/* * Compressed texture demo. Written by Daniel Borca. * This program is in the public domain. */ #include <stdio.h> #include <stdlib.h> #include <math.h> #include <string.h> #define GL_GLEXT_PROTOTYPES 1 #include <GL/glut.h> #include "readtex.c" /* I know, this is a hack. */ #define TEXTURE_FILE "../images/tree2.rgba" static float Rot = 0.0; static GLboolean Anim = 1; typedef struct { GLubyte *data; GLuint size; GLenum format; GLuint w, h; GLenum TC; GLubyte *cData; GLuint cSize; GLenum cFormat; } TEXTURE; static TEXTURE *Tx, t1, t2, t3; static GLboolean fxt1, dxtc, s3tc; static const char *TextureName (GLenum TC) { switch (TC) { case GL_RGB: return "RGB"; case GL_RGBA: return "RGBA"; case GL_COMPRESSED_RGB: return "COMPRESSED_RGB"; case GL_COMPRESSED_RGBA: return "COMPRESSED_RGBA"; case GL_COMPRESSED_RGB_FXT1_3DFX: return "GL_COMPRESSED_RGB_FXT1_3DFX"; case GL_COMPRESSED_RGBA_FXT1_3DFX: return "GL_COMPRESSED_RGBA_FXT1_3DFX"; case GL_COMPRESSED_RGB_S3TC_DXT1_EXT: return "GL_COMPRESSED_RGB_S3TC_DXT1_EXT"; case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT: return "GL_COMPRESSED_RGBA_S3TC_DXT1_EXT"; case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT: return "GL_COMPRESSED_RGBA_S3TC_DXT3_EXT"; case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT: return "GL_COMPRESSED_RGBA_S3TC_DXT5_EXT"; case GL_RGB_S3TC: return "GL_RGB_S3TC"; case GL_RGB4_S3TC: return "GL_RGB4_S3TC"; case GL_RGBA_S3TC: return "GL_RGBA_S3TC"; case GL_RGBA4_S3TC: return "GL_RGBA4_S3TC"; case 0: return "Invalid format"; default: return "Unknown format"; } } static void PrintString(const char *s) { while (*s) { glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s); s++; } } static void Idle( void ) { float t = glutGet(GLUT_ELAPSED_TIME) * 0.001; /* in seconds */ Rot = t * 360 / 4; /* 1 rotation per 4 seconds */ glutPostRedisplay(); } static void Display( void ) { /* draw background gradient */ glDisable(GL_TEXTURE_2D); glBegin(GL_POLYGON); glColor3f(1.0, 0.0, 0.2); glVertex2f(-1.5, -1.0); glColor3f(1.0, 0.0, 0.2); glVertex2f( 1.5, -1.0); glColor3f(0.0, 0.0, 1.0); glVertex2f( 1.5, 1.0); glColor3f(0.0, 0.0, 1.0); glVertex2f(-1.5, 1.0); glEnd(); glPushMatrix(); glRotatef(Rot, 0, 0, 1); glEnable(GL_TEXTURE_2D); glBegin(GL_POLYGON); glTexCoord2f(0, 1); glVertex2f(-1, -0.5); glTexCoord2f(1, 1); glVertex2f( 1, -0.5); glTexCoord2f(1, 0); glVertex2f( 1, 0.5); glTexCoord2f(0, 0); glVertex2f(-1, 0.5); glEnd(); glPopMatrix(); /* info */ glColor4f(1, 1, 1, 1); glRasterPos3f(-1.2, -0.7, 0); PrintString("Selected: "); PrintString(TextureName(Tx->TC)); if (Tx->cData) { char tmp[64]; glRasterPos3f(-1.2, -0.8, 0); PrintString("Internal: "); PrintString(TextureName(Tx->cFormat)); glRasterPos3f(-1.2, -0.9, 0); PrintString("Size : "); sprintf(tmp, "%d (%d%% of %d)", Tx->cSize, Tx->cSize * 100 / Tx->size, Tx->size); PrintString(tmp); } glutSwapBuffers(); } static void Reshape( int width, int height ) { glViewport( 0, 0, width, height ); glMatrixMode( GL_PROJECTION ); glLoadIdentity(); glOrtho( -1.5, 1.5, -1.0, 1.0, -1.0, 1.0 ); glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); } static void ReInit( GLenum TC, TEXTURE *Tx ) { GLint rv; if ((Tx->TC == TC) && (Tx->cData != NULL)) { glCompressedTexImage2DARB(GL_TEXTURE_2D, /* target */ 0, /* level */ Tx->cFormat, /* real format */ Tx->w, /* original width */ Tx->h, /* original height */ 0, /* border */ Tx->cSize, /* compressed size*/ Tx->cData); /* compressed data*/ } else { glTexImage2D(GL_TEXTURE_2D, /* target */ 0, /* level */ TC, /* internal format */ Tx->w, Tx->h, /* width, height */ 0, /* border */ Tx->format, /* texture format */ GL_UNSIGNED_BYTE, /* texture type */ Tx->data); /* the texture */ /* okay, now cache the compressed texture */ Tx->TC = TC; if (Tx->cData != NULL) { free(Tx->cData); Tx->cData = NULL; } glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_COMPRESSED_ARB, &rv); if (rv) { glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, (GLint *)&Tx->cFormat); glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_COMPRESSED_IMAGE_SIZE_ARB, (GLint *)&Tx->cSize); if ((Tx->cData = malloc(Tx->cSize)) != NULL) { glGetCompressedTexImageARB(GL_TEXTURE_2D, 0, Tx->cData); } } } } static void Init( void ) { /* HEIGHT * WIDTH + 1 (for trailing '\0') */ static char pattern[8 * 32 + 1] = {"\ \ MMM EEEE SSS AAA \ M M M E S S A A \ M M M EEEE SS A A \ M M M E SS AAAAA \ M M E S S A A \ M M EEEE SSS A A \ " }; GLuint i, j; GLubyte (*texture1)[8 * 32][4]; GLubyte (*texture2)[256][256][4]; t1.w = 32; t1.h = 8; t1.size = t1.w * t1.h * 4; t1.data = malloc(t1.size); t1.format = GL_RGBA; t1.TC = GL_RGBA; texture1 = (GLubyte (*)[8 * 32][4])t1.data; for (i = 0; i < sizeof(pattern) - 1; i++) { switch (pattern[i]) { default: case ' ': (*texture1)[i][0] = 255; (*texture1)[i][1] = 255; (*texture1)[i][2] = 255; (*texture1)[i][3] = 64; break; case 'M': (*texture1)[i][0] = 255; (*texture1)[i][1] = 0; (*texture1)[i][2] = 0; (*texture1)[i][3] = 255; break; case 'E': (*texture1)[i][0] = 0; (*texture1)[i][1] = 255; (*texture1)[i][2] = 0; (*texture1)[i][3] = 255; break; case 'S': (*texture1)[i][0] = 0; (*texture1)[i][1] = 0; (*texture1)[i][2] = 255; (*texture1)[i][3] = 255; break; case 'A': (*texture1)[i][0] = 255; (*texture1)[i][1] = 255; (*texture1)[i][2] = 0; (*texture1)[i][3] = 255; break; } } t2.w = 256; t2.h = 256; t2.size = t2.w * t2.h * 4; t2.data = malloc(t2.size); t2.format = GL_RGBA; t2.TC = GL_RGBA; texture2 = (GLubyte (*)[256][256][4])t2.data; for (j = 0; j < t2.h; j++) { for (i = 0; i < t2.w; i++) { (*texture2)[j][i][0] = sqrt(i * j * 255 * 255 / (t2.w * t2.h)); (*texture2)[j][i][1] = 0; (*texture2)[j][i][2] = 0; (*texture2)[j][i][3] = 255; } } t3.data = LoadRGBImage(TEXTURE_FILE, (GLint *)&t3.w, (GLint *)&t3.h, &t3.format); t3.size = t3.w * t3.h * ((t3.format == GL_RGB) ? 3 : 4); t3.TC = GL_RGBA; ReInit(GL_RGBA, Tx = &t1); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); glEnable(GL_TEXTURE_2D); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); } static void Key( unsigned char key, int x, int y ) { (void) x; (void) y; switch (key) { case 27: exit(0); break; case ' ': Anim = !Anim; if (Anim) glutIdleFunc( Idle ); else glutIdleFunc( NULL ); break; case 't': if (Tx == &t1) { Tx = &t2; } else if (Tx == &t2) { Tx = &t3; } else { Tx = &t1; } ReInit(Tx->TC, Tx); break; case '9': ReInit(GL_RGB, Tx); break; case '0': ReInit(GL_RGBA, Tx); break; case '1': ReInit(GL_COMPRESSED_RGB, Tx); break; case '2': ReInit(GL_COMPRESSED_RGBA, Tx); break; case '3': if (fxt1) ReInit(GL_COMPRESSED_RGB_FXT1_3DFX, Tx); break; case '4': if (fxt1) ReInit(GL_COMPRESSED_RGBA_FXT1_3DFX, Tx); break; case '5': if (dxtc) ReInit(GL_COMPRESSED_RGB_S3TC_DXT1_EXT, Tx); break; case '6': if (dxtc) ReInit(GL_COMPRESSED_RGBA_S3TC_DXT1_EXT, Tx); break; case '7': if (dxtc) ReInit(GL_COMPRESSED_RGBA_S3TC_DXT3_EXT, Tx); break; case '8': if (dxtc) ReInit(GL_COMPRESSED_RGBA_S3TC_DXT5_EXT, Tx); break; case 'a': if (s3tc) ReInit(GL_RGB_S3TC, Tx); break; case 's': if (s3tc) ReInit(GL_RGB4_S3TC, Tx); break; case 'd': if (s3tc) ReInit(GL_RGBA_S3TC, Tx); break; case 'f': if (s3tc) ReInit(GL_RGBA4_S3TC, Tx); break; } glutPostRedisplay(); } int main( int argc, char *argv[] ) { float gl_version; GLint num_formats; GLint i; GLint formats[64]; glutInit( &argc, argv ); glutInitWindowPosition( 0, 0 ); glutInitWindowSize( 400, 300 ); glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE ); if (glutCreateWindow(argv[0]) <= 0) { printf("Couldn't create window\n"); exit(0); } gl_version = atof( (const char *) glGetString( GL_VERSION ) ); if ( (gl_version < 1.3) && !glutExtensionSupported("GL_ARB_texture_compression") ) { printf("Sorry, GL_ARB_texture_compression not supported\n"); exit(0); } if (glutExtensionSupported("GL_3DFX_texture_compression_FXT1")) { fxt1 = GL_TRUE; } if (glutExtensionSupported("GL_EXT_texture_compression_s3tc")) { dxtc = GL_TRUE; } if (glutExtensionSupported("GL_S3_s3tc")) { s3tc = GL_TRUE; } glGetIntegerv( GL_NUM_COMPRESSED_TEXTURE_FORMATS_ARB, & num_formats ); (void) memset( formats, 0, sizeof( formats ) ); glGetIntegerv( GL_COMPRESSED_TEXTURE_FORMATS_ARB, formats ); printf( "The following texture formats are supported:\n" ); for ( i = 0 ; i < num_formats ; i++ ) { printf( "\t%s\n", TextureName( formats[i] ) ); } Init(); glutReshapeFunc( Reshape ); glutKeyboardFunc( Key ); glutDisplayFunc( Display ); if (Anim) glutIdleFunc( Idle ); glutMainLoop(); return 0; }