/* Auteur: Nicolas JANEY         */
/* nicolas.janey@univ-fcomte.fr  */
/* Novembre 2001                 */
/* Exemple de bump mapping       */

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

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

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

int aff = 0;
int anim = 0;
int disci = 100;
int discj = 10;
float ang = 0.8F;
float da = -0.04F;
float fact = 15.0F;
float amp = 10.F;

void normalize(float *x,float*z) {
  float d =(float) sqrt(*x * *x + *z * *z);
  *x /= d;
  *z /= d;
}

void myinit(void) {
  glClearColor(0.5F,0.5F,1.0F,1.0F) ;
  glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurGrisClair());
  glEnable(GL_LIGHTING);
  glEnable(GL_LIGHT0);
  glDepthFunc(GL_LESS);
  glEnable(GL_DEPTH_TEST);
}

void generationSommetBump(float x,float y) {
  float nxi = fact*sin(x*fact);
  float nzi = amp;
  normalize(&nxi,&nzi);
  glNormal3f(nxi,0.0F,nzi);
  glVertex2f(x,y);
}
                   
void idle(void) {
  ang += da ;
  if ( ( ang < -0.8F ) || ( ang > 0.8F ) )
    da = -da ;
  glutPostRedisplay() ;
}

void facetteBumpee(void) {
  switch ( aff ) {
    case 0 : glNormal3f(0.0F,0.0F,1.0F);
             glBegin(GL_QUADS);
             glVertex2f(-1.0F,-0.5F);
             glVertex2f(1.0F,-0.5F);
             glVertex2f(1.0F,0.5F);
             glVertex2f(-1.0F,0.5F);
             glEnd();
             break;
    case 1 : { glNormal3f(0.0F,0.0F,1.0F);
               glBegin(GL_QUADS);
               for ( int i = 0 ; i < disci ; i++ )
                 for ( int j = 0 ; j < discj ; j++ ) {
                   glVertex2f(-1.0F+i*2.0F/disci,-0.5F+(float)j/discj);
                   glVertex2f(-1.0F+(i+1)*2.0F/disci,-0.5F+(float)j/discj);
                   glVertex2f(-1.0F+(i+1)*2.0F/disci,-0.5F+(float)(j+1)/discj);
                   glVertex2f(-1.0F+i*2.0F/disci,-0.5F+(float)(j+1)/discj); }
               glEnd();
               break; }
    case 2 : { glBegin(GL_QUADS);
               for ( int i = 0 ; i < disci ; i++ )
                 for ( int j = 0 ; j < discj ; j++ ) {
                   generationSommetBump(-1.0F+i*2.0F/disci,-0.5F+(float)j/discj);
                   generationSommetBump(-1.0F+(i+1)*2.0F/disci,-0.5F+(float)j/discj);
                   generationSommetBump(-1.0F+(i+1)*2.0F/disci,-0.5F+(float)(j+1)/discj);
                   generationSommetBump(-1.0F+i*2.0F/disci,-0.5F+(float)(j+1)/discj); }
               glEnd();
               break; } }
}

void toleOndulee(void) {
  glBegin(GL_QUADS);
  for ( int i = 0 ; i < disci ; i++ )
    for ( int j = 0 ; j < discj ; j++ ) {
      float xi = -1.0F+i*2.0F/disci;
      float xj = -1.0F+(i+1)*2.0F/disci;
      float zi = cos(xi*fact)/amp;
      float zj = cos(xj*fact)/amp;
      float nxi = fact*sin(xi*fact);
      float nxj = fact*sin(xj*fact);
      float nzi = amp;
      float nzj = amp;
      normalize(&nxi,&nzi);
      normalize(&nxj,&nzj);
      glNormal3f(nxi,0.0F,nzi);
      glVertex3f(xi,-0.5F+(float)(j+1)/discj,zi);
      glVertex3f(xi,-0.5F+(float)j/discj,zi);
      glNormal3f(nxj,0.0F,nzj);
      glVertex3f(xj,-0.5F+(float)j/discj,zj);
      glVertex3f(xj,-0.5F+(float)(j+1)/discj,zj); }
  glEnd();
}

void display(void) {
  glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  glPushMatrix();
  manipulateurSouris();
  manipulateurClavier();
  GLfloat l_dir[] = { sin(ang),0.0,cos(ang),0.0 };
  glLightfv(GL_LIGHT0,GL_POSITION,l_dir);
  if ( aff == 2 ) {
    glTranslatef(0.0F,-0.6F,0.0F);
    toleOndulee();
    glTranslatef(0.0F,1.2F,0.0F); }
  facetteBumpee();
  glPopMatrix();
  glFlush();
  glutSwapBuffers();
}

void key(unsigned char key,int x,int y) {
  if ( keyManipulateur(key,x,y) )
    glutPostRedisplay();
    else
    switch ( key ) {
      case 'a'  : amp *= 1.1F;
                  glutPostRedisplay();
                  break;
      case 'A'  : amp /= 1.1F;
                  glutPostRedisplay();
                  break;
      case 'f'  : fact--;
                  if ( fact < 1.0F )
                    fact = 1.0F;
                  glutPostRedisplay();
                  break;
      case 'F'  : fact++;
                  glutPostRedisplay();
                  break;
      case ' '  : anim = (anim+1)%2;
                  if ( anim )
                    glutIdleFunc(idle);
                    else
                    glutIdleFunc(NULL);
                  glutPostRedisplay();
                  break;
      case 43   : disci++;
                  glutPostRedisplay();
                  break;
      case 45   : disci--;
                  if ( disci < 2 )
                    disci = 2;
                  glutPostRedisplay();
                  break;
      case 0x0D : aff = (aff+1)%3;
                  glutPostRedisplay();
                  break; }
}

int main(int argc,char **argv) {
  glutInit(&argc,argv);
  glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
  glutInitWindowSize(250,250); 
  glutInitWindowPosition(50,50); 
  glutCreateWindow("Bump mapping"); 
  myinit(); 
  creationMenuBasique();
  setParametresOrthoBasique(-1.5,1.5,-1.5,1.5,-500.0,500.0);
  setManipulateurDistance(1.0F);
  glutReshapeFunc(reshapeOrthoBasique);
  glutKeyboardFunc(key);
  glutSpecialFunc(specialBasique);
  glutMotionFunc(motionBasique);
  glutMouseFunc(sourisBasique);
  glutDisplayFunc(display);
  glutMainLoop();
  return(0);
}