progs/fp/tri-tex.c

   1 /*
   2  * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and
   5  * its documentation for any purpose is hereby granted without fee, provided
   6  * that (i) the above copyright notices and this permission notice appear in
   7  * all copies of the software and related documentation, and (ii) the name of
   8  * Silicon Graphics may not be used in any advertising or
   9  * publicity relating to the software without the specific, prior written
  10  * permission of Silicon Graphics.
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
  13  * ANY KIND,
  14  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
  15  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
  16  *
  17  * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
  18  * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
  19  * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
  20  * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
  21  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  22  * OF THIS SOFTWARE.
  23  */
  24
  25 #include <assert.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <stdlib.h>
  29 #define GL_GLEXT_PROTOTYPES
  30 #include <GL/glut.h>
  31
  32 #include "readtex.c"
  33
  34
  35 #define TEXTURE_FILE "../images/girl.rgb"
  36
  37
  38 GLenum doubleBuffer;
  39
  40 static void Init( void )
  41 {
  42    static const char *modulate2D =
  43       "!!ARBfp1.0\n"
  44       "TEX result.color, fragment.color, texture[0], 2D; \n"
  45       "END"
  46       ;
  47    GLuint modulateProg;
  48    GLuint Texture;
  49
  50    if (!glutExtensionSupported("GL_ARB_fragment_program")) {
  51       printf("Error: GL_ARB_fragment_program not supported!\n");
  52       exit(1);
  53    }
  54    printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
  55
  56    /* Setup the fragment program */
  57    glGenProgramsARB(1, &modulateProg);
  58    glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, modulateProg);
  59    glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
  60                         strlen(modulate2D), (const GLubyte *)modulate2D);
  61
  62    printf("glGetError = 0x%x\n", (int) glGetError());
  63    printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
  64           (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
  65    assert(glIsProgramARB(modulateProg));
  66
  67    glEnable(GL_FRAGMENT_PROGRAM_ARB);
  68
  69    /* Load texture */
  70    glGenTextures(1, &Texture);
  71    glBindTexture(GL_TEXTURE_2D, Texture);
  72    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  73    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  74    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  75    if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
  76       printf("Error: couldn't load texture image file %s\n", TEXTURE_FILE);
  77       exit(1);
  78    }
  79    /* XXX this enable shouldn't really be needed!!! */
  80    glEnable(GL_TEXTURE_2D);
  81
  82    glClearColor(.3, .3, .3, 0);
  83 }
  84
  85 static void Reshape(int width, int height)
  86 {
  87
  88     glViewport(0, 0, (GLint)width, (GLint)height);
  89
  90     glMatrixMode(GL_PROJECTION);
  91     glLoadIdentity();
  92     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  93     glMatrixMode(GL_MODELVIEW);
  94 }
  95
  96 static void Key(unsigned char key, int x, int y)
  97 {
  98
  99     switch (key) {
 100       case 27:
 101         exit(1);
 102       default:
 103         return;
 104     }
 105
 106     glutPostRedisplay();
 107 }
 108
 109 static void Draw(void)
 110 {
 111    glClear(GL_COLOR_BUFFER_BIT);
 112
 113    glBegin(GL_TRIANGLES);
 114    glColor3f(0,0,1);
 115 /*    glTexCoord2f(1, 0); */
 116    glVertex3f( 0.9, -0.9, -30.0);
 117    glColor3f(1,0,0);
 118 /*    glTexCoord2f(1, 1); */
 119    glVertex3f( 0.9,  0.9, -30.0);
 120    glColor3f(0,1,0);
 121 /*    glTexCoord2f(0, .5); */
 122    glVertex3f(-0.9,  0.0, -30.0);
 123    glEnd();
 124
 125    glFlush();
 126
 127    if (doubleBuffer) {
 128       glutSwapBuffers();
 129    }
 130 }
 131
 132 static GLenum Args(int argc, char **argv)
 133 {
 134     GLint i;
 135
 136     doubleBuffer = GL_FALSE;
 137
 138     for (i = 1; i < argc; i++) {
 139         if (strcmp(argv[i], "-sb") == 0) {
 140             doubleBuffer = GL_FALSE;
 141         } else if (strcmp(argv[i], "-db") == 0) {
 142             doubleBuffer = GL_TRUE;
 143         } else {
 144             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 145             return GL_FALSE;
 146         }
 147     }
 148     return GL_TRUE;
 149 }
 150
 151 int main(int argc, char **argv)
 152 {
 153     GLenum type;
 154
 155     glutInit(&argc, argv);
 156
 157     if (Args(argc, argv) == GL_FALSE) {
 158         exit(1);
 159     }
 160
 161     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 162
 163     type = GLUT_RGB;
 164     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 165     glutInitDisplayMode(type);
 166
 167     if (glutCreateWindow("First Tri") == GL_FALSE) {
 168         exit(1);
 169     }
 170
 171     Init();
 172
 173     glutReshapeFunc(Reshape);
 174     glutKeyboardFunc(Key);
 175     glutDisplayFunc(Draw);
 176     glutMainLoop();
 177         return 0;
 178 }