Le source : TexturageSphere.cpp
/* Auteur: Nicolas JANEY */
/* nicolas.janey@univ-fcomte.fr */
/* Mars 2003 */
/* Placage de texture sur une sphere */
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <GL/glut.h>
#include <GL/gl.h>
#include <GL/glu.h>
#ifndef M_PI
#define M_PI 3.14159265358979323846264338327950288
#endif
/* Variables et constantes globales */
/* pour les angles et les couleurs utilises */
static float rx = 0.0F;
static float ry = 0.0F;
static float rz = 0.0F;
static const float blanc[] = { 1.0F,1.0F,1.0F,1.0F };
static const float jaune[] = { 1.0F,1.0F,0.0F,1.0F };
static const float rouge[] = { 1.0F,0.0F,0.0F,1.0F };
static const float vert[] = { 0.0F,1.0F,0.0F,1.0F };
static const float bleu[] = { 0.0F,0.0F,1.0F,1.0F };
static GLubyte *image;
GLubyte *makeImage(void) {
GLubyte *tab =(GLubyte *) malloc(8*8*3*sizeof(GLubyte));
GLubyte *t = tab;
for ( int i = 0 ; i < 8 ; i++ )
for ( int j = 0 ; j < 8 ; j++ ) {
t[0] = t[1] = t[2] = ( (i+j)%2 ) ? 0x00 : 0xFF;
t += 3; }
return(tab);
}
void myinit(void) {
glClearColor(0.8F,0.8F,0.8F,0.0);
glEnable(GL_DEPTH_TEST);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glDepthFunc(GL_LESS);
image = makeImage();
glPixelStorei(GL_UNPACK_ALIGNMENT,1);
glTexImage2D(GL_TEXTURE_2D,0,3,8,8,0,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);
glEnable(GL_TEXTURE_2D);
glShadeModel(GL_SMOOTH);
glEnable(GL_AUTO_NORMAL);
glEnable(GL_NORMALIZE);
}
void solidSphere(float rayon,int nlat,int nlon) {
for ( int i = 0 ; i < nlat ; i++ ) {
float a1 = -M_PI/2.0F + i*M_PI/nlat ;
float a2 = a1 + M_PI/nlat ;
float cs1 = cos(a1);
float cs2 = cos(a2);
float sn1 = sin(a1);
float sn2 = sin(a2);
float s1 =(float) i/nlat;
float s2 =(float) (i+1)/nlat;
glBegin(GL_QUAD_STRIP);
for ( int j = 0 ; j <= nlon ; j++ ) {
float a = j*2*M_PI/nlon;
float cs = cos(a);
float sn = sin(a);
float x1 = cs1*cs;
float z1 = cs1*sn;
float x2 = cs2*cs;
float z2 = cs2*sn;
float t =(float) j/nlon;
glNormal3f(x1,sn1,z1);
glTexCoord2f(s1,t);
glVertex3f(rayon*x1,rayon*sn1,rayon*z1);
glNormal3f(x2,sn2,z2);
glTexCoord2f(s2,t);
glVertex3f(rayon*x2,rayon*sn2,rayon*z2); }
glEnd(); }
}
void display(void) {
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glPushMatrix();
glRotatef(rx,1.0F,0.0F,0.0F);
glRotatef(ry,0.0F,1.0F,0.0F);
glRotatef(rz,0.0F,0.0F,1.0F);
solidSphere(3.0,18,36);
glPopMatrix();
glFlush();
glutSwapBuffers();
int error = glGetError();
if ( error != GL_NO_ERROR )
printf("Erreur OpenGL\n",error);
}
/* Fonction executee lorsqu'aucun evenement */
/* n'est en file d'attente */
void idle(void) {
rx += 0.1256F;
ry += 0.2117F;
rz += 0.1174F;
glutPostRedisplay() ;
}
/* Fonction executee lors d'un changement */
/* de la taille de la fenetre OpenGL */
void reshape(int x,int y) {
glViewport(0,0,x,y);
glMatrixMode(GL_PROJECTION) ;
glLoadIdentity() ;
gluPerspective(20.0F,(float) x/y,1.0,40.0) ;
glMatrixMode(GL_MODELVIEW) ;
glLoadIdentity() ;
gluLookAt(0.0,0.0,20.0,0.0,0.0,0.0,0.0,1.0,0.0);
}
/* Fonction executee lors de l'appui */
/* d'une touche alphanumerique du clavier */
void keyboard(unsigned char key,int x,int y) {
switch (key) {
case 0x0D :
{ static int anim = 0;
anim = !anim;
glutIdleFunc(( anim ) ? idle : NULL); }
break;
case 0x1B :
free(image);
exit(0);
break; }
}
/* Fonction executee lors de l'appui */
/* d'une touche de curseur ou d'une touche */
/* page up ou page down */
void special(int key,int x,int y) {
switch(key) {
case GLUT_KEY_UP :
rx++;
glutPostRedisplay() ;
break;
case GLUT_KEY_DOWN :
rx--;
glutPostRedisplay() ;
break;
case GLUT_KEY_LEFT :
ry++;
glutPostRedisplay() ;
break;
case GLUT_KEY_RIGHT :
ry--;
glutPostRedisplay() ;
break;
case GLUT_KEY_PAGE_UP :
rz++;
glutPostRedisplay() ;
break;
case GLUT_KEY_PAGE_DOWN :
rz--;
glutPostRedisplay() ;
break; }
}
int main(int argc,char **argv) {
glutInit(&argc,argv);
glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
glutInitWindowSize(260,260);
glutInitWindowPosition(50,50);
glutCreateWindow("Une sphere avec texture");
myinit();
glutReshapeFunc(reshape);
glutKeyboardFunc(keyboard);
glutSpecialFunc(special);
glutDisplayFunc(display);
glutMainLoop();
return(0);
}