/* Auteur: Nicolas JANEY                  */
/* nicolas.janey@univ-fcomte.fr           */
/* Juin 2001                              */
/* Shema de realisation d'une projection  */
/* en perspective                         */

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

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

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

static int aff = 0;
static float pax = 6.0F;
static float pay = -4.0F;
static float paz = -14.0F;
static float pbx = -4.0F;
static float pby = 3.0F;
static float pbz = -9.0F;
static float poz = 15.0F;

void myinit(void) {
  glDepthFunc(GL_LESS);
  glEnable(GL_DEPTH_TEST);
  glEnable(GL_NORMALIZE) ;
  glEnable(GL_LIGHT0);
  glClearColor(0.5F,0.5F,0.5F,0.0F);
}

void axeDeProjection(float x1,float y1,float z1,float x2,float y2,float z2,float fact) {
  float dx = x2-x1;
  float dy = y2-y1;
  float dz = z2-z1;
  glBegin(GL_LINES);
  glVertex3f(x1-fact*dx,y1-fact*dy,z1-fact*dz);
  glVertex3f(x1+fact*dx,y1+fact*dy,z1+fact*dz);
  glEnd();
}

void display(void) {
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glPushMatrix();
  manipulateurSouris();
  manipulateurClavier();
  glColor4fv(couleurBlanc());
  glBegin(GL_LINE_LOOP);
  glVertex3f(8.0F,6.0F,-3.0F);
  glVertex3f(8.0F,-6.0F,-3.0F);
  glVertex3f(-8.0F,-6.0F,-3.0F);
  glVertex3f(-8.0F,6.0F,-3.0F);
  glEnd();
  glColor4fv(couleurJaune());
  glBegin(GL_LINES);
  glVertex3f(pax,pay,paz);
  glVertex3f(pbx,pby,pbz);
  glEnd();
  float fact1 = (poz+3.0F)/(poz-paz);
  float xaprim = pax*fact1;
  float yaprim = pay*fact1;
  float fact2 = (poz+3.0F)/(poz-pbz);
  float xbprim = pbx*fact2;
  float ybprim = pby*fact2;
  glColor4fv(couleurRouge());
  glBegin(GL_LINES);
  glVertex3f(xaprim,yaprim,-3.0F);
  glVertex3f(xbprim,ybprim,-3.0F);
  glEnd();
  glColor4fv(couleurBlanc());
  placeFontCursor(0.0F,-1.0F,poz+4.0F);
  simpleBitmapOutput("%s","Centre de projection");
  placeFontCursor(0.0F,-9.0F,0.0);
  simpleBitmapOutput("%s","Plan de projection");
  glEnable(GL_LIGHTING);
  glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurRougeFonce());
  glPushMatrix();
  glTranslatef(0.0F,0.0F,-15.0F);
  flecheEnVolume(0.0F,0.0F,25.0F,0.3F,1.5F,0.1F) ;
  glPopMatrix();
  glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurVertFonce());
  glPushMatrix();
  glTranslatef(pax,pay,paz);
  flecheEnVolume(xaprim-pax,yaprim-pay,-3.0F-paz,0.3F,1.5F,0.1F) ;
  glPopMatrix();
  glPushMatrix();
  glTranslatef(pbx,pby,pbz);
  flecheEnVolume(xbprim-pbx,ybprim-pby,-3.0F-pbz,0.3F,1.5F,0.1F) ;
  glPopMatrix();
  glDisable(GL_LIGHTING);
  glColor4fv(couleurJaune());
  placeFontCursor(pax+0.1F,pay+0.1F,paz+0.1F);
  simpleBitmapOutput("%s","A");
  placeFontCursor(pbx+0.1F,pby+0.1F,pbz+0.1F);
  simpleBitmapOutput("%s","B");
  glColor4fv(couleurRouge());
  placeFontCursor(xaprim+0.1F,yaprim+0.1F,-2.9F);
  simpleBitmapOutput("%s","A'");
  placeFontCursor(xbprim+0.1F,ybprim+0.1F,-2.9F);
  simpleBitmapOutput("%s","B'");
  axeDeProjection(0.0F,0.0F,1.0F,0.0F,0.0F,-1.0F,50);
  glColor4fv(couleurVert());
  axeDeProjection(pax,pay,paz,xaprim,yaprim,-3.0F,50);
  axeDeProjection(pbx,pby,pbz,xbprim,ybprim,-3.0F,50);
  glPopMatrix();
  glFlush();
  glutSwapBuffers();
}
/* -------------------------------------------------- */
void key(unsigned char key,int x,int y) {
  if ( keyManipulateur(key,x,y) )
    glutPostRedisplay();
    else
    switch ( key ) {
      case 'e'  : pax += 0.2F;
                  if ( pax > 8.0F )
                    pax = 8.0F;
                  glutPostRedisplay();
                  break;
      case 'E'  : pax -= 0.2F;
                  if ( pax < -8.0F )
                    pax = -8.0F;
                  glutPostRedisplay();
                  break;
      case 'd'  : pbx += 0.2F;
                  if ( pbx > 8.0F )
                    pbx = 8.0F;
                  glutPostRedisplay();
                  break;
      case 'D'  : pbx -= 0.2F;
                  if ( pbx < -8.0F )
                    pbx = -8.0F;
                  glutPostRedisplay();
                  break;
      case 'r'  : pay += 0.2F;
                  if ( pay > 8.0F )
                    pay = 8.0F;
                  glutPostRedisplay();
                  break;
      case 'R'  : pay -= 0.2F;
                  if ( pay < -8.0F )
                    pay = -8.0F;
                  glutPostRedisplay();
                  break;
      case 'f'  : pby += 0.2F;
                  if ( pby > 8.0F )
                    pby = 8.0F;
                  glutPostRedisplay();
                  break;
      case 'F'  : pby -= 0.2F;
                  if ( pby < -8.0F )
                    pby = -8.0F;
                  glutPostRedisplay();
                  break;
      case 't'  : paz += 0.2F;
                  glutPostRedisplay();
                  break;
      case 'T'  : paz -= 0.2F;
                  glutPostRedisplay();
                  break;
      case 'g'  : pbz += 0.2F;
                  glutPostRedisplay();
                  break;
      case 'G'  : pbz -= 0.2F;
                  glutPostRedisplay();
                  break;
      case 32   : aff = (aff+1)%2 ; 
                  glutPostRedisplay();
                  break; }
}
/* -------------------------------------------------- */
int main(int argc,char **argv) {
  glutInit(&argc,argv);
  glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGBA|GLUT_DEPTH);
  glutInitWindowPosition(10,10);
  glutInitWindowSize(400,250);
  glutCreateWindow("Schema: Projection en perspective");
  myinit();
  creationMenuBasique();
  setParametresOrthoBasique(-10.0,10.0,-10.0,10.0,-500.0,500.0);
  setManipulateurDistance(1.0F);
  setManipulateurClavierAngle(22.0F,-40.0F,0.0F) ;
  glutReshapeFunc(reshapeOrthoBasique);
  glutKeyboardFunc(key);
  glutSpecialFunc(specialBasique);
  glutMotionFunc(motionBasique);
  glutMouseFunc(sourisBasique);
  glutDisplayFunc(display);
  glutMainLoop();
  return(0);
}

/* ************************************************** */