/* teatex.c  */

/* E. Angel, Interactive Computer Graphics */
/* A Top-Down Approach with OpenGL, Third Edition */
/* Addison-Wesley Longman, 2003 */

/* Utah teapot with texture map  */
#include <stdlib.h>#include <GL/glut.h>GLfloat planes[]= {-1.0, 0.0, 1.0, 0.0};GLfloat planet[]= {0.0, -1.0,  0.0, 1.0};	GLfloat vertices[][3] = {{-1.0,-1.0,-1.0},{1.0,-1.0,-1.0},	{1.0,1.0,-1.0}, {-1.0,1.0,-1.0}, {-1.0,-1.0,1.0}, 	{1.0,-1.0,1.0}, {1.0,1.0,1.0}, {-1.0,1.0,1.0}};	GLfloat colors[][4] = {{0.0,0.0,0.0,0.5},{1.0,0.0,0.0,0.5},	{1.0,1.0,0.0,0.5}, {0.0,1.0,0.0,0.5}, {0.0,0.0,1.0,0.5}, 	{1.0,0.0,1.0,0.5}, {1.0,1.0,1.0,0.5}, {0.0,1.0,1.0,0.5}};void polygon(int a, int b, int c , int d){/* draw a polygon via list of vertices */ 	glBegin(GL_POLYGON);		glVertex3fv(vertices[a]);		glVertex3fv(vertices[b]);		glVertex3fv(vertices[c]);		glVertex3fv(vertices[d]);	glEnd();																										}static GLfloat theta[] = {0.0,0.0,0.0};static GLint axis = 2;void display(void){/* display callback, clear frame buffer and z buffer,   rotate cube and draw, swap buffers */ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	glLoadIdentity();	glRotatef(theta[0], 1.0, 0.0, 0.0);	glRotatef(theta[1], 0.0, 1.0, 0.0);	glRotatef(theta[2], 0.0, 0.0, 1.0);	glutSolidTeapot(1.0);	glutSwapBuffers();}void spinTeapot(){/* Idle callback, spin cube 2 degrees about selected axis */	theta[axis] += 2.0;	if( theta[axis] > 360.0 ) theta[axis] -= 360.0;	glutPostRedisplay();}void mouse(int btn, int state, int x, int y){/* mouse callback, selects an axis about which to rotate */	if(btn==GLUT_LEFT_BUTTON && state == GLUT_DOWN) axis = 0;	if(btn==GLUT_MIDDLE_BUTTON && state == GLUT_DOWN) axis = 1;	if(btn==GLUT_RIGHT_BUTTON && state == GLUT_DOWN) axis = 2;}void myReshape(int w, int h){    glViewport(0, 0, w, h);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    if (w <= h)        glOrtho(-2.0, 2.0, -2.0 * (GLfloat) h / (GLfloat) w,            2.0 * (GLfloat) h / (GLfloat) w, -10.0, 10.0);    else        glOrtho(-2.0 * (GLfloat) w / (GLfloat) h,            2.0 * (GLfloat) w / (GLfloat) h, -2.0, 2.0, -10.0, 10.0);    glMatrixMode(GL_MODELVIEW);}void key(char k, int x, int y){	if(k == '1') glutIdleFunc(spinTeapot);	if(k == '2') glutIdleFunc(NULL);}voidmain(int argc, char **argv){   GLubyte image[64][64][3];   int i, j, r, c;   for(i=0;i<64;i++)   {     for(j=0;j<64;j++)     {       c = ((((i&0x8)==0)^((j&0x8))==0))*255;       image[i][j][0]= (GLubyte) c;       image[i][j][1]= (GLubyte) c;       image[i][j][2]= (GLubyte) c;     }   }    glutInit(&argc, argv);    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);    glutInitWindowSize(500, 500);    glutCreateWindow("colorcube");/* need both double buffering and z buffer */    glutReshapeFunc(myReshape);    glutDisplayFunc(display);   glutIdleFunc(spinTeapot);   glutMouseFunc(mouse); glEnable(GL_DEPTH_TEST);   glEnable(GL_TEXTURE_2D);   glTexImage2D(GL_TEXTURE_2D,0,3,64,64,0,GL_RGB,GL_UNSIGNED_BYTE, image);   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST); 	glutKeyboardFunc(key);	glClearColor(1.0,1.0,1.0,1.0);    glutMainLoop();}