/* Auteur: Nicolas JANEY                */
/* nicolas.janey@univ-fcomte.fr         */
/* Avril 2001                           */
/* Fonctions de dessin de cylindre      */

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

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

#include "ModuleCouleurs.h"
#include "ModuleManipulateur.h"
#include "ModuleMenus.h"
#include "ModuleReshape.h"

static int np = 40;

struct point3D {
  float x ;
  float y ;
  float z ; } ;

struct vecteur3D {
  float dx ;
  float dy ;
  float dz ; } ;

void cylindre(double r,double h,int np) {
  int i;
  point3D *tab =(point3D *) malloc(2*np*sizeof(point3D)) ;
  for ( i = 0 ; i < np ; i++ ) {
    double a = 3.14159/np*2*i ;
    double cs = cos(a) ;
    double sn = sin(a) ;
    tab[i].x = tab[i+np].x =(float) (r*cs) ;
    tab[i].y =(float) (h/2.0) ;
    tab[i+np].y =(float) (-h/2.0) ;
    tab[i].z = tab[i+np].z =(float) (-r*sn) ; }
  glBegin(GL_POLYGON) ;
  for ( i = 0 ; i < np ; i++ ) {
    glVertex3fv((float *) &tab[i]) ; }
  glEnd() ;
  glBegin(GL_POLYGON) ;
  for ( i = 2*np-1 ; i >= np ; i-- ) {
    glVertex3fv((float *) &tab[i]) ; }
  glEnd() ;
  glBegin(GL_QUAD_STRIP) ;
  for ( i = 0 ; i <= np ; i++ ) {
    glVertex3fv((float *) &tab[i%np]);
    glVertex3fv((float *) &tab[(i%np)+np]); }
  glEnd() ;
  free(tab) ;
}

void cylindreAvecNormales(double r,double h,int np) {
  float normale[3];
  int i;
  glGetFloatv(GL_CURRENT_NORMAL,normale) ;
  point3D *tab =(point3D *) malloc(2*np*sizeof(point3D)) ;
  vecteur3D *norm =(vecteur3D *) malloc(np*sizeof(vecteur3D)) ;
  for ( i = 0 ; i < np ; i++ ) {
    double a = 3.14159/np*2*i ;
    double cs = cos(a) ;
    double sn = sin(a) ;
    tab[i].x = tab[i+np].x =(float) (r*cs) ;
    tab[i].y =(float) (h/2.0) ;
    tab[i+np].y =(float) (-h/2.0) ;
    tab[i].z = tab[i+np].z =(float) (-r*sn) ;
    norm[i].dx =(float) cs ;
    norm[i].dy =(float) 0.0 ;
    norm[i].dz =(float) -sn ; }
  glBegin(GL_POLYGON) ;
  for ( i = 0 ; i < np ; i++ ) {
    glNormal3f(0.0f,1.0f,0.0f);
    glVertex3fv((float *) &tab[i]) ; }
  glEnd() ;
  glBegin(GL_POLYGON) ;
  for ( i = 2*np-1 ; i >= np ; i-- ) {
    glNormal3f(0.0f,-1.0f,0.0f);
    glVertex3fv((float *) &tab[i]) ; }
  glEnd() ;
  glBegin(GL_QUAD_STRIP) ;
  for ( i = 0 ; i <= np ; i++ ) {
    glNormal3fv((float *) &norm[i%np]);
    glVertex3fv((float *) &tab[i%np]);
    glVertex3fv((float *) &tab[(i%np)+np]); }
  glEnd() ;
  free(tab) ;
  free(norm) ;
  glNormal3fv(normale) ;
}

void display(void) {
  glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  glPushMatrix();
  manipulateurSouris();
  manipulateurClavier();
  glPushMatrix();
  glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,couleurBleu()) ;
  glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,couleurJaune()) ;
  glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,90) ;
  glTranslatef(0.0F,0.65F,0.0F) ;
  glNormal3f(0.0f,0.0f,1.0f);
  cylindre(0.4,0.8,np) ;
  glPopMatrix();
  glPushMatrix();
  glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,couleurRouge()) ;
  glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,couleurJaune()) ;
  glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,90) ;
  glTranslatef(0.0F,-0.65F,0.0F) ;
  cylindreAvecNormales(0.4,0.8,np) ;
  glPopMatrix();
  glPopMatrix();
  glFlush();
  glutSwapBuffers();
}

void myinit (void) {
  glClearColor(0.5F,0.5F,0.5F,0.0F);
  glShadeModel(GL_SMOOTH);
  glEnable(GL_AUTO_NORMAL);
  glEnable(GL_NORMALIZE);
  glEnable(GL_DEPTH_TEST);
  glEnable(GL_LIGHTING);
  glEnable(GL_LIGHT0);
  glLightfv(GL_LIGHT0,GL_SPECULAR,couleurJauneClair()) ;
  glEnable(GL_CULL_FACE);
  glCullFace(GL_BACK);
}

void key(unsigned char key,int x,int y) {
  if ( keyManipulateur(key,x,y) )
    glutPostRedisplay();
    else
    switch ( key ) {
      case 43     : np++ ;
                    glutPostRedisplay();
                    break ;
      case 45     : np-- ;
                    if ( np < 3 )
                      np = 3 ;
                    glutPostRedisplay();
                    break ; }
}

int main(int argc,char **argv) {
  glutInit(&argc,argv);
  glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
  glutInitWindowSize(300,300); 
  glutInitWindowPosition(50,50); 
  glutCreateWindow("Cylindre"); 
  myinit(); 
  creationMenuBasique();
  setParametresOrthoBasique(-1.3F,1.3F,-1.3F,1.3F,-500.0,500.0);
  setManipulateurDistance(1.0F);
  glutReshapeFunc(reshapeOrthoBasique);
  glutKeyboardFunc(key);
  glutSpecialFunc(specialBasique);
  glutMotionFunc(motionBasique);
  glutMouseFunc(sourisBasique);
  glutDisplayFunc(display);
  glutMainLoop();
  return(0);
}