Le cube tournant en OpenGL Par Xavier Michelon

#include <GL/glut.h>
#include <stdlib.h>
#include <math.h>

#define PI 3.14159265

void affichage();
void clavier(unsigned char touche,int x,int y);
void reshape(int x,int y);
void calcTableCosSin();

int angle=45;
float Sin[360],Cos[360];
GLfloat L0pos[]={ 0.0,2.0,-1.0};
GLfloat L0dif[]={ 0.3,0.3,0.8};
GLfloat L1pos[]={ 2.0,2.0,2.0};
GLfloat L1dif[]={ 0.5,0.5,0.5};
GLfloat Mspec[]={0.5,0.5,0.5};
GLfloat Mshiny=50;

int main(int argc,char **argv)
{ 
  /* initialisation de glut et creation
     de la fenetre */
  glutInit(&argc,argv);
  glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
  glutInitWindowPosition(200,200);
  glutInitWindowSize(400,400);
  glutCreateWindow("light1");

  /* précalcul de la table des sinus et cosinus */
  calcTableCosSin();

  /* Initialisation d'OpenGL */
  glClearColor(0.0,0.0,0.0,0.0);
  glColor3f(1.0,0.0,00);
  glEnable(GL_DEPTH_TEST);

  /* Paramétrage des lumières */

  glShadeModel(GL_SMOOTH);
  glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER,GL_TRUE);
  glEnable(GL_LIGHTING);
  glEnable(GL_LIGHT0);
  glEnable(GL_LIGHT1);
  glLightfv(GL_LIGHT0,GL_DIFFUSE,L0dif);
  glLightfv(GL_LIGHT0,GL_SPECULAR,L0dif);
  glLightfv(GL_LIGHT1,GL_DIFFUSE,L1dif);
  glLightfv(GL_LIGHT1,GL_SPECULAR,L1dif); 

  /* Paramétrage du matériau */
  glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,Mspec);
  glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,Mshiny);
  
  /* Mise en place de la perspective */
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluPerspective(45.0,1.0,0.1,10.0);
  glMatrixMode(GL_MODELVIEW);
  
  /* Mise en place des fonctions de rappel */
  glutDisplayFunc(affichage);
  glutKeyboardFunc(clavier);
  glutReshapeFunc(reshape);

  /* Entree dans la boucle principale */
  glutMainLoop();
  return 0;
}



void affichage(){
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glLoadIdentity();
  gluLookAt(4.5*Cos[angle],2.0,4.5*Sin[angle],0.0,0.0,0.0,0.0,1.0,0.0);
  glLightfv(GL_LIGHT0,GL_POSITION,L0pos);
  glLightfv(GL_LIGHT1,GL_POSITION,L1pos);
  glutSolidTeapot(1.0);
  glutSwapBuffers();
}



void clavier(unsigned char touche,int x,int y)
{
   switch (touche)
    {
    case 'z' :   /* increment de l'angle de position */
      angle+=2;
      if (angle>=360)
	angle-=360;
      glutPostRedisplay();
      break;
    case 'a' :  /* decrement de l'angle de position */
      angle-=2;
      if (angle<0)
	angle+=360;
      glutPostRedisplay();
      break;
    case 'w' : /* Lampe 0 on */
      glEnable(GL_LIGHT0);
      glutPostRedisplay();
      break;
    case 'x' : /* Lampe 0 off */
      glDisable(GL_LIGHT0);
      glutPostRedisplay();
      break;
    case 'c': /* lampe 1 on */
      glEnable(GL_LIGHT1);
      glutPostRedisplay();
      break;
    case 'v': /* lampe 1 off */
      glDisable(GL_LIGHT1);
      glutPostRedisplay();
      break;
    case 'm': /* increment reflexion speculaire */
      Mspec[0]+=0.1;
      if (Mspec[0]>1)
	Mspec[0]=1;
      Mspec[1]+=0.1;
     if (Mspec[1]>1)
	Mspec[1]=1;
      Mspec[2]+=0.1;
     if (Mspec[2]>1)
       Mspec[2]=1;
     glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,Mspec);
     glutPostRedisplay();
      break;
    case 'l': /* decrement reflexion speculaire */
      Mspec[0]-=0.1;
      if (Mspec[0]<0)
	Mspec[0]=0;
      Mspec[1]-=0.1;
     if (Mspec[1]<0)
	Mspec[1]=0;
      Mspec[2]-=0.1;
     if (Mspec[2]<0)
	Mspec[2]=0;
      glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,Mspec);      
      glutPostRedisplay();
      break;
    case 'j': /* increment de la brillance */
      Mshiny-=1;
      if (Mshiny<0)
	Mshiny=0;
      glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,Mshiny);
      glutPostRedisplay();
      break;
    case 'k': /* decrement de la brillance */
      Mshiny+=1;
      if (Mshiny>128)
	Mshiny=128;
      glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,Mshiny);
      glutPostRedisplay();
      break;
     case 'q' :
      exit(0);
    }
}



void reshape(int x,int y)
{
  if (x<y)
    glViewport(0,(y-x)/2,x,x);
  else 
    glViewport((x-y)/2,0,y,y);
}



void calcTableCosSin()
{
  /* calcul du tableau des sinus et cosinus */
  int i;
  for (i=0;i<360;i++) {
    Cos[i]=cos(((float)i)/180.0*PI);
    Sin[i]=sin(((float)i)/180.0*PI);
  }
}