Source/Stereo.cpp

   1 /*
   2 Copyright (C) 2003, 2010 - Wolfire Games
   3
   4 This file is part of Lugaru.
   5
   6 Lugaru is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU General Public License
   8 as published by the Free Software Foundation; either version 2
   9 of the License, or (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14
  15 See the GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  20 */
  21
  22 #include "Game.h"
  23 #include "Stereo.h"
  24
  25
  26 extern int kContextWidth;
  27 extern int kContextHeight;
  28
  29 bool CanInitStereo(StereoMode mode)
  30 {
  31     GLint stencilbits = 0;
  32
  33     switch (mode) {
  34     case stereoNone:
  35         return true;
  36         break;
  37     case stereoAnaglyph:
  38         return true;
  39         break;
  40     case stereoHorizontalInterlaced:
  41     case stereoVerticalInterlaced:
  42         glGetIntegerv(GL_STENCIL_BITS, &stencilbits);
  43         if ( stencilbits < 1 ) {
  44             fprintf(stderr, "Failed to get a stencil buffer, interlaced stereo not available.\n");
  45             return false;
  46         } else {
  47             fprintf(stderr, "Stencil buffer has %i bits, good.\n", stencilbits);
  48         }
  49         return true;
  50         break;
  51     default:
  52         return false;
  53     }
  54
  55 }
  56
  57 void InitStereo(StereoMode mode)
  58 {
  59     switch (mode) {
  60     case stereoNone:
  61         glDisable( GL_STENCIL_TEST);
  62         return;
  63     case stereoAnaglyph:
  64         glDisable( GL_STENCIL_TEST);
  65         return;
  66     case stereoHorizontalInterlaced:
  67     case stereoVerticalInterlaced:
  68
  69         fprintf(stderr, "Screen width is %i, height is %i\n", kContextWidth, kContextHeight);
  70
  71         // Setup stencil buffer
  72         glDisable( GL_DEPTH_TEST);
  73         glDisable(GL_CULL_FACE);
  74         glDisable(GL_LIGHTING);
  75         glDisable(GL_TEXTURE_2D);
  76
  77         glEnable( GL_STENCIL_TEST);
  78         glClearStencil(0);
  79         glClear(  GL_STENCIL_BUFFER_BIT );
  80         glStencilFunc(GL_ALWAYS, 0x1, 0x1);
  81         glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
  82
  83         // Setup viewport
  84         glViewport(0, 0, kContextWidth, kContextHeight);
  85         glMatrixMode(GL_PROJECTION);
  86         glPushMatrix();
  87         glLoadIdentity();
  88         glOrtho((GLdouble)0, (GLdouble)kContextWidth, (GLdouble)kContextHeight, 0, -1, 1);
  89         glMatrixMode(GL_MODELVIEW);
  90         glPushMatrix();
  91         glLoadIdentity();
  92         glColorMask( GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE );
  93         glDisable(GL_LINE_SMOOTH);
  94
  95         // Add 0.5 to the coordinates, because OpenGL considers a pixel should be
  96         // turned on when a line passes through the center of it.
  97         if ( mode == stereoHorizontalInterlaced ) {
  98             for (int y = 0; y < kContextHeight; y += 2) {
  99                 glBegin(GL_LINES);
 100                 glVertex3f(0.5, y + 0.5, 0);
 101                 glVertex3f(kContextWidth + 0.5, y + 0.5, 0);
 102                 glEnd();
 103             }
 104         } else {
 105             for (int x = 0; x < kContextWidth; x += 2) {
 106                 glBegin(GL_LINES);
 107                 glVertex3f(x + 0.5, 0.5, 0);
 108                 glVertex3f(x + 0.5, kContextHeight + 0.5, 0);
 109                 glEnd();
 110             }
 111         }
 112
 113         glColorMask( GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE );
 114
 115         glPopMatrix();
 116         glMatrixMode(GL_PROJECTION);
 117         glPopMatrix();
 118
 119         glStencilFunc(GL_NOTEQUAL, 0x01, 0x01);
 120         glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
 121         glEnable( GL_DEPTH_TEST);
 122         glEnable(GL_CULL_FACE);
 123         glEnable(GL_LIGHTING);
 124         glEnable(GL_TEXTURE_2D);
 125
 126     }
 127
 128 }
 129
 130 const char* StereoModeName(StereoMode mode)
 131 {
 132     switch (mode) {
 133     case stereoNone:
 134         return "None";
 135         break;
 136     case stereoAnaglyph:
 137         return "Anaglyph";
 138         break;
 139     case stereoHorizontalInterlaced:
 140         return "Horizontal interlacing";
 141         break;
 142     case stereoVerticalInterlaced:
 143         return "Vertical interlacing";
 144         break;
 145     case stereoHorizontalSplit:
 146         return "Horizontal split";
 147         break;
 148     case stereoVerticalSplit:
 149         return "Vertical split";
 150         break;
 151     case stereoOpenGL:
 152         return "OpenGL";
 153         break;
 154     default:
 155         return "(error)";
 156         break;
 157     }
 158 }