1 ;;; Gacela, a GNU Common Lisp extension for fast games development
2 ;;; Copyright (C) 2009 by Javier Sancho Fernandez <jsf at jsancho dot org>
4 ;;; This program is free software: you can redistribute it and/or modify
5 ;;; it under the terms of the GNU General Public License as published by
6 ;;; the Free Software Foundation, either version 3 of the License, or
7 ;;; (at your option) any later version.
9 ;;; This program is distributed in the hope that it will be useful,
10 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
11 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 ;;; GNU General Public License for more details.
14 ;;; You should have received a copy of the GNU General Public License
15 ;;; along with this program. If not, see <http://www.gnu.org/licenses/>.
21 (glDisable GL_DEPTH_TEST)
25 (glEnable GL_DEPTH_TEST)
31 (defun draw (&rest vertexes)
32 (begin-draw (length vertexes))
33 (draw-vertexes vertexes)
36 (defun begin-draw (number-of-points)
37 (cond ((= number-of-points 3) (glBegin GL_TRIANGLES))
38 ((= number-of-points 4) (glBegin GL_QUADS))))
40 (defun draw-vertexes (vertexes)
41 (cond ((null vertexes) nil)
42 (t (draw-vertex (car vertexes))
43 (draw-vertexes (cdr vertexes)))))
45 (defun draw-vertex (vertex &key texture-coord)
46 (cond ((consp (car vertex)) (draw-color (car vertex)) (apply #'simple-draw-vertex (cadr vertex)))
47 (t (cond (texture-coord (apply #'glTexCoord2f texture-coord)))
48 (apply #'simple-draw-vertex vertex))))
50 (defun simple-draw-vertex (x y &optional (z 0))
51 (cond ((3d-mode?) (glVertex3f x y z))
52 (t (glVertex2f x y))))
54 (defun draw-color (color)
55 (apply #'glColor3f color))
57 (defun load-texture (filename &optional (min-filter GL_LINEAR) (mag-filter GL_LINEAR))
60 (let ((image (IMG_Load filename)))
62 (let ((width (surface-w image)) (height (surface-h image))
63 (texture (car (glGenTextures 1))))
64 (glBindTexture GL_TEXTURE_2D texture)
65 (glTexImage2D GL_TEXTURE_2D 0 3 width height 0 GL_RGB GL_UNSIGNED_BYTE (surface-pixels image))
66 (glTexParameteri GL_TEXTURE_2D GL_TEXTURE_MIN_FILTER min-filter)
67 (glTexParameteri GL_TEXTURE_2D GL_TEXTURE_MAG_FILTER mag-filter)
68 (SDL_FreeSurface image)
69 (values texture width height))))))
71 (defun draw-image-function (filename)
73 (texture width height) (load-texture filename)
75 (lambda (&optional (f 1))
76 (draw-rectangle (* f width) (* f height) :texture texture))))))
78 (defun draw-quad (v1 v2 v3 v4 &key texture color)
79 (cond (texture (glBindTexture GL_TEXTURE_2D texture)
81 (draw-vertex v1 :texture-coord '(0 0))
82 (draw-vertex v2 :texture-coord '(1 0))
83 (draw-vertex v3 :texture-coord '(1 1))
84 (draw-vertex v4 :texture-coord '(0 1))
86 (t (cond (color (draw-color color)))
89 (defun draw-rectangle (width height &key texture color)
90 (let* ((w (/ width 2)) (-w (neg w)) (h (/ height 2)) (-h (neg h)))
91 (draw-quad (list -w h 0) (list w h 0) (list w -h 0) (list -w -h 0) :texture texture :color color)))
93 (defun draw-square (&key (size 1) texture color)
94 (draw-rectangle size size :texture texture :color color))
96 (defun draw-cube (&key size texture color)
97 (let ((-size (neg size)))
98 (enable :textures texture)
100 (draw-quad (list -size size size) (list size size size) (list size -size size) (list -size -size size) :texture texture :color color)
102 (draw-quad (list -size -size -size) (list size -size -size) (list size size -size) (list -size size -size) :texture texture :color color)
104 (draw-quad (list size size size) (list -size size size) (list -size size -size) (list size size -size) :texture texture :color color)
106 (draw-quad (list -size -size size) (list size -size size) (list size -size -size) (list -size -size -size) :texture texture :color color)
108 (draw-quad (list size -size -size) (list size -size size) (list size size size) (list size size -size) :texture texture :color color)
110 (draw-quad (list -size -size size) (list -size -size -size) (list -size size -size) (list -size size size) :texture texture :color color)))
112 (defun add-light (&key light position ambient (id GL_LIGHT1) (turn-on t))
114 (and light (glLightfv id GL_DIFFUSE (first light) (second light) (third light) (fourth light)))
115 (and light position (glLightfv GL_POSITION (first position) (second position) (third position) (fourth position)))
116 (and ambient (glLightfv id GL_AMBIENT (first ambient) (second ambient) (third ambient) (fourth ambient)))
117 (and turn-on (glEnable id))
120 (defun translate (x y &optional (z 0))
121 (glTranslatef x y z))
123 (defun rotate (xrot yrot &optional zrot)
124 (glRotatef xrot 1 0 0)
125 (glRotatef yrot 0 1 0)
126 (cond (zrot (glRotatef zrot 0 0 1))))
128 (defun enable (&key textures)
129 (cond (textures (glEnable GL_TEXTURE_2D))))