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-rw-r--r-- | progs/demos/cubemap.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/progs/demos/cubemap.c b/progs/demos/cubemap.c new file mode 100644 index 00000000000..620a2d65330 --- /dev/null +++ b/progs/demos/cubemap.c @@ -0,0 +1,246 @@ +/* $Id: cubemap.c,v 1.1 2000/05/30 01:18:29 brianp Exp $ */ + +/* + * GL_ARB_texture_cube_map demo + * + * Brian Paul + * May 2000 + * + * + * Copyright (C) 2000 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + + +/* + * This is a pretty minimalistic demo for now. Eventually, use some + * interesting cube map textures and 3D objects. + * For now, we use 6 checkerboard "walls" and a sphere (good for + * verification purposes). + */ + + +#include <math.h> +#include <stdlib.h> +#include <string.h> +#include "GL/glut.h" + +static GLfloat Xrot = 0, Yrot = 0; + + +static void draw( void ) +{ + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + glMatrixMode(GL_TEXTURE); + glLoadIdentity(); + glRotatef(Xrot, 1, 0, 0); + glRotatef(Yrot, 0, 1, 0); + glutSolidSphere(2.0, 20, 20); + glMatrixMode(GL_MODELVIEW); + + glutSwapBuffers(); +} + + +static void idle(void) +{ + Yrot += 5.0; + glutPostRedisplay(); +} + + +static void set_mode(GLuint mode) +{ + if (mode == 0) { + glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP_ARB); + glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP_ARB); + glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP_ARB); + printf("GL_REFLECTION_MAP_ARB mode\n"); + } + else if (mode == 1) { + glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_NORMAL_MAP_ARB); + glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_NORMAL_MAP_ARB); + glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_NORMAL_MAP_ARB); + printf("GL_NORMAL_MAP_ARB mode\n"); + } + glEnable(GL_TEXTURE_GEN_S); + glEnable(GL_TEXTURE_GEN_T); + glEnable(GL_TEXTURE_GEN_R); +} + + +static void key(unsigned char k, int x, int y) +{ + static GLboolean anim = GL_TRUE; + static GLuint mode = 0; + (void) x; + (void) y; + switch (k) { + case ' ': + anim = !anim; + if (anim) + glutIdleFunc(idle); + else + glutIdleFunc(NULL); + break; + case 'm': + mode = !mode; + set_mode(mode); + break; + case 27: + exit(0); + } + glutPostRedisplay(); +} + + +static void specialkey(int key, int x, int y) +{ + GLfloat step = 10; + (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(); +} + + +/* new window size or exposure */ +static void reshape(int width, int height) +{ + glViewport(0, 0, (GLint)width, (GLint)height); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glFrustum( -2.0, 2.0, -2.0, 2.0, 6.0, 20.0 ); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef( 0.0, 0.0, -8.0 ); +} + + +static void init( void ) +{ +#define CUBE_TEX_SIZE 64 + GLubyte image[CUBE_TEX_SIZE][CUBE_TEX_SIZE][3]; + static const GLubyte colors[6][3] = { + { 255, 0, 0 }, + { 0, 255, 255 }, + { 0, 255, 0 }, + { 255, 0, 255 }, + { 0, 0, 255 }, + { 255, 255, 0 } + }; + static const GLenum targets[6] = { + GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB, + GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB, + GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB, + GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB, + GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB, + GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB + }; + + GLint i, j, f; + + /* check for extension */ + { + char *exten = (char *) glGetString(GL_EXTENSIONS); + if (!strstr(exten, "GL_ARB_texture_cube_map")) { + printf("Sorry, this demo requires GL_ARB_texture_cube_map\n"); + exit(0); + } + } + + + glPixelStorei(GL_UNPACK_ALIGNMENT, 1); + + /* make colored checkerboard cube faces */ + for (f = 0; f < 6; f++) { + for (i = 0; i < CUBE_TEX_SIZE; i++) { + for (j = 0; j < CUBE_TEX_SIZE; j++) { + if ((i/4 + j/4) & 1) { + image[i][j][0] = colors[f][0]; + image[i][j][1] = colors[f][1]; + image[i][j][2] = colors[f][2]; + } + else { + image[i][j][0] = 255; + image[i][j][1] = 255; + image[i][j][2] = 255; + } + } + } + + glTexImage2D(targets[f], 0, GL_RGB, CUBE_TEX_SIZE, CUBE_TEX_SIZE, 0, + GL_RGB, GL_UNSIGNED_BYTE, image); + } + + /* + glTexParameteri(GL_TEXTURE_CUBE_MAP_ARB, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_CUBE_MAP_ARB, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + */ + glTexParameteri(GL_TEXTURE_CUBE_MAP_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST); + glTexParameteri(GL_TEXTURE_CUBE_MAP_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST); + + glEnable(GL_TEXTURE_CUBE_MAP_ARB); + + glClearColor(.3, .3, .3, 0); + glColor3f( 1.0, 1.0, 1.0 ); + + set_mode(0); +} + + +static void usage(void) +{ + printf("keys:\n"); + printf(" SPACE - toggle animation\n"); + printf(" CURSOR KEYS - rotation\n"); + printf(" m - toggle texgen reflection mode\n"); +} + + +int main( int argc, char *argv[] ) +{ + glutInitWindowPosition(0, 0); + glutInitWindowSize(300, 300); + glutInitDisplayMode( GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE ); + glutCreateWindow("Texture Cube Maping"); + init(); + glutReshapeFunc( reshape ); + glutKeyboardFunc( key ); + glutSpecialFunc( specialkey ); + glutIdleFunc( idle ); + glutDisplayFunc( draw ); + usage(); + glutMainLoop(); + return 0; +} |