L'exécutable

• une sphère blanche éclairée par deux spots rouge et vert
• 1 et 7, 2 et 8 pour jouer sur la focalisation des spots
• t et T pour jouer sur la facettisation de la sphère
• s et S pour jouer sur la réflexivité de la sphère

Le source: Spot.cpp

#include <windows.h>

#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glaux.h>
#include <GL/glut.h>

#include <stdio.h>

static float anglex = 0.0F ;
static float angley = 0.0F ;
static GLfloat shininess = 100.0F ;
static int nf = 128 ;
static float o0 = 10.0F ;
static float o1 = 10.0F ;
  
void myinit(void) {
  GLfloat rouge[] = { 1.0F,0.0F,0.0F,1.0F };
  GLfloat specular[] = { 0.0F,0.0F,0.0F,1.0F };
  GLfloat bleu[] = { 0.0F,0.0F,1.0F,1.0F };
  GLfloat vert[] = { 0.0F,1.0F,0.0F,1.0F };
  GLfloat l_pos0[] = { 1.0F,0.0F,2.0F,1.0F };
  GLfloat l_dir0[] = { -1.0F,0.0F,-2.0F,1.0F };
  GLfloat l_pos1[] = { -1.0F,0.0F,2.0F,1.0F };
  GLfloat l_dir1[] = { 1.0F,0.0F,-2.0F,1.0F };
  glClearColor(0.5F,0.5F,1.0F,1.0F) ;
  glMaterialfv(GL_FRONT,GL_SPECULAR,specular);
  glLightfv(GL_LIGHT0,GL_DIFFUSE,rouge);
  glLightfv(GL_LIGHT0,GL_POSITION,l_pos0);
  glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,l_dir0);
  glLightfv(GL_LIGHT1,GL_DIFFUSE,vert);
  glLightfv(GL_LIGHT1,GL_POSITION,l_pos1);
  glLightfv(GL_LIGHT1,GL_SPOT_DIRECTION,l_dir1);
  glEnable(GL_LIGHTING);
  glEnable(GL_LIGHT0);
  glEnable(GL_LIGHT1);
  glDepthFunc(GL_LESS);
  glEnable(GL_DEPTH_TEST);
}

void CALLBACK display(void) {
  glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  glPushMatrix();
  glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,o0);
  glLightf(GL_LIGHT1,GL_SPOT_CUTOFF,o1);
  glRotatef(angley,0.0F,1.0F,0.0F) ;
  glRotatef(anglex,1.0F,0.0F,0.0F) ;
  glMaterialf(GL_FRONT,GL_SHININESS,shininess);
  glutSolidSphere(1.0,nf,nf);
  printf("Nombre de facettes %d\n",nf*nf) ;
  glPopMatrix();
  glFlush();
  auxSwapBuffers();
}

void CALLBACK myReshape(int w,int h) {
  glViewport(0,0,w,h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  if (w <= h)
    glOrtho(-1.5,1.5,-1.5*(float)h/(float)w,1.5*(float)h/(float)w,-10.,10.);
    else
    glOrtho(-1.5*(float)w/(float)h,1.5*(float)w/(float)h,-1.5,1.5,-10.,10.);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
}

void CALLBACK up(void) {
  anglex-- ;
}

void CALLBACK down(void) {
  anglex++ ;
}

void CALLBACK left(void) {
  angley-- ;
}

void CALLBACK right(void) {
  angley++ ;
}

void CALLBACK keys(void) {
  shininess *= 1.03F ;
}

void CALLBACK keyS(void) {
  shininess /= 1.03F ;
}

void CALLBACK key1(void) {
  o1 *= 1.1F ;
}

void CALLBACK key7(void) {
  o1 /= 1.1F ;
}

void CALLBACK key2(void) {
  o0 *= 1.1F ;
}

void CALLBACK key8(void) {
  o0 /= 1.1F ;
}

void CALLBACK keyt(void) {
  nf *= 2 ;
}

void CALLBACK keyT(void) {
  nf /= 2 ;
  if ( nf == 2 )
    nf = 4 ;
}

void main(void) {
  auxInitDisplayMode(AUX_DOUBLE|AUX_RGB|AUX_DEPTH);
  auxInitPosition(0,0,250,250);
  auxInitWindow("2 spots lumineux");
  myinit();
  auxKeyFunc(AUX_UP,up) ;
  auxKeyFunc(AUX_DOWN,down) ;
  auxKeyFunc(AUX_LEFT,left) ;
  auxKeyFunc(AUX_RIGHT,right) ;
  auxKeyFunc(AUX_s,keys) ;
  auxKeyFunc(AUX_S,keyS) ;
  auxKeyFunc(AUX_t,keyt) ;
  auxKeyFunc(AUX_T,keyT) ;
  auxKeyFunc(AUX_1,key1) ;
  auxKeyFunc(AUX_7,key7) ;
  auxKeyFunc(AUX_2,key2) ;
  auxKeyFunc(AUX_8,key8) ;
  auxReshapeFunc(myReshape);
  auxMainLoop(display);
}

 RETOUR