comparison test/testdyngles.c @ 2765:f55c87ae336b

Final merge of Google Summer of Code 2008 work... Bring SDL to iPhone and iPod Touch by Holmes Futrell, mentored by Sam Lantinga
author Sam Lantinga <slouken@libsdl.org>
date Sat, 04 Oct 2008 06:46:59 +0000
parents
children 0b6f51c29267
comparison
equal deleted inserted replaced
2764:4868c0df2e83 2765:f55c87ae336b
1 /*
2 * Small SDL example to demonstrate dynamically loading
3 * OpenGL lib and functions
4 *
5 * (FYI it was supposed to look like snow in the wind or something...)
6 *
7 * Compile with :
8 * gcc testdyngl.c `sdl-config --libs --cflags` -o testdyngl -DHAVE_OPENGL
9 *
10 * You can specify a different OpenGL lib on the command line, i.e. :
11 * ./testdyngl /usr/X11R6/lib/libGL.so.1.2
12 * or
13 * ./testdyngl /usr/lib/libGL.so.1.0.4496
14 *
15 */
16
17 #include <stdio.h>
18 #include <stdlib.h>
19
20 #include "SDL.h"
21
22 #ifdef __IPHONEOS__
23 #define HAVE_OPENGLES
24 #endif
25
26 #ifdef HAVE_OPENGLES
27
28 #include "SDL_opengles.h"
29
30 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
31 static void
32 quit(int rc)
33 {
34 SDL_Quit();
35 exit(rc);
36 }
37
38 void *
39 get_funcaddr(const char *p)
40 {
41 void *f = SDL_GL_GetProcAddress(p);
42 if (f) {
43 return f;
44 } else {
45 printf("Unable to get function pointer for %s\n", p);
46 quit(1);
47 }
48 return NULL;
49 }
50
51 typedef struct
52 {
53 //void (APIENTRY * glBegin) (GLenum);
54 //void (APIENTRY * glEnd) ();
55 //void (APIENTRY * glVertex3f) (GLfloat, GLfloat, GLfloat);
56
57 void (APIENTRY * glEnableClientState) (GLenum array);
58 void (APIENTRY * glVertexPointer) (GLint size, GLenum type,
59 GLsizei stride,
60 const GLvoid * pointer);
61 void (APIENTRY * glDrawArrays) (GLenum mode, GLint first, GLsizei count);
62
63
64 void (APIENTRY * glClearColor) (GLfloat, GLfloat, GLfloat, GLfloat);
65 void (APIENTRY * glClear) (GLbitfield);
66 void (APIENTRY * glDisable) (GLenum);
67 void (APIENTRY * glEnable) (GLenum);
68 void (APIENTRY * glColor4ub) (GLubyte, GLubyte, GLubyte, GLubyte);
69 void (APIENTRY * glPointSize) (GLfloat);
70 void (APIENTRY * glHint) (GLenum, GLenum);
71 void (APIENTRY * glBlendFunc) (GLenum, GLenum);
72 void (APIENTRY * glMatrixMode) (GLenum);
73 void (APIENTRY * glLoadIdentity) ();
74 void (APIENTRY * glOrthof) (GLfloat, GLfloat, GLfloat, GLfloat,
75 GLfloat, GLfloat);
76 void (APIENTRY * glRotatef) (GLfloat, GLfloat, GLfloat, GLfloat);
77 void (APIENTRY * glViewport) (GLint, GLint, GLsizei, GLsizei);
78 void (APIENTRY * glFogf) (GLenum, GLfloat);
79 }
80 glfuncs;
81
82 void
83 init_glfuncs(glfuncs * f)
84 {
85 f->glEnableClientState = get_funcaddr("glEnableClientState");
86 f->glVertexPointer = get_funcaddr("glVertexPointer");
87 f->glDrawArrays = get_funcaddr("glDrawArrays");
88 f->glClearColor = get_funcaddr("glClearColor");
89 f->glClear = get_funcaddr("glClear");
90 f->glDisable = get_funcaddr("glDisable");
91 f->glEnable = get_funcaddr("glEnable");
92 f->glColor4ub = get_funcaddr("glColor4ub");
93 f->glPointSize = get_funcaddr("glPointSize");
94 f->glHint = get_funcaddr("glHint");
95 f->glBlendFunc = get_funcaddr("glBlendFunc");
96 f->glMatrixMode = get_funcaddr("glMatrixMode");
97 f->glLoadIdentity = get_funcaddr("glLoadIdentity");
98 f->glOrthof = get_funcaddr("glOrthof");
99 f->glRotatef = get_funcaddr("glRotatef");
100 f->glViewport = get_funcaddr("glViewport");
101 f->glFogf = get_funcaddr("glFogf");
102 }
103
104 #define NB_PIXELS 1000
105
106 int
107 main(int argc, char *argv[])
108 {
109 glfuncs f;
110 int i;
111 SDL_Event event;
112 int done = 0;
113 GLfloat pixels[NB_PIXELS * 3];
114 const char *gl_library = NULL; /* Use the default GL library */
115
116 int video_w, video_h;
117
118 /* you may want to change these according to the platform */
119 video_w = 320;
120 video_h = 480;
121
122 if (argv[1]) {
123 gl_library = argv[1];
124 }
125
126 if (SDL_Init(SDL_INIT_VIDEO) < 0) {
127 printf("Unable to init SDL : %s\n", SDL_GetError());
128 return (1);
129 }
130
131 if (SDL_GL_LoadLibrary(gl_library) < 0) {
132 printf("Unable to dynamically open GL lib : %s\n", SDL_GetError());
133 quit(1);
134 }
135
136 if (SDL_SetVideoMode(video_h, video_w, 0, SDL_OPENGL) == NULL) {
137 printf("Unable to open video mode : %s\n", SDL_GetError());
138 quit(1);
139 }
140
141 /* Set the window manager title bar */
142 SDL_WM_SetCaption("SDL Dynamic OpenGL Loading Test", "testdyngl");
143
144 init_glfuncs(&f);
145
146 for (i = 0; i < NB_PIXELS; i++) {
147 pixels[3 * i] = rand() % 250 - 125;
148 pixels[3 * i + 1] = rand() % 250 - 125;
149 pixels[3 * i + 2] = rand() % 250 - 125;
150 }
151
152 f.glViewport(0, 0, video_w, video_h);
153
154 f.glMatrixMode(GL_PROJECTION);
155 f.glLoadIdentity();
156 f.glOrthof(-100, 100, -100, 100, -500, 500);
157
158 f.glMatrixMode(GL_MODELVIEW);
159 f.glLoadIdentity();
160
161 f.glEnable(GL_DEPTH_TEST);
162 f.glDisable(GL_TEXTURE_2D);
163 f.glEnable(GL_BLEND);
164 f.glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
165
166 f.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
167 f.glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
168
169 f.glEnable(GL_POINT_SMOOTH);
170 f.glHint(GL_POINT_SMOOTH_HINT, GL_NICEST);
171 f.glPointSize(5.0f);
172 f.glEnable(GL_FOG);
173 f.glFogf(GL_FOG_START, -500);
174 f.glFogf(GL_FOG_END, 500);
175 f.glFogf(GL_FOG_DENSITY, 0.005);
176
177 do {
178 f.glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
179
180 f.glRotatef(2.0, 1.0, 1.0, 1.0);
181 f.glRotatef(1.0, 0.0, 1.0, 1.0);
182
183 f.glColor4ub(255, 255, 255, 255);
184
185 f.glEnableClientState(GL_VERTEX_ARRAY);
186 f.glVertexPointer(3, GL_FLOAT, 0, pixels);
187 f.glDrawArrays(GL_POINTS, 0, NB_PIXELS);
188
189 SDL_GL_SwapBuffers();
190
191 while (SDL_PollEvent(&event)) {
192 if (event.type == SDL_KEYDOWN)
193 done = 1;
194 }
195
196 SDL_Delay(20);
197 }
198 while (!done);
199
200 SDL_Quit();
201 return 0;
202 }
203
204 #else /* HAVE_OPENGLES */
205
206 int
207 main(int argc, char *argv[])
208 {
209 printf("No OpenGL support on this system\n");
210 return 1;
211 }
212
213 #endif /* HAVE_OPENGLES */