/* Cylindre modelise par facettes               */
/* avec materiel et eclairage                   */
/*                                              */
/* Auteur: Nicolas JANEY                        */
/* nicolas.janey@univ-fcomte.fr                 */
/* Octobre 2010                                 */

#include <stdlib.h>
#include <stdio.h>
#include <math.h>

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

/* Variables et constantes globales             */
/* pour les angles et les couleurs utilises     */

#ifndef M_PI
#define M_PI 3.14159
#endif

static int scn = 0;
static float rx = 0.0F;
static float ry = 0.0F;
static float rz = 0.0F;
static float p = 2.0F;
static float r = 0.0F;
static float ouv = 10.0F;
static const float noir[] = { 0.0F,0.0F,0.0F,1.0F };
static const float grisClair[] = { 0.7F,0.7F,0.7F,1.0F };
static const float grisFonce[] = { 0.3F,0.3F,0.3F,1.0F };
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 const float bleuatre[] = { 0.4F,0.4F,1.0F,1.0F };
static const float jaunatre[] = { 0.6F,0.6F,0.0F,1.0F };
static const float jauneClair[] = { 1.0F,1.0F,0.7F,1.0F };
static int n = 72;
static int m = 72;

/* Fonction d'initialisation des parametres     */
/* OpenGL ne changeant pas au cours de la vie   */
/* du programme                                 */

void init(void) {
  glDepthFunc(GL_LESS);
  glEnable(GL_DEPTH_TEST);
  glEnable(GL_NORMALIZE);
  glEnable(GL_AUTO_NORMAL);
  glEnable(GL_LIGHTING);
}

/* Scene dessinee                               */

void mySolidCylinder(int n,int m) {
  glPushMatrix();
  for ( int j = 0 ; j < m ; j++ ) {
    float hi = 1.0F-j*2.0F/m;
    float hf = hi-2.0F/m;
    glBegin(GL_QUAD_STRIP);
    for( int i = 0 ; i <= n ; i++ ){
      float a = (2*M_PI*i)/n;
      float sn = -sin(a);
      float cs = cos(a);
      glNormal3f(cs,0.0F,sn);
      glVertex3f(cs,hi,sn);
      glVertex3f(cs,hf,sn); }
    glEnd(); }
  glPopMatrix();
}

void scene() {
  glPushMatrix();
  mySolidCylinder(n,m);
  glPopMatrix();
}

void affichageLumiere(void) {
  switch ( scn ) {
    case 2 :
      { glDisable(GL_LIGHTING);
        glutSolidSphere(0.05,36,36);
        glEnable(GL_LIGHTING); }
      break;
    case 3 :
      { const GLfloat pos[] = { 1.0,0.0,1.0,1.0 };
        glPushMatrix();
        glDisable(GL_LIGHTING);
        glTranslatef(pos[0],pos[1],pos[2]);
        glutSolidSphere(0.05,36,36);
        glEnable(GL_LIGHTING);
        glPopMatrix(); }
      break;
    case 4 :
      { const GLfloat pos[] = {  2.0,0.0,2.0,1.0 };
        const GLfloat dir[] = {  -1.0,0.0,-1.0 };
        glPushMatrix();
        glDisable(GL_LIGHTING);
        glTranslatef(pos[0],pos[1],pos[2]);
        glutSolidSphere(0.05,36,36);
        glBegin(GL_LINES);
        glVertex3f( 0.0F,0.0F, 0.0F);
        glVertex3f(-0.4F,0.0F,-0.4F);
        glEnd();
        glEnable(GL_LIGHTING);
        glPopMatrix(); }
      break;
    case 5 :
      { const GLfloat pos[] = {  p,0.0,p,1.0 };
        glPushMatrix();
        glDisable(GL_LIGHTING);
        glTranslatef(pos[0],pos[1],pos[2]);
        glutSolidSphere(0.05,36,36);
        glEnable(GL_LIGHTING);
        glPopMatrix(); }
      break;
    case 6 :
      { const GLfloat pos[] = {  2.0,0.0,2.0,1.0 };
        const GLfloat dir[] = {  -1.0,0.0,-1.0 };
        glPushMatrix();
        glDisable(GL_LIGHTING);
        glRotatef(r,0.0F,1.0F,0.0F);
        glTranslatef(pos[0],pos[1],pos[2]);
        glBegin(GL_LINES);
        glVertex3f( 0.0F,0.0F, 0.0F);
        glVertex3f(-0.4F,0.0F,-0.4F);
        glEnd();
        glutSolidSphere(0.05,36,36);
        glEnable(GL_LIGHTING);
        glPopMatrix(); }
      break; }
}

/* Fonction executee lors d'un rafraichissement */
/* de la fenetre de dessin                      */

void display(void) {
  glClearColor(0.75,0.75,0.75,1.0);
  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);
  switch ( scn ) {
    case 0 :
      { glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT,noir);
        glMaterialfv(GL_FRONT_AND_BACK,GL_EMISSION,noir);
        glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,bleuatre);
        glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,jaunatre);
        glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,64.0F);
        const GLfloat dir[] = {  1.0,0.0,1.0,0.0 };
        glLightfv(GL_LIGHT0,GL_POSITION,dir);
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,180.0F);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,0); }
      break;
    case 1 :
      { { glMaterialfv(GL_FRONT,GL_AMBIENT,noir);
          glMaterialfv(GL_FRONT,GL_EMISSION,noir);
          glMaterialfv(GL_FRONT,GL_DIFFUSE,bleuatre);
          glMaterialfv(GL_FRONT,GL_SPECULAR,jaunatre);
          glMaterialf(GL_FRONT,GL_SHININESS,64.0F); }
        { glMaterialfv(GL_BACK,GL_AMBIENT,noir);
          glMaterialfv(GL_BACK,GL_EMISSION,noir);
          glMaterialfv(GL_BACK,GL_DIFFUSE,grisClair);
          glMaterialfv(GL_BACK,GL_SPECULAR,grisFonce);
          glMaterialf(GL_BACK,GL_SHININESS,110.0F); }
        const GLfloat dir[] = {  1.0,0.0,1.0,0.0 };
        glLightfv(GL_LIGHT0,GL_POSITION,dir);
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,180.0F);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,1); }
      break;
    case 2 :
      { { glMaterialfv(GL_FRONT,GL_AMBIENT,noir);
          glMaterialfv(GL_FRONT,GL_EMISSION,noir);
          glMaterialfv(GL_FRONT,GL_DIFFUSE,bleuatre);
          glMaterialfv(GL_FRONT,GL_SPECULAR,jaunatre);
          glMaterialf(GL_FRONT,GL_SHININESS,64.0F); }
        { glMaterialfv(GL_BACK,GL_AMBIENT,noir);
          glMaterialfv(GL_BACK,GL_EMISSION,noir);
          glMaterialfv(GL_BACK,GL_DIFFUSE,grisClair);
          glMaterialfv(GL_BACK,GL_SPECULAR,grisFonce);
          glMaterialf(GL_BACK,GL_SHININESS,110.0F); }
        const GLfloat pos[] = {  0.0,0.0,0.0,1.0 };
        glLightfv(GL_LIGHT0,GL_POSITION,pos);
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,180.0F);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,1); }
      break;
    case 3 :
      { { glMaterialfv(GL_FRONT,GL_AMBIENT,noir);
          glMaterialfv(GL_FRONT,GL_EMISSION,noir);
          glMaterialfv(GL_FRONT,GL_DIFFUSE,bleuatre);
          glMaterialfv(GL_FRONT,GL_SPECULAR,jaunatre);
          glMaterialf(GL_FRONT,GL_SHININESS,64.0F); }
        { glMaterialfv(GL_BACK,GL_AMBIENT,noir);
          glMaterialfv(GL_BACK,GL_EMISSION,noir);
          glMaterialfv(GL_BACK,GL_DIFFUSE,grisClair);
          glMaterialfv(GL_BACK,GL_SPECULAR,grisFonce);
          glMaterialf(GL_BACK,GL_SHININESS,110.0F); }
        const GLfloat pos[] = {  1.0,0.0,1.0,1.0 };
        glLightfv(GL_LIGHT0,GL_POSITION,pos);
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,180.0F);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,1); }
      break;
    case 4 :
      { { glMaterialfv(GL_FRONT,GL_AMBIENT,noir);
          glMaterialfv(GL_FRONT,GL_EMISSION,noir);
          glMaterialfv(GL_FRONT,GL_DIFFUSE,bleuatre);
          glMaterialfv(GL_FRONT,GL_SPECULAR,jaunatre);
          glMaterialf(GL_FRONT,GL_SHININESS,64.0F); }
        { glMaterialfv(GL_BACK,GL_AMBIENT,noir);
          glMaterialfv(GL_BACK,GL_EMISSION,noir);
          glMaterialfv(GL_BACK,GL_DIFFUSE,grisClair);
          glMaterialfv(GL_BACK,GL_SPECULAR,grisFonce);
          glMaterialf(GL_BACK,GL_SHININESS,110.0F); }
        const GLfloat pos[] = {  2.0,0.0,2.0,1.0 };
        const GLfloat dir[] = {  -1.0,0.0,-1.0 };
        glLightfv(GL_LIGHT0,GL_POSITION,pos);
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,dir);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,ouv);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,1); }
      break;
    case 5 :
      { { glMaterialfv(GL_FRONT,GL_AMBIENT,noir);
          glMaterialfv(GL_FRONT,GL_EMISSION,noir);
          glMaterialfv(GL_FRONT,GL_DIFFUSE,bleuatre);
          glMaterialfv(GL_FRONT,GL_SPECULAR,jaunatre);
          glMaterialf(GL_FRONT,GL_SHININESS,64.0F); }
        { glMaterialfv(GL_BACK,GL_AMBIENT,noir);
          glMaterialfv(GL_BACK,GL_EMISSION,noir);
          glMaterialfv(GL_BACK,GL_DIFFUSE,grisClair);
          glMaterialfv(GL_BACK,GL_SPECULAR,grisFonce);
          glMaterialf(GL_BACK,GL_SHININESS,110.0F); }
        const GLfloat pos[] = {  p,0.0,p,1.0 };
        glLightfv(GL_LIGHT0,GL_POSITION,pos);
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,180.0F);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,1); }
      break;
    case 6 :
      { { glMaterialfv(GL_FRONT,GL_AMBIENT,noir);
          glMaterialfv(GL_FRONT,GL_EMISSION,noir);
          glMaterialfv(GL_FRONT,GL_DIFFUSE,bleuatre);
          glMaterialfv(GL_FRONT,GL_SPECULAR,jaunatre);
          glMaterialf(GL_FRONT,GL_SHININESS,64.0F); }
        { glMaterialfv(GL_BACK,GL_AMBIENT,noir);
          glMaterialfv(GL_BACK,GL_EMISSION,noir);
          glMaterialfv(GL_BACK,GL_DIFFUSE,grisClair);
          glMaterialfv(GL_BACK,GL_SPECULAR,grisFonce);
          glMaterialf(GL_BACK,GL_SHININESS,110.0F); }
        glPushMatrix();
        const GLfloat pos[] = {  2.0,0.0, 2.0,1.0 };
        const GLfloat dir[] = { -1.0,0.0,-1.0 };
        glRotatef(r,0.0F,1.0F,0.0F);
        glLightfv(GL_LIGHT0,GL_POSITION,pos);
        glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,dir);
        glPopMatrix();
        glLightfv(GL_LIGHT0,GL_DIFFUSE,jauneClair);
        glLightfv(GL_LIGHT0,GL_SPECULAR,jauneClair);
        glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,ouv);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHTING);
        glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,1); }
      break; }
  scene();
  affichageLumiere();
  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 idle1(void) {
  rx += 0.14256F;
  ry += 0.06117F;
  rz += 0.04174F;
  glutPostRedisplay();
}

void idle2(void) {
  static float d = -0.002F;
  p += d;
  if ( ( p > 2.0F ) || ( p < -2.0F ) )
    d *= -1.0F;
  idle1();
}

void idle3(void) {
  r += 0.1F ;
  idle1();
}

/* 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(10.0F,(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 'o' :
      ouv -= 0.1F;
      if ( ouv < 0.0F )
        ouv = 0.0F;
      glutPostRedisplay();
      break;
    case 'O' :
      ouv += 0.1F;
      if ( ouv > 90.0F )
        ouv = 90.0F;
      glutPostRedisplay();
      break;
    case 'n' :
      n--;
      if ( n < 3 )
        n = 3;
      glutPostRedisplay();
      break;
    case 'N' :
      n++;
      glutPostRedisplay();
      break;
    case 'm' :
      m--;
      if ( m < 1 )
        m = 1;
      glutPostRedisplay();
      break;
    case 'M' :
      m++;
      glutPostRedisplay();
      break;
    case 'c' :
      { static int culling = 0;
        culling = !culling;
        if ( culling )
          glEnable(GL_CULL_FACE);
          else
          glDisable(GL_CULL_FACE); }
      glutPostRedisplay();
      break;
    case 'f' :
      { static int face = 1;
        face = !face;
        glPolygonMode(GL_FRONT_AND_BACK,( face ) ? GL_FILL : GL_LINE); }
      glutPostRedisplay();
      break;
    case 0x0D :
      scn = (scn+1)%7;
      switch ( scn ) {
        case 0 :
        case 1 :
        case 2 :
        case 3 :
        case 4 :
          glutIdleFunc(idle1);
          break;
        case 5 :
          glutIdleFunc(idle2);
          break;
        case 6 :
          glutIdleFunc(idle3);
          break; }
      glutPostRedisplay();
      break;
    case 0x20 :
      { static int anim = 1;
        anim = !anim;
        switch ( scn ) {
          case 0 :
          case 1 :
          case 2 :
          case 3 :
          case 4 :
            glutIdleFunc(( anim ) ? idle1 : NULL);
            break;
          case 5 :
            glutIdleFunc(( anim ) ? idle2 : NULL);
            break;
          case 6 :
            glutIdleFunc(( anim ) ? idle3 : NULL);
            break; } }
      break;
    case 0x1B :
      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; }
}

/* Fonction principale                          */

int main(int argc,char **argv) {
  glutInit(&argc,argv);
  glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
  glutInitWindowSize(300,300); 
  glutInitWindowPosition(50,50); 
  glutCreateWindow("Cylindre par facettes avec matériel et lumière"); 
  init();
  glutKeyboardFunc(keyboard);
  glutSpecialFunc(special);
  glutReshapeFunc(reshape);
  glutIdleFunc(idle1);
  glutDisplayFunc(display);
  glutMainLoop();
  return(0);
}