE ); + } +} + + +static void SweepEvent( GLUtesselator *tess, GLUvertex *vEvent ) +/* + * Does everything necessary when the sweep line crosses a vertex. + * Updates the mesh and the edge dictionary. + */ +{ + ActiveRegion *regUp, *reg; + GLUhalfEdge *e, *eTopLeft, *eBottomLeft; + + tess->event = vEvent; /* for access in EdgeLeq() */ + DebugEvent( tess ); + + /* Check if this vertex is the right endpoint of an edge that is + * already in the dictionary. In this case we don't need to waste + * time searching for the location to insert new edges. + */ + e = vEvent->anEdge; + while( e->activeRegion == NULL ) { + e = e->Onext; + if( e == vEvent->anEdge ) { + /* All edges go right -- not incident to any processed edges */ + ConnectLeftVertex( tess, vEvent ); + return; + } + } + + /* Processing consists of two phases: first we "finish" all the + * active regions where both the upper and lower edges terminate + * at vEvent (ie. vEvent is closing off these regions). + * We mark these faces "inside" or "outside" the polygon according + * to their winding number, and delete the edges from the dictionary. + * This takes care of all the left-going edges from vEvent. + */ + regUp = TopLeftRegion( e->activeRegion ); + if (regUp == NULL) longjmp(tess->env,1); + reg = RegionBelow( regUp ); + eTopLeft = reg->eUp; + eBottomLeft = FinishLeftRegions( tess, reg, NULL ); + + /* Next we process all the right-going edges from vEvent. This + * involves adding the edges to the dictionary, and creating the + * associated "active regions" which record information about the + * regions between adjacent dictionary edges. + */ + if( eBottomLeft->Onext == eTopLeft ) { + /* No right-going edges -- add a temporary "fixable" edge */ + ConnectRightVertex( tess, regUp, eBottomLeft ); + } else { + AddRightEdges( tess, regUp, eBottomLeft->Onext, eTopLeft, eTopLeft, TRUE ); + } +} + + +/* Make the sentinel coordinates big enough that they will never be + * merged with real input features. (Even with the largest possible + * input contour and the maximum tolerance of 1.0, no merging will be + * done with coordinates larger than 3 * GLU_TESS_MAX_COORD). + */ +#define SENTINEL_COORD (4 * GLU_TESS_MAX_COORD) + +static void AddSentinel( GLUtesselator *tess, GLdouble t ) +/* + * We add two sentinel edges above and below all other edges, + * to avoid special cases at the top and bottom. + */ +{ + GLUhalfEdge *e; + ActiveRegion *reg = (ActiveRegion *)memAlloc( sizeof( ActiveRegion )); + if (reg == NULL) longjmp(tess->env,1); + + e = __gl_meshMakeEdge( tess->mesh ); + if (e == NULL) longjmp(tess->env,1); + + e->Org->s = SENTINEL_COORD; + e->Org->t = t; + e->Dst->s = -SENTINEL_COORD; + e->Dst->t = t; + tess->event = e->Dst; /* initialize it */ + + reg->eUp = e; + reg->windingNumber = 0; + reg->inside = FALSE; + reg->fixUpperEdge = FALSE; + reg->sentinel = TRUE; + reg->dirty = FALSE; + reg->nodeUp = dictInsert( tess->dict, reg ); /* __gl_dictListInsertBefore */ + if (reg->nodeUp == NULL) longjmp(tess->env,1); +} + + +static void InitEdgeDict( GLUtesselator *tess ) +/* + * We maintain an ordering of edge intersections with the sweep line. + * This order is maintained in a dynamic dictionary. + */ +{ + /* __gl_dictListNewDict */ + tess->dict = dictNewDict( tess, (int (*)(void *, DictKey, DictKey)) EdgeLeq ); + if (tess->dict == NULL) longjmp(tess->env,1); + + AddSentinel( tess, -SENTINEL_COORD ); + AddSentinel( tess, SENTINEL_COORD ); +} + + +static void DoneEdgeDict( GLUtesselator *tess ) +{ + ActiveRegion *reg; +#ifndef NDEBUG + int fixedEdges = 0; +#endif + + /* __GL_DICTLISTKEY */ /* __GL_DICTLISTMIN */ + while( (reg = (ActiveRegion *)dictKey( dictMin( tess->dict ))) != NULL ) { + /* + * At the end of all processing, the dictionary should contain + * only the two sentinel edges, plus at most one "fixable" edge + * created by ConnectRightVertex(). + */ + if( ! reg->sentinel ) { + assert( reg->fixUpperEdge ); + assert( ++fixedEdges == 1 ); + } + assert( reg->windingNumber == 0 ); + DeleteRegion( tess, reg ); +/* __gl_meshDelete( reg->eUp );*/ + } + dictDeleteDict( tess->dict ); /* __gl_dictListDeleteDict */ +} + + +static void RemoveDegenerateEdges( GLUtesselator *tess ) +/* + * Remove zero-length edges, and contours with fewer than 3 vertices. + */ +{ + GLUhalfEdge *e, *eNext, *eLnext; + GLUhalfEdge *eHead = &tess->mesh->eHead; + + /*LINTED*/ + for( e = eHead->next; e != eHead; e = eNext ) { + eNext = e->next; + eLnext = e->Lnext; + + if( VertEq( e->Org, e->Dst ) && e->Lnext->Lnext != e ) { + /* Zero-length edge, contour has at least 3 edges */ + + SpliceMergeVertices( tess, eLnext, e ); /* deletes e->Org */ + if ( !__gl_meshDelete( e ) ) longjmp(tess->env,1); /* e is a self-loop */ + e = eLnext; + eLnext = e->Lnext; + } + if( eLnext->Lnext == e ) { + /* Degenerate contour (one or two edges) */ + + if( eLnext != e ) { + if( eLnext == eNext || eLnext == eNext->Sym ) { eNext = eNext->next; } + if ( !__gl_meshDelete( eLnext ) ) longjmp(tess->env,1); + } + if( e == eNext || e == eNext->Sym ) { eNext = eNext->next; } + if ( !__gl_meshDelete( e ) ) longjmp(tess->env,1); + } + } +} + +static int InitPriorityQ( GLUtesselator *tess ) +/* + * Insert all vertices into the priority queue which determines the + * order in which vertices cross the sweep line. + */ +{ + PriorityQ *pq; + GLUvertex *v, *vHead; + + /* __gl_pqSortNewPriorityQ */ + pq = tess->pq = pqNewPriorityQ( (int (*)(PQkey, PQkey)) __gl_vertLeq ); + if (pq == NULL) return 0; + + vHead = &tess->mesh->vHead; + for( v = vHead->next; v != vHead; v = v->next ) { + v->pqHandle = pqInsert( pq, v ); /* __gl_pqSortInsert */ + if (v->pqHandle == LONG_MAX) break; + } + if (v != vHead || !pqInit( pq ) ) { /* __gl_pqSortInit */ + pqDeletePriorityQ(tess->pq); /* __gl_pqSortDeletePriorityQ */ + tess->pq = NULL; + return 0; + } + + return 1; +} + + +static void DonePriorityQ( GLUtesselator *tess ) +{ + pqDeletePriorityQ( tess->pq ); /* __gl_pqSortDeletePriorityQ */ +} + + +static int RemoveDegenerateFaces( GLUmesh *mesh ) +/* + * Delete any degenerate faces with only two edges. WalkDirtyRegions() + * will catch almost all of these, but it won't catch degenerate faces + * produced by splice operations on already-processed edges. + * The two places this can happen are in FinishLeftRegions(), when + * we splice in a "temporary" edge produced by ConnectRightVertex(), + * and in CheckForLeftSplice(), where we splice already-processed + * edges to ensure that our dictionary invariants are not violated + * by numerical errors. + * + * In both these cases it is *very* dangerous to delete the offending + * edge at the time, since one of the routines further up the stack + * will sometimes be keeping a pointer to that edge. + */ +{ + GLUface *f, *fNext; + GLUhalfEdge *e; + + /*LINTED*/ + for( f = mesh->fHead.next; f != &mesh->fHead; f = fNext ) { + fNext = f->next; + e = f->anEdge; + assert( e->Lnext != e ); + + if( e->Lnext->Lnext == e ) { + /* A face with only two edges */ + AddWinding( e->Onext, e ); + if ( !__gl_meshDelete( e ) ) return 0; + } + } + return 1; +} + +int __gl_computeInterior( GLUtesselator *tess ) +/* + * __gl_computeInterior( tess ) computes the planar arrangement specified + * by the given contours, and further subdivides this arrangement + * into regions. Each region is marked "inside" if it belongs + * to the polygon, according to the rule given by tess->windingRule. + * Each interior region is guaranteed be monotone. + */ +{ + GLUvertex *v, *vNext; + + tess->fatalError = FALSE; + + /* Each vertex defines an event for our sweep line. Start by inserting + * all the vertices in a priority queue. Events are processed in + * lexicographic order, ie. + * + * e1 < e2 iff e1.x < e2.x || (e1.x == e2.x && e1.y < e2.y) + */ + RemoveDegenerateEdges( tess ); + if ( !InitPriorityQ( tess ) ) return 0; /* if error */ + InitEdgeDict( tess ); + + /* __gl_pqSortExtractMin */ + while( (v = (GLUvertex *)pqExtractMin( tess->pq )) != NULL ) { + for( ;; ) { + vNext = (GLUvertex *)pqMinimum( tess->pq ); /* __gl_pqSortMinimum */ + if( vNext == NULL || ! VertEq( vNext, v )) break; + + /* Merge together all vertices at exactly the same location. + * This is more efficient than processing them one at a time, + * simplifies the code (see ConnectLeftDegenerate), and is also + * important for correct handling of certain degenerate cases. + * For example, suppose there are two identical edges A and B + * that belong to different contours (so without this code they would + * be processed by separate sweep events). Suppose another edge C + * crosses A and B from above. When A is processed, we split it + * at its intersection point with C. However this also splits C, + * so when we insert B we may compute a slightly different + * intersection point. This might leave two edges with a small + * gap between them. This kind of error is especially obvious + * when using boundary extraction (GLU_TESS_BOUNDARY_ONLY). + */ + vNext = (GLUvertex *)pqExtractMin( tess->pq ); /* __gl_pqSortExtractMin*/ + SpliceMergeVertices( tess, v->anEdge, vNext->anEdge ); + } + SweepEvent( tess, v ); + } + + /* Set tess->event for debugging purposes */ + /* __GL_DICTLISTKEY */ /* __GL_DICTLISTMIN */ + tess->event = ((ActiveRegion *) dictKey( dictMin( tess->dict )))->eUp->Org; + DebugEvent( tess ); + DoneEdgeDict( tess ); + DonePriorityQ( tess ); + + if ( !RemoveDegenerateFaces( tess->mesh ) ) return 0; + __gl_meshCheckMesh( tess->mesh ); + + return 1; +} diff --git a/GLU/sweep.h b/GLU/sweep.h new file mode 100644 index 0000000..feb68b0 --- /dev/null +++ b/GLU/sweep.h @@ -0,0 +1,77 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __sweep_h_ +#define __sweep_h_ + +#include "mesh.h" + +/* __gl_computeInterior( tess ) computes the planar arrangement specified + * by the given contours, and further subdivides this arrangement + * into regions. Each region is marked "inside" if it belongs + * to the polygon, according to the rule given by tess->windingRule. + * Each interior region is guaranteed be monotone. + */ +int __gl_computeInterior( GLUtesselator *tess ); + + +/* The following is here *only* for access by debugging routines */ + +#include "dict.h" + +/* For each pair of adjacent edges crossing the sweep line, there is + * an ActiveRegion to represent the region between them. The active + * regions are kept in sorted order in a dynamic dictionary. As the + * sweep line crosses each vertex, we update the affected regions. + */ + +struct ActiveRegion { + GLUhalfEdge *eUp; /* upper edge, directed right to left */ + DictNode *nodeUp; /* dictionary node corresponding to eUp */ + int windingNumber; /* used to determine which regions are + * inside the polygon */ + GLboolean inside; /* is this region inside the polygon? */ + GLboolean sentinel; /* marks fake edges at t = +/-infinity */ + GLboolean dirty; /* marks regions where the upper or lower + * edge has changed, but we haven't checked + * whether they intersect yet */ + GLboolean fixUpperEdge; /* marks temporary edges introduced when + * we process a "right vertex" (one without + * any edges leaving to the right) */ +}; + +#define RegionBelow(r) ((ActiveRegion *) dictKey(dictPred((r)->nodeUp))) +#define RegionAbove(r) ((ActiveRegion *) dictKey(dictSucc((r)->nodeUp))) + +#endif diff --git a/GLU/tess.c b/GLU/tess.c new file mode 100644 index 0000000..029a02c --- /dev/null +++ b/GLU/tess.c @@ -0,0 +1,628 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include +#include +#include "memalloc.h" +#include "tess.h" +#include "mesh.h" +#include "normal.h" +#include "sweep.h" +#include "tessmono.h" +#include "render.h" + +#define GLU_TESS_DEFAULT_TOLERANCE 0.0 +#define GLU_TESS_MESH 100112 /* void (*)(GLUmesh *mesh) */ + +#define TRUE 1 +#define FALSE 0 + +/*ARGSUSED*/ static void GLAPIENTRY noBegin( GLenum type ) {} +/*ARGSUSED*/ static void GLAPIENTRY noEdgeFlag( GLboolean boundaryEdge ) {} +/*ARGSUSED*/ static void GLAPIENTRY noVertex( void *data ) {} +/*ARGSUSED*/ static void GLAPIENTRY noEnd( void ) {} +/*ARGSUSED*/ static void GLAPIENTRY noError( GLenum errnum ) {} +/*ARGSUSED*/ static void GLAPIENTRY noCombine( GLdouble coords[3], void *data[4], + GLfloat weight[4], void **dataOut ) {} +/*ARGSUSED*/ static void GLAPIENTRY noMesh( GLUmesh *mesh ) {} + + +/*ARGSUSED*/ void GLAPIENTRY __gl_noBeginData( GLenum type, + void *polygonData ) {} +/*ARGSUSED*/ void GLAPIENTRY __gl_noEdgeFlagData( GLboolean boundaryEdge, + void *polygonData ) {} +/*ARGSUSED*/ void GLAPIENTRY __gl_noVertexData( void *data, + void *polygonData ) {} +/*ARGSUSED*/ void GLAPIENTRY __gl_noEndData( void *polygonData ) {} +/*ARGSUSED*/ void GLAPIENTRY __gl_noErrorData( GLenum errnum, + void *polygonData ) {} +/*ARGSUSED*/ void GLAPIENTRY __gl_noCombineData( GLdouble coords[3], + void *data[4], + GLfloat weight[4], + void **outData, + void *polygonData ) {} + +/* Half-edges are allocated in pairs (see mesh.c) */ +typedef struct { GLUhalfEdge e, eSym; } EdgePair; + +#undef MAX +#define MAX(a,b) ((a) > (b) ? (a) : (b)) +#define MAX_FAST_ALLOC (MAX(sizeof(EdgePair), \ + MAX(sizeof(GLUvertex),sizeof(GLUface)))) + + +GLUtesselator * GLAPIENTRY +gluNewTess( void ) +{ + GLUtesselator *tess; + + /* Only initialize fields which can be changed by the api. Other fields + * are initialized where they are used. + */ + + if (memInit( MAX_FAST_ALLOC ) == 0) { + return 0; /* out of memory */ + } + tess = (GLUtesselator *)memAlloc( sizeof( GLUtesselator )); + if (tess == NULL) { + return 0; /* out of memory */ + } + + tess->state = T_DORMANT; + + tess->normal[0] = 0; + tess->normal[1] = 0; + tess->normal[2] = 0; + + tess->relTolerance = GLU_TESS_DEFAULT_TOLERANCE; + tess->windingRule = GLU_TESS_WINDING_ODD; + tess->flagBoundary = FALSE; + tess->boundaryOnly = FALSE; + + tess->callBegin = &noBegin; + tess->callEdgeFlag = &noEdgeFlag; + tess->callVertex = &noVertex; + tess->callEnd = &noEnd; + + tess->callError = &noError; + tess->callCombine = &noCombine; + tess->callMesh = &noMesh; + + tess->callBeginData= &__gl_noBeginData; + tess->callEdgeFlagData= &__gl_noEdgeFlagData; + tess->callVertexData= &__gl_noVertexData; + tess->callEndData= &__gl_noEndData; + tess->callErrorData= &__gl_noErrorData; + tess->callCombineData= &__gl_noCombineData; + + tess->polygonData= NULL; + + return tess; +} + +static void MakeDormant( GLUtesselator *tess ) +{ + /* Return the tessellator to its original dormant state. */ + + if( tess->mesh != NULL ) { + __gl_meshDeleteMesh( tess->mesh ); + } + tess->state = T_DORMANT; + tess->lastEdge = NULL; + tess->mesh = NULL; +} + +#define RequireState( tess, s ) if( tess->state != s ) GotoState(tess,s) + +static void GotoState( GLUtesselator *tess, enum TessState newState ) +{ + while( tess->state != newState ) { + /* We change the current state one level at a time, to get to + * the desired state. + */ + if( tess->state < newState ) { + switch( tess->state ) { + case T_DORMANT: + CALL_ERROR_OR_ERROR_DATA( GLU_TESS_MISSING_BEGIN_POLYGON ); + gluTessBeginPolygon( tess, NULL ); + break; + case T_IN_POLYGON: + CALL_ERROR_OR_ERROR_DATA( GLU_TESS_MISSING_BEGIN_CONTOUR ); + gluTessBeginContour( tess ); + break; + default: + ; + } + } else { + switch( tess->state ) { + case T_IN_CONTOUR: + CALL_ERROR_OR_ERROR_DATA( GLU_TESS_MISSING_END_CONTOUR ); + gluTessEndContour( tess ); + break; + case T_IN_POLYGON: + CALL_ERROR_OR_ERROR_DATA( GLU_TESS_MISSING_END_POLYGON ); + /* gluTessEndPolygon( tess ) is too much work! */ + MakeDormant( tess ); + break; + default: + ; + } + } + } +} + + +void GLAPIENTRY +gluDeleteTess( GLUtesselator *tess ) +{ + RequireState( tess, T_DORMANT ); + memFree( tess ); +} + + +void GLAPIENTRY +gluTessProperty( GLUtesselator *tess, GLenum which, GLdouble value ) +{ + GLenum windingRule; + + switch( which ) { + case GLU_TESS_TOLERANCE: + if( value < 0.0 || value > 1.0 ) break; + tess->relTolerance = value; + return; + + case GLU_TESS_WINDING_RULE: + windingRule = (GLenum) value; + if( windingRule != value ) break; /* not an integer */ + + switch( windingRule ) { + case GLU_TESS_WINDING_ODD: + case GLU_TESS_WINDING_NONZERO: + case GLU_TESS_WINDING_POSITIVE: + case GLU_TESS_WINDING_NEGATIVE: + case GLU_TESS_WINDING_ABS_GEQ_TWO: + tess->windingRule = windingRule; + return; + default: + break; + } + + case GLU_TESS_BOUNDARY_ONLY: + tess->boundaryOnly = (value != 0); + return; + + default: + CALL_ERROR_OR_ERROR_DATA( GLU_INVALID_ENUM ); + return; + } + CALL_ERROR_OR_ERROR_DATA( GLU_INVALID_VALUE ); +} + +/* Returns tessellator property */ +void GLAPIENTRY +gluGetTessProperty( GLUtesselator *tess, GLenum which, GLdouble *value ) +{ + switch (which) { + case GLU_TESS_TOLERANCE: + /* tolerance should be in range [0..1] */ + assert(0.0 <= tess->relTolerance && tess->relTolerance <= 1.0); + *value= tess->relTolerance; + break; + case GLU_TESS_WINDING_RULE: + assert(tess->windingRule == GLU_TESS_WINDING_ODD || + tess->windingRule == GLU_TESS_WINDING_NONZERO || + tess->windingRule == GLU_TESS_WINDING_POSITIVE || + tess->windingRule == GLU_TESS_WINDING_NEGATIVE || + tess->windingRule == GLU_TESS_WINDING_ABS_GEQ_TWO); + *value= tess->windingRule; + break; + case GLU_TESS_BOUNDARY_ONLY: + assert(tess->boundaryOnly == TRUE || tess->boundaryOnly == FALSE); + *value= tess->boundaryOnly; + break; + default: + *value= 0.0; + CALL_ERROR_OR_ERROR_DATA( GLU_INVALID_ENUM ); + break; + } +} /* gluGetTessProperty() */ + +void GLAPIENTRY +gluTessNormal( GLUtesselator *tess, GLdouble x, GLdouble y, GLdouble z ) +{ + tess->normal[0] = x; + tess->normal[1] = y; + tess->normal[2] = z; +} + +void GLAPIENTRY +gluTessCallback( GLUtesselator *tess, GLenum which, _GLUfuncptr fn) +{ + switch( which ) { + case GLU_TESS_BEGIN: + tess->callBegin = (fn == NULL) ? &noBegin : (void (GLAPIENTRY *)(GLenum)) fn; + return; + case GLU_TESS_BEGIN_DATA: + tess->callBeginData = (fn == NULL) ? + &__gl_noBeginData : (void (GLAPIENTRY *)(GLenum, void *)) fn; + return; + case GLU_TESS_EDGE_FLAG: + tess->callEdgeFlag = (fn == NULL) ? &noEdgeFlag : + (void (GLAPIENTRY *)(GLboolean)) fn; + /* If the client wants boundary edges to be flagged, + * we render everything as separate triangles (no strips or fans). + */ + tess->flagBoundary = (fn != NULL); + return; + case GLU_TESS_EDGE_FLAG_DATA: + tess->callEdgeFlagData= (fn == NULL) ? + &__gl_noEdgeFlagData : (void (GLAPIENTRY *)(GLboolean, void *)) fn; + /* If the client wants boundary edges to be flagged, + * we render everything as separate triangles (no strips or fans). + */ + tess->flagBoundary = (fn != NULL); + return; + case GLU_TESS_VERTEX: + tess->callVertex = (fn == NULL) ? &noVertex : + (void (GLAPIENTRY *)(void *)) fn; + return; + case GLU_TESS_VERTEX_DATA: + tess->callVertexData = (fn == NULL) ? + &__gl_noVertexData : (void (GLAPIENTRY *)(void *, void *)) fn; + return; + case GLU_TESS_END: + tess->callEnd = (fn == NULL) ? &noEnd : (void (GLAPIENTRY *)(void)) fn; + return; + case GLU_TESS_END_DATA: + tess->callEndData = (fn == NULL) ? &__gl_noEndData : + (void (GLAPIENTRY *)(void *)) fn; + return; + case GLU_TESS_ERROR: + tess->callError = (fn == NULL) ? &noError : (void (GLAPIENTRY *)(GLenum)) fn; + return; + case GLU_TESS_ERROR_DATA: + tess->callErrorData = (fn == NULL) ? + &__gl_noErrorData : (void (GLAPIENTRY *)(GLenum, void *)) fn; + return; + case GLU_TESS_COMBINE: + tess->callCombine = (fn == NULL) ? &noCombine : + (void (GLAPIENTRY *)(GLdouble [3],void *[4], GLfloat [4], void ** )) fn; + return; + case GLU_TESS_COMBINE_DATA: + tess->callCombineData = (fn == NULL) ? &__gl_noCombineData : + (void (GLAPIENTRY *)(GLdouble [3], + void *[4], + GLfloat [4], + void **, + void *)) fn; + return; + case GLU_TESS_MESH: + tess->callMesh = (fn == NULL) ? &noMesh : (void (GLAPIENTRY *)(GLUmesh *)) fn; + return; + default: + CALL_ERROR_OR_ERROR_DATA( GLU_INVALID_ENUM ); + return; + } +} + +static int AddVertex( GLUtesselator *tess, GLdouble coords[3], void *data ) +{ + GLUhalfEdge *e; + + e = tess->lastEdge; + if( e == NULL ) { + /* Make a self-loop (one vertex, one edge). */ + + e = __gl_meshMakeEdge( tess->mesh ); + if (e == NULL) return 0; + if ( !__gl_meshSplice( e, e->Sym ) ) return 0; + } else { + /* Create a new vertex and edge which immediately follow e + * in the ordering around the left face. + */ + if (__gl_meshSplitEdge( e ) == NULL) return 0; + e = e->Lnext; + } + + /* The new vertex is now e->Org. */ + e->Org->data = data; + e->Org->coords[0] = coords[0]; + e->Org->coords[1] = coords[1]; + e->Org->coords[2] = coords[2]; + + /* The winding of an edge says how the winding number changes as we + * cross from the edge''s right face to its left face. We add the + * vertices in such an order that a CCW contour will add +1 to + * the winding number of the region inside the contour. + */ + e->winding = 1; + e->Sym->winding = -1; + + tess->lastEdge = e; + + return 1; +} + + +static void CacheVertex( GLUtesselator *tess, GLdouble coords[3], void *data ) +{ + CachedVertex *v = &tess->cache[tess->cacheCount]; + + v->data = data; + v->coords[0] = coords[0]; + v->coords[1] = coords[1]; + v->coords[2] = coords[2]; + ++tess->cacheCount; +} + + +static int EmptyCache( GLUtesselator *tess ) +{ + CachedVertex *v = tess->cache; + CachedVertex *vLast; + + tess->mesh = __gl_meshNewMesh(); + if (tess->mesh == NULL) return 0; + + for( vLast = v + tess->cacheCount; v < vLast; ++v ) { + if ( !AddVertex( tess, v->coords, v->data ) ) return 0; + } + tess->cacheCount = 0; + tess->emptyCache = FALSE; + + return 1; +} + + +void GLAPIENTRY +gluTessVertex( GLUtesselator *tess, GLdouble coords[3], void *data ) +{ + int i, tooLarge = FALSE; + GLdouble x, clamped[3]; + + RequireState( tess, T_IN_CONTOUR ); + + if( tess->emptyCache ) { + if ( !EmptyCache( tess ) ) { + CALL_ERROR_OR_ERROR_DATA( GLU_OUT_OF_MEMORY ); + return; + } + tess->lastEdge = NULL; + } + for( i = 0; i < 3; ++i ) { + x = coords[i]; + if( x < - GLU_TESS_MAX_COORD ) { + x = - GLU_TESS_MAX_COORD; + tooLarge = TRUE; + } + if( x > GLU_TESS_MAX_COORD ) { + x = GLU_TESS_MAX_COORD; + tooLarge = TRUE; + } + clamped[i] = x; + } + if( tooLarge ) { + CALL_ERROR_OR_ERROR_DATA( GLU_TESS_COORD_TOO_LARGE ); + } + + if( tess->mesh == NULL ) { + if( tess->cacheCount < TESS_MAX_CACHE ) { + CacheVertex( tess, clamped, data ); + return; + } + if ( !EmptyCache( tess ) ) { + CALL_ERROR_OR_ERROR_DATA( GLU_OUT_OF_MEMORY ); + return; + } + } + if ( !AddVertex( tess, clamped, data ) ) { + CALL_ERROR_OR_ERROR_DATA( GLU_OUT_OF_MEMORY ); + } +} + + +void GLAPIENTRY +gluTessBeginPolygon( GLUtesselator *tess, void *data ) +{ + RequireState( tess, T_DORMANT ); + + tess->state = T_IN_POLYGON; + tess->cacheCount = 0; + tess->emptyCache = FALSE; + tess->mesh = NULL; + + tess->polygonData= data; +} + + +void GLAPIENTRY +gluTessBeginContour( GLUtesselator *tess ) +{ + RequireState( tess, T_IN_POLYGON ); + + tess->state = T_IN_CONTOUR; + tess->lastEdge = NULL; + if( tess->cacheCount > 0 ) { + /* Just set a flag so we don't get confused by empty contours + * -- these can be generated accidentally with the obsolete + * NextContour() interface. + */ + tess->emptyCache = TRUE; + } +} + + +void GLAPIENTRY +gluTessEndContour( GLUtesselator *tess ) +{ + RequireState( tess, T_IN_CONTOUR ); + tess->state = T_IN_POLYGON; +} + +void GLAPIENTRY +gluTessEndPolygon( GLUtesselator *tess ) +{ + GLUmesh *mesh; + + if (setjmp(tess->env) != 0) { + /* come back here if out of memory */ + CALL_ERROR_OR_ERROR_DATA( GLU_OUT_OF_MEMORY ); + return; + } + + RequireState( tess, T_IN_POLYGON ); + tess->state = T_DORMANT; + + if( tess->mesh == NULL ) { + if( ! tess->flagBoundary && tess->callMesh == &noMesh ) { + + /* Try some special code to make the easy cases go quickly + * (eg. convex polygons). This code does NOT handle multiple contours, + * intersections, edge flags, and of course it does not generate + * an explicit mesh either. + */ + if( __gl_renderCache( tess )) { + tess->polygonData= NULL; + return; + } + } + if ( !EmptyCache( tess ) ) longjmp(tess->env,1); /* could've used a label*/ + } + + /* Determine the polygon normal and project vertices onto the plane + * of the polygon. + */ + __gl_projectPolygon( tess ); + + /* __gl_computeInterior( tess ) computes the planar arrangement specified + * by the given contours, and further subdivides this arrangement + * into regions. Each region is marked "inside" if it belongs + * to the polygon, according to the rule given by tess->windingRule. + * Each interior region is guaranteed be monotone. + */ + if ( !__gl_computeInterior( tess ) ) { + longjmp(tess->env,1); /* could've used a label */ + } + + mesh = tess->mesh; + if( ! tess->fatalError ) { + int rc = 1; + + /* If the user wants only the boundary contours, we throw away all edges + * except those which separate the interior from the exterior. + * Otherwise we tessellate all the regions marked "inside". + */ + if( tess->boundaryOnly ) { + rc = __gl_meshSetWindingNumber( mesh, 1, TRUE ); + } else { + rc = __gl_meshTessellateInterior( mesh ); + } + if (rc == 0) longjmp(tess->env,1); /* could've used a label */ + + __gl_meshCheckMesh( mesh ); + + if( tess->callBegin != &noBegin || tess->callEnd != &noEnd + || tess->callVertex != &noVertex || tess->callEdgeFlag != &noEdgeFlag + || tess->callBeginData != &__gl_noBeginData + || tess->callEndData != &__gl_noEndData + || tess->callVertexData != &__gl_noVertexData + || tess->callEdgeFlagData != &__gl_noEdgeFlagData ) + { + if( tess->boundaryOnly ) { + __gl_renderBoundary( tess, mesh ); /* output boundary contours */ + } else { + __gl_renderMesh( tess, mesh ); /* output strips and fans */ + } + } + if( tess->callMesh != &noMesh ) { + + /* Throw away the exterior faces, so that all faces are interior. + * This way the user doesn't have to check the "inside" flag, + * and we don't need to even reveal its existence. It also leaves + * the freedom for an implementation to not generate the exterior + * faces in the first place. + */ + __gl_meshDiscardExterior( mesh ); + (*tess->callMesh)( mesh ); /* user wants the mesh itself */ + tess->mesh = NULL; + tess->polygonData= NULL; + return; + } + } + __gl_meshDeleteMesh( mesh ); + tess->polygonData= NULL; + tess->mesh = NULL; +} + + +/*XXXblythe unused function*/ +#if 0 +void GLAPIENTRY +gluDeleteMesh( GLUmesh *mesh ) +{ + __gl_meshDeleteMesh( mesh ); +} +#endif + + + +/*******************************************************/ + +/* Obsolete calls -- for backward compatibility */ + +void GLAPIENTRY +gluBeginPolygon( GLUtesselator *tess ) +{ + gluTessBeginPolygon( tess, NULL ); + gluTessBeginContour( tess ); +} + + +/*ARGSUSED*/ +void GLAPIENTRY +gluNextContour( GLUtesselator *tess, GLenum type ) +{ + gluTessEndContour( tess ); + gluTessBeginContour( tess ); +} + + +void GLAPIENTRY +gluEndPolygon( GLUtesselator *tess ) +{ + gluTessEndContour( tess ); + gluTessEndPolygon( tess ); +} diff --git a/GLU/tess.h b/GLU/tess.h new file mode 100644 index 0000000..064477d --- /dev/null +++ b/GLU/tess.h @@ -0,0 +1,165 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __tess_h_ +#define __tess_h_ + +#include "GL/glu.h" +#include +#include "mesh.h" +#include "dict.h" +#include "priorityq.h" + +/* The begin/end calls must be properly nested. We keep track of + * the current state to enforce the ordering. + */ +enum TessState { T_DORMANT, T_IN_POLYGON, T_IN_CONTOUR }; + +/* We cache vertex data for single-contour polygons so that we can + * try a quick-and-dirty decomposition first. + */ +#define TESS_MAX_CACHE 100 + +typedef struct CachedVertex { + GLdouble coords[3]; + void *data; +} CachedVertex; + +struct GLUtesselator { + + /*** state needed for collecting the input data ***/ + + enum TessState state; /* what begin/end calls have we seen? */ + + GLUhalfEdge *lastEdge; /* lastEdge->Org is the most recent vertex */ + GLUmesh *mesh; /* stores the input contours, and eventually + the tessellation itself */ + + void (GLAPIENTRY *callError)( GLenum errnum ); + + /*** state needed for projecting onto the sweep plane ***/ + + GLdouble normal[3]; /* user-specified normal (if provided) */ + GLdouble sUnit[3]; /* unit vector in s-direction (debugging) */ + GLdouble tUnit[3]; /* unit vector in t-direction (debugging) */ + + /*** state needed for the line sweep ***/ + + GLdouble relTolerance; /* tolerance for merging features */ + GLenum windingRule; /* rule for determining polygon interior */ + GLboolean fatalError; /* fatal error: needed combine callback */ + + Dict *dict; /* edge dictionary for sweep line */ + PriorityQ *pq; /* priority queue of vertex events */ + GLUvertex *event; /* current sweep event being processed */ + + void (GLAPIENTRY *callCombine)( GLdouble coords[3], void *data[4], + GLfloat weight[4], void **outData ); + + /*** state needed for rendering callbacks (see render.c) ***/ + + GLboolean flagBoundary; /* mark boundary edges (use EdgeFlag) */ + GLboolean boundaryOnly; /* Extract contours, not triangles */ + GLUface *lonelyTriList; + /* list of triangles which could not be rendered as strips or fans */ + + void (GLAPIENTRY *callBegin)( GLenum type ); + void (GLAPIENTRY *callEdgeFlag)( GLboolean boundaryEdge ); + void (GLAPIENTRY *callVertex)( void *data ); + void (GLAPIENTRY *callEnd)( void ); + void (GLAPIENTRY *callMesh)( GLUmesh *mesh ); + + + /*** state needed to cache single-contour polygons for renderCache() */ + + GLboolean emptyCache; /* empty cache on next vertex() call */ + int cacheCount; /* number of cached vertices */ + CachedVertex cache[TESS_MAX_CACHE]; /* the vertex data */ + + /*** rendering callbacks that also pass polygon data ***/ + void (GLAPIENTRY *callBeginData)( GLenum type, void *polygonData ); + void (GLAPIENTRY *callEdgeFlagData)( GLboolean boundaryEdge, + void *polygonData ); + void (GLAPIENTRY *callVertexData)( void *data, void *polygonData ); + void (GLAPIENTRY *callEndData)( void *polygonData ); + void (GLAPIENTRY *callErrorData)( GLenum errnum, void *polygonData ); + void (GLAPIENTRY *callCombineData)( GLdouble coords[3], void *data[4], + GLfloat weight[4], void **outData, + void *polygonData ); + + jmp_buf env; /* place to jump to when memAllocs fail */ + + void *polygonData; /* client data for current polygon */ +}; + +void GLAPIENTRY __gl_noBeginData( GLenum type, void *polygonData ); +void GLAPIENTRY __gl_noEdgeFlagData( GLboolean boundaryEdge, void *polygonData ); +void GLAPIENTRY __gl_noVertexData( void *data, void *polygonData ); +void GLAPIENTRY __gl_noEndData( void *polygonData ); +void GLAPIENTRY __gl_noErrorData( GLenum errnum, void *polygonData ); +void GLAPIENTRY __gl_noCombineData( GLdouble coords[3], void *data[4], + GLfloat weight[4], void **outData, + void *polygonData ); + +#define CALL_BEGIN_OR_BEGIN_DATA(a) \ + if (tess->callBeginData != &__gl_noBeginData) \ + (*tess->callBeginData)((a),tess->polygonData); \ + else (*tess->callBegin)((a)); + +#define CALL_VERTEX_OR_VERTEX_DATA(a) \ + if (tess->callVertexData != &__gl_noVertexData) \ + (*tess->callVertexData)((a),tess->polygonData); \ + else (*tess->callVertex)((a)); + +#define CALL_EDGE_FLAG_OR_EDGE_FLAG_DATA(a) \ + if (tess->callEdgeFlagData != &__gl_noEdgeFlagData) \ + (*tess->callEdgeFlagData)((a),tess->polygonData); \ + else (*tess->callEdgeFlag)((a)); + +#define CALL_END_OR_END_DATA() \ + if (tess->callEndData != &__gl_noEndData) \ + (*tess->callEndData)(tess->polygonData); \ + else (*tess->callEnd)(); + +#define CALL_COMBINE_OR_COMBINE_DATA(a,b,c,d) \ + if (tess->callCombineData != &__gl_noCombineData) \ + (*tess->callCombineData)((a),(b),(c),(d),tess->polygonData); \ + else (*tess->callCombine)((a),(b),(c),(d)); + +#define CALL_ERROR_OR_ERROR_DATA(a) \ + if (tess->callErrorData != &__gl_noErrorData) \ + (*tess->callErrorData)((a),tess->polygonData); \ + else (*tess->callError)((a)); + +#endif diff --git a/GLU/tessmono.c b/GLU/tessmono.c new file mode 100644 index 0000000..4d08440 --- /dev/null +++ b/GLU/tessmono.c @@ -0,0 +1,201 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#include "gluos.h" +#include +#include "geom.h" +#include "mesh.h" +#include "tessmono.h" +#include + +#define AddWinding(eDst,eSrc) (eDst->winding += eSrc->winding, \ + eDst->Sym->winding += eSrc->Sym->winding) + +/* __gl_meshTessellateMonoRegion( face ) tessellates a monotone region + * (what else would it do??) The region must consist of a single + * loop of half-edges (see mesh.h) oriented CCW. "Monotone" in this + * case means that any vertical line intersects the interior of the + * region in a single interval. + * + * Tessellation consists of adding interior edges (actually pairs of + * half-edges), to split the region into non-overlapping triangles. + * + * The basic idea is explained in Preparata and Shamos (which I don''t + * have handy right now), although their implementation is more + * complicated than this one. The are two edge chains, an upper chain + * and a lower chain. We process all vertices from both chains in order, + * from right to left. + * + * The algorithm ensures that the following invariant holds after each + * vertex is processed: the untessellated region consists of two + * chains, where one chain (say the upper) is a single edge, and + * the other chain is concave. The left vertex of the single edge + * is always to the left of all vertices in the concave chain. + * + * Each step consists of adding the rightmost unprocessed vertex to one + * of the two chains, and forming a fan of triangles from the rightmost + * of two chain endpoints. Determining whether we can add each triangle + * to the fan is a simple orientation test. By making the fan as large + * as possible, we restore the invariant (check it yourself). + */ +int __gl_meshTessellateMonoRegion( GLUface *face ) +{ + GLUhalfEdge *up, *lo; + + /* All edges are oriented CCW around the boundary of the region. + * First, find the half-edge whose origin vertex is rightmost. + * Since the sweep goes from left to right, face->anEdge should + * be close to the edge we want. + */ + up = face->anEdge; + assert( up->Lnext != up && up->Lnext->Lnext != up ); + + for( ; VertLeq( up->Dst, up->Org ); up = up->Lprev ) + ; + for( ; VertLeq( up->Org, up->Dst ); up = up->Lnext ) + ; + lo = up->Lprev; + + while( up->Lnext != lo ) { + if( VertLeq( up->Dst, lo->Org )) { + /* up->Dst is on the left. It is safe to form triangles from lo->Org. + * The EdgeGoesLeft test guarantees progress even when some triangles + * are CW, given that the upper and lower chains are truly monotone. + */ + while( lo->Lnext != up && (EdgeGoesLeft( lo->Lnext ) + || EdgeSign( lo->Org, lo->Dst, lo->Lnext->Dst ) <= 0 )) { + GLUhalfEdge *tempHalfEdge= __gl_meshConnect( lo->Lnext, lo ); + if (tempHalfEdge == NULL) return 0; + lo = tempHalfEdge->Sym; + } + lo = lo->Lprev; + } else { + /* lo->Org is on the left. We can make CCW triangles from up->Dst. */ + while( lo->Lnext != up && (EdgeGoesRight( up->Lprev ) + || EdgeSign( up->Dst, up->Org, up->Lprev->Org ) >= 0 )) { + GLUhalfEdge *tempHalfEdge= __gl_meshConnect( up, up->Lprev ); + if (tempHalfEdge == NULL) return 0; + up = tempHalfEdge->Sym; + } + up = up->Lnext; + } + } + + /* Now lo->Org == up->Dst == the leftmost vertex. The remaining region + * can be tessellated in a fan from this leftmost vertex. + */ + assert( lo->Lnext != up ); + while( lo->Lnext->Lnext != up ) { + GLUhalfEdge *tempHalfEdge= __gl_meshConnect( lo->Lnext, lo ); + if (tempHalfEdge == NULL) return 0; + lo = tempHalfEdge->Sym; + } + + return 1; +} + + +/* __gl_meshTessellateInterior( mesh ) tessellates each region of + * the mesh which is marked "inside" the polygon. Each such region + * must be monotone. + */ +int __gl_meshTessellateInterior( GLUmesh *mesh ) +{ + GLUface *f, *next; + + /*LINTED*/ + for( f = mesh->fHead.next; f != &mesh->fHead; f = next ) { + /* Make sure we don''t try to tessellate the new triangles. */ + next = f->next; + if( f->inside ) { + if ( !__gl_meshTessellateMonoRegion( f ) ) return 0; + } + } + + return 1; +} + + +/* __gl_meshDiscardExterior( mesh ) zaps (ie. sets to NULL) all faces + * which are not marked "inside" the polygon. Since further mesh operations + * on NULL faces are not allowed, the main purpose is to clean up the + * mesh so that exterior loops are not represented in the data structure. + */ +void __gl_meshDiscardExterior( GLUmesh *mesh ) +{ + GLUface *f, *next; + + /*LINTED*/ + for( f = mesh->fHead.next; f != &mesh->fHead; f = next ) { + /* Since f will be destroyed, save its next pointer. */ + next = f->next; + if( ! f->inside ) { + __gl_meshZapFace( f ); + } + } +} + +#define MARKED_FOR_DELETION 0x7fffffff + +/* __gl_meshSetWindingNumber( mesh, value, keepOnlyBoundary ) resets the + * winding numbers on all edges so that regions marked "inside" the + * polygon have a winding number of "value", and regions outside + * have a winding number of 0. + * + * If keepOnlyBoundary is TRUE, it also deletes all edges which do not + * separate an interior region from an exterior one. + */ +int __gl_meshSetWindingNumber( GLUmesh *mesh, int value, + GLboolean keepOnlyBoundary ) +{ + GLUhalfEdge *e, *eNext; + + for( e = mesh->eHead.next; e != &mesh->eHead; e = eNext ) { + eNext = e->next; + if( e->Rface->inside != e->Lface->inside ) { + + /* This is a boundary edge (one side is interior, one is exterior). */ + e->winding = (e->Lface->inside) ? value : -value; + } else { + + /* Both regions are interior, or both are exterior. */ + if( ! keepOnlyBoundary ) { + e->winding = 0; + } else { + if ( !__gl_meshDelete( e ) ) return 0; + } + } + } + return 1; +} diff --git a/GLU/tessmono.h b/GLU/tessmono.h new file mode 100644 index 0000000..8ee1b2f --- /dev/null +++ b/GLU/tessmono.h @@ -0,0 +1,71 @@ +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ +/* +** Author: Eric Veach, July 1994. +** +*/ + +#ifndef __tessmono_h_ +#define __tessmono_h_ + +/* __gl_meshTessellateMonoRegion( face ) tessellates a monotone region + * (what else would it do??) The region must consist of a single + * loop of half-edges (see mesh.h) oriented CCW. "Monotone" in this + * case means that any vertical line intersects the interior of the + * region in a single interval. + * + * Tessellation consists of adding interior edges (actually pairs of + * half-edges), to split the region into non-overlapping triangles. + * + * __gl_meshTessellateInterior( mesh ) tessellates each region of + * the mesh which is marked "inside" the polygon. Each such region + * must be monotone. + * + * __gl_meshDiscardExterior( mesh ) zaps (ie. sets to NULL) all faces + * which are not marked "inside" the polygon. Since further mesh operations + * on NULL faces are not allowed, the main purpose is to clean up the + * mesh so that exterior loops are not represented in the data structure. + * + * __gl_meshSetWindingNumber( mesh, value, keepOnlyBoundary ) resets the + * winding numbers on all edges so that regions marked "inside" the + * polygon have a winding number of "value", and regions outside + * have a winding number of 0. + * + * If keepOnlyBoundary is TRUE, it also deletes all edges which do not + * separate an interior region from an exterior one. + */ + +int __gl_meshTessellateMonoRegion( GLUface *face ); +int __gl_meshTessellateInterior( GLUmesh *mesh ); +void __gl_meshDiscardExterior( GLUmesh *mesh ); +int __gl_meshSetWindingNumber( GLUmesh *mesh, int value, + GLboolean keepOnlyBoundary ); + +#endif diff --git a/GLU/util.c b/GLU/util.c new file mode 100644 index 0000000..90d58f3 --- /dev/null +++ b/GLU/util.c @@ -0,0 +1,90 @@ +// These are just the bits of GLU we use so we can ditch the external +// dependency (since it turns out to be complicated, as it depends on libGL, +// which we load dynamically, etc). This is from SGI's open source version. + +/* + * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) + * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice including the dates of first publication and + * either this permission notice or a reference to + * http://oss.sgi.com/projects/FreeB/ + * shall be included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Except as contained in this notice, the name of Silicon Graphics, Inc. + * shall not be used in advertising or otherwise to promote the sale, use or + * other dealings in this Software without prior written authorization from + * Silicon Graphics, Inc. + */ + +#include +#include +#include "GL/gl.h" +#include "GL/glu.h" + +/* +** Make m an identity matrix +*/ +static void __gluMakeIdentityd(GLdouble m[16]) +{ + m[0+4*0] = 1; m[0+4*1] = 0; m[0+4*2] = 0; m[0+4*3] = 0; + m[1+4*0] = 0; m[1+4*1] = 1; m[1+4*2] = 0; m[1+4*3] = 0; + m[2+4*0] = 0; m[2+4*1] = 0; m[2+4*2] = 1; m[2+4*3] = 0; + m[3+4*0] = 0; m[3+4*1] = 0; m[3+4*2] = 0; m[3+4*3] = 1; +} + +static void __gluMakeIdentityf(GLfloat m[16]) +{ + m[0+4*0] = 1; m[0+4*1] = 0; m[0+4*2] = 0; m[0+4*3] = 0; + m[1+4*0] = 0; m[1+4*1] = 1; m[1+4*2] = 0; m[1+4*3] = 0; + m[2+4*0] = 0; m[2+4*1] = 0; m[2+4*2] = 1; m[2+4*3] = 0; + m[3+4*0] = 0; m[3+4*1] = 0; m[3+4*2] = 0; m[3+4*3] = 1; +} + +void GLAPIENTRY +gluOrtho2D(GLdouble left, GLdouble right, GLdouble bottom, GLdouble top) +{ + glOrtho(left, right, bottom, top, -1, 1); +} + +#define __glPi 3.14159265358979323846 + +void GLAPIENTRY +gluPerspective(GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar) +{ + GLdouble m[4][4]; + double sine, cotangent, deltaZ; + double radians = fovy / 2 * __glPi / 180; + + deltaZ = zFar - zNear; + sine = sin(radians); + if ((deltaZ == 0) || (sine == 0) || (aspect == 0)) { + return; + } + cotangent = cos(radians) / sine; + + __gluMakeIdentityd(&m[0][0]); + m[0][0] = cotangent / aspect; + m[1][1] = cotangent; + m[2][2] = -(zFar + zNear) / deltaZ; + m[2][3] = -1; + m[3][2] = -2 * zNear * zFar / deltaZ; + m[3][3] = 0; + glMultMatrixd(&m[0][0]); +} + -- 2.39.5