fp-tri.c revision 7ec3b29a 
1
2#include <stdio.h>
3#include <string.h>
4#include <stdlib.h>
5
6#ifndef WIN32
7#include <unistd.h>
8#include <signal.h>
9#endif
10
11#include <GL/glew.h>
12#include "glut_wrap.h"
13
14#include "readtex.c"
15
16
17#define TEXTURE_FILE DEMOS_DATA_DIR "bw.rgb"
18
19unsigned show_fps = 0;
20unsigned int frame_cnt = 0;
21void alarmhandler(int);
22static const char *filename = NULL;
23
24static void usage(char *name)
25{
26   fprintf(stderr, "usage: %s [ options ] shader_filename\n", name);
27#ifndef WIN32
28   fprintf(stderr, "\n" );
29   fprintf(stderr, "options:\n");
30   fprintf(stderr, "    -fps  show frames per second\n");
31#endif
32}
33
34#ifndef WIN32
35void alarmhandler (int sig)
36{
37   if (sig == SIGALRM) {
38      printf("%d frames in 5.0 seconds = %.3f FPS\n", frame_cnt,
39             frame_cnt / 5.0);
40
41      frame_cnt = 0;
42   }
43   signal(SIGALRM, alarmhandler);
44   alarm(5);
45}
46#endif
47
48static void args(int argc, char *argv[])
49{
50   GLint i;
51
52   for (i = 1; i < argc; i++) {
53      if (strcmp(argv[i], "-fps") == 0) {
54         show_fps = 1;
55      }
56      else if (i == argc - 1) {
57	 filename = argv[i];
58      }
59      else {
60	 usage(argv[0]);
61	 exit(1);
62      }
63   }
64
65   if (!filename) {
66      usage(argv[0]);
67      exit(1);
68   }
69}
70
71static void Init( void )
72{
73   GLuint Texture;
74   GLint errnum;
75   GLuint prognum;
76   char buf[50000];
77   GLuint sz;
78   FILE *f;
79
80   if ((f = fopen(filename, "r")) == NULL) {
81      fprintf(stderr, "Couldn't open %s\n", filename);
82      exit(1);
83   }
84
85   sz = fread(buf, 1, sizeof(buf), f);
86   if (!feof(f)) {
87      fprintf(stderr, "file too long\n");
88      exit(1);
89   }
90   fprintf(stderr, "%.*s\n", sz, buf);
91
92   if (!GLEW_ARB_fragment_program) {
93      printf("Error: GL_ARB_fragment_program not supported!\n");
94      exit(1);
95   }
96   printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
97
98   /* Setup the fragment program */
99   glGenProgramsARB(1, &prognum);
100   glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, prognum);
101   glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
102                      sz, (const GLubyte *)buf);
103
104   errnum = glGetError();
105   printf("glGetError = 0x%x\n", errnum);
106   if (errnum != GL_NO_ERROR) {
107      GLint errorpos;
108
109      glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorpos);
110      printf("errorpos: %d\n", errorpos);
111      printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
112             (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
113   }
114   glEnable(GL_FRAGMENT_PROGRAM_ARB);
115
116
117   /* Load texture */
118   glGenTextures(1, &Texture);
119   glBindTexture(GL_TEXTURE_2D, Texture);
120   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
121   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
122   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
123   if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
124      printf("Error: couldn't load texture image file %s\n", TEXTURE_FILE);
125      exit(1);
126   }
127
128
129   glGenTextures(1, &Texture);
130   glActiveTextureARB(GL_TEXTURE0_ARB + 1);
131   glBindTexture(GL_TEXTURE_2D, Texture);
132   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
133   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
134   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
135
136   {
137      GLubyte data[32][32];
138      int width = 32;
139      int height = 32;
140      int i;
141      int j;
142
143      for (i = 0; i < 32; i++)
144         for (j = 0; j < 32; j++)
145	 {
146	    /**
147	     ** +-----------+
148	     ** |     W     |
149	     ** |  +-----+  |
150	     ** |  |     |  |
151	     ** |  |  B  |  |
152	     ** |  |     |  |
153	     ** |  +-----+  |
154	     ** |           |
155	     ** +-----------+
156	     **/
157	    int i2 = i - height / 2;
158	    int j2 = j - width / 2;
159	    int h8 = height / 8;
160	    int w8 = width / 8;
161	    if ( -h8 <= i2 && i2 <= h8 && -w8 <= j2 && j2 <= w8 ) {
162	       data[i][j] = 0x00;
163	    } else if ( -2 * h8 <= i2 && i2 <= 2 * h8 && -2 * w8 <= j2 && j2 <= 2 * w8 ) {
164	       data[i][j] = 0x55;
165	    } else if ( -3 * h8 <= i2 && i2 <= 3 * h8 && -3 * w8 <= j2 && j2 <= 3 * w8 ) {
166	       data[i][j] = 0xaa;
167	    } else {
168	       data[i][j] = 0xff;
169	    }
170	 }
171
172      glTexImage2D( GL_TEXTURE_2D, 0,
173                    GL_ALPHA8,
174                    32, 32, 0,
175                    GL_ALPHA, GL_UNSIGNED_BYTE, data );
176   }
177
178
179   {
180      const float Ambient[4] = { 0.0, 1.0, 0.0, 0.0 };
181      const float Diffuse[4] = { 1.0, 0.0, 0.0, 0.0 };
182      const float Specular[4] = { 0.0, 0.0, 1.0, 0.0 };
183      const float Emission[4] = { 0.0, 0.0, 0.0, 1.0 };
184      glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, Ambient);
185      glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, Diffuse);
186      glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, Specular);
187      glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, Emission);
188   }
189
190   glClearColor(.1, .3, .5, 0);
191   fclose(f);
192}
193
194static void Reshape(int width, int height)
195{
196
197    glViewport(0, 0, (GLint)width, (GLint)height);
198
199    glMatrixMode(GL_PROJECTION);
200    glLoadIdentity();
201    glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
202    glMatrixMode(GL_MODELVIEW);
203}
204
205static void Key(unsigned char key, int x, int y)
206{
207
208    switch (key) {
209      case 27:
210	exit(1);
211      default:
212	break;
213    }
214
215    glutPostRedisplay();
216}
217
218static void Draw(void)
219{
220   glClear(GL_COLOR_BUFFER_BIT);
221
222   glProgramLocalParameter4fARB(GL_FRAGMENT_PROGRAM_ARB, 0, 1.0, 1.0, 0.0, 0.0);
223   glProgramLocalParameter4fARB(GL_FRAGMENT_PROGRAM_ARB, 1, 0.0, 0.0, 1.0, 1.0);
224   glBegin(GL_TRIANGLES);
225
226   glColor3f(0,0,1);
227   glTexCoord3f(1,1,0);
228   glVertex3f( 0.9, -0.9, -30.0);
229
230   glColor3f(1,0,0);
231   glTexCoord3f(1,-1,0);
232   glVertex3f( 0.9,  0.9, -30.0);
233
234   glColor3f(0,1,0);
235   glTexCoord3f(-1,0,0);
236   glVertex3f(-0.9,  0.0, -30.0);
237   glEnd();
238
239   glFlush();
240   if (show_fps) {
241      ++frame_cnt;
242      glutPostRedisplay();
243   }
244}
245
246
247int main(int argc, char **argv)
248{
249   glutInit(&argc, argv);
250   glutInitWindowPosition(0, 0);
251   glutInitWindowSize(250, 250);
252   glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE | GLUT_DEPTH);
253   args(argc, argv);
254   glutCreateWindow(filename);
255   glewInit();
256   glutReshapeFunc(Reshape);
257   glutKeyboardFunc(Key);
258   glutDisplayFunc(Draw);
259   Init();
260#ifndef WIN32
261   if (show_fps) {
262      signal(SIGALRM, alarmhandler);
263      alarm(5);
264   }
265#endif
266   glutMainLoop();
267   return 0;
268}
269