/* * GL_ARB_multitexture demo * * Command line options: * -info print GL implementation information * * * Brian Paul November 1998 This program is in the public domain. * Modified on 12 Feb 2002 for > 2 texture units. */ #include <math.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <GL/glew.h> #include <GL/glut.h> #include "readtex.h" #define TEXTURE_1_FILE "../images/girl.rgb" #define TEXTURE_2_FILE "../images/reflect.rgb" #define TEX0 1 #define TEX7 8 #define ANIMATE 10 #define QUIT 100 static GLboolean Animate = GL_TRUE; static GLint NumUnits = 1; static GLboolean TexEnabled[8]; static GLfloat Drift = 0.0; static GLfloat Xrot = 20.0, Yrot = 30.0, Zrot = 0.0; static void Idle( void ) { if (Animate) { GLint i; Drift = glutGet(GLUT_ELAPSED_TIME) * 0.001; for (i = 0; i < NumUnits; i++) { glActiveTextureARB(GL_TEXTURE0_ARB + i); glMatrixMode(GL_TEXTURE); glLoadIdentity(); if (i == 0) { glTranslatef(Drift, 0.0, 0.0); glScalef(2, 2, 1); } else if (i == 1) { glTranslatef(0.0, Drift, 0.0); } else { float tx = 0.5, ty = 0.5; glTranslatef(tx, ty, 0.0); glRotatef(180.0 * Drift, 0, 0, 1); glScalef(1.0/i, 1.0/i, 1.0/i); glTranslatef(-tx, -ty + i * 0.1, 0.0); } } glMatrixMode(GL_MODELVIEW); glutPostRedisplay(); } } static void DrawObject(void) { static const GLfloat tex_coords[] = { 0.0, 0.0, 1.0, 1.0, 0.0 }; static const GLfloat vtx_coords[] = { -1.0, -1.0, 1.0, 1.0, -1.0 }; GLint i, j; if (!TexEnabled[0] && !TexEnabled[1]) glColor3f(0.1, 0.1, 0.1); /* add onto this */ else glColor3f(1, 1, 1); /* modulate this */ glBegin(GL_QUADS); for (j = 0; j < 4; j++ ) { for (i = 0; i < NumUnits; i++) { if (TexEnabled[i]) glMultiTexCoord2fARB(GL_TEXTURE0_ARB + i, tex_coords[j], tex_coords[j+1]); } glVertex2f( vtx_coords[j], vtx_coords[j+1] ); } glEnd(); } static void Display( void ) { glClear( GL_COLOR_BUFFER_BIT ); glPushMatrix(); glRotatef(Xrot, 1.0, 0.0, 0.0); glRotatef(Yrot, 0.0, 1.0, 0.0); glRotatef(Zrot, 0.0, 0.0, 1.0); glScalef(5.0, 5.0, 5.0); DrawObject(); glPopMatrix(); glutSwapBuffers(); } static void Reshape( int width, int height ) { glViewport( 0, 0, width, height ); glMatrixMode( GL_PROJECTION ); glLoadIdentity(); glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 100.0 ); /*glOrtho( -6.0, 6.0, -6.0, 6.0, 10.0, 100.0 );*/ glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); glTranslatef( 0.0, 0.0, -70.0 ); } static void ToggleUnit(int unit) { TexEnabled[unit] = !TexEnabled[unit]; glActiveTextureARB(GL_TEXTURE0_ARB + unit); if (TexEnabled[unit]) glEnable(GL_TEXTURE_2D); else glDisable(GL_TEXTURE_2D); printf("Enabled: "); for (unit = 0; unit < NumUnits; unit++) printf("%d ", (int) TexEnabled[unit]); printf("\n"); } static void ModeMenu(int entry) { if (entry >= TEX0 && entry <= TEX7) { /* toggle */ GLint i = entry - TEX0; ToggleUnit(i); } else if (entry==ANIMATE) { Animate = !Animate; if (Animate) glutIdleFunc(Idle); else glutIdleFunc(NULL); } else if (entry==QUIT) { exit(0); } glutPostRedisplay(); } static void Key( unsigned char key, int x, int y ) { (void) x; (void) y; switch (key) { case 'a': Animate = !Animate; break; case '0': ToggleUnit(0); break; case '1': ToggleUnit(1); break; case '2': ToggleUnit(2); break; case '3': ToggleUnit(3); break; case '4': ToggleUnit(4); break; case '5': ToggleUnit(5); break; case '6': ToggleUnit(6); break; case '7': ToggleUnit(7); break; case 27: exit(0); break; } glutPostRedisplay(); } static void SpecialKey( int key, int x, int y ) { float step = 3.0; (void) x; (void) y; switch (key) { case GLUT_KEY_UP: Xrot += step; break; case GLUT_KEY_DOWN: Xrot -= step; break; case GLUT_KEY_LEFT: Yrot += step; break; case GLUT_KEY_RIGHT: Yrot -= step; break; } glutPostRedisplay(); } static void Init( int argc, char *argv[] ) { GLuint texObj[8]; GLint size, i; const char *exten = (const char *) glGetString(GL_EXTENSIONS); if (!strstr(exten, "GL_ARB_multitexture")) { printf("Sorry, GL_ARB_multitexture not supported by this renderer.\n"); exit(1); } glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &NumUnits); printf("%d texture units supported\n", NumUnits); if (NumUnits > 8) NumUnits = 8; glGetIntegerv(GL_MAX_TEXTURE_SIZE, &size); printf("%d x %d max texture size\n", size, size); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); for (i = 0; i < NumUnits; i++) { if (i < 2) TexEnabled[i] = GL_TRUE; else TexEnabled[i] = GL_FALSE; } /* allocate two texture objects */ glGenTextures(NumUnits, texObj); /* setup the texture objects */ for (i = 0; i < NumUnits; i++) { glActiveTextureARB(GL_TEXTURE0_ARB + i); glBindTexture(GL_TEXTURE_2D, texObj[i]); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); if (i == 0) { if (!LoadRGBMipmaps(TEXTURE_1_FILE, GL_RGB)) { printf("Error: couldn't load texture image\n"); exit(1); } } else if (i == 1) { if (!LoadRGBMipmaps(TEXTURE_2_FILE, GL_RGB)) { printf("Error: couldn't load texture image\n"); exit(1); } } else { /* checker */ GLubyte image[8][8][3]; GLint i, j; for (i = 0; i < 8; i++) { for (j = 0; j < 8; j++) { if ((i + j) & 1) { image[i][j][0] = 50; image[i][j][1] = 50; image[i][j][2] = 50; } else { image[i][j][0] = 25; image[i][j][1] = 25; image[i][j][2] = 25; } } } glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 8, 8, 0, GL_RGB, GL_UNSIGNED_BYTE, (GLvoid *) image); } /* Bind texObj[i] to ith texture unit */ if (i < 2) glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); else glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_ADD); if (TexEnabled[i]) glEnable(GL_TEXTURE_2D); } glShadeModel(GL_FLAT); glClearColor(0.3, 0.3, 0.4, 1.0); if (argc > 1 && strcmp(argv[1], "-info")==0) { printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER)); printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION)); printf("GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR)); printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS)); } } int main( int argc, char *argv[] ) { GLint i; glutInit( &argc, argv ); glutInitWindowSize( 300, 300 ); glutInitWindowPosition( 0, 0 ); glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE ); glutCreateWindow(argv[0] ); glewInit(); Init( argc, argv ); glutReshapeFunc( Reshape ); glutKeyboardFunc( Key ); glutSpecialFunc( SpecialKey ); glutDisplayFunc( Display ); if (Animate) glutIdleFunc(Idle); glutCreateMenu(ModeMenu); for (i = 0; i < NumUnits; i++) { char s[100]; sprintf(s, "Toggle Texture %d", i); glutAddMenuEntry(s, TEX0 + i); } glutAddMenuEntry("Toggle Animation", ANIMATE); glutAddMenuEntry("Quit", QUIT); glutAttachMenu(GLUT_RIGHT_BUTTON); glutMainLoop(); return 0; }