/* Auteur: Nicolas JANEY                 */
/* nicolas.janey@univ-fcomte.fr          */
/* Decembre 2001                         */
/* Schema pour un calcul d'illumination  */
/* de Gouraud                            */

#include <stdlib.h>

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

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

typedef float couleur[4];

struct facette3 {
  vecteur pa;
  couleur ca;
  vecteur pb;
  couleur cb;
  vecteur pc;
  couleur cc; } ;

static float px1;
static float pz1;
static float px2;
static float pz2;
static float px;
static float pz;
static float h1;
static float h2;
static int cr1;
static int cv1;
static int cb1;
static int cr2;
static int cv2;
static int cb2;
static int cr;
static int cv;
static int cb;
static int f1;
static int f2;
static float posx = 0.5F;
static float posy = 0.0F;
static facette3 f = { { 0.05F,0.8F,0.4F },
                      { 0.9F,0.05F,0.8F },
                      { -0.55F,-0.2F,-0.5F },
                      { 0.1F,0.9F,0.7F },
                      { 0.85F,-0.75F,-0.1F } ,
                      { 0.7F,0.6F,0.1F } };

void myinit(void) {
  GLfloat l_pos[] = { -1.0,1.0,1.0,0.0 };
  glLightfv(GL_LIGHT0,GL_POSITION,l_pos);
  glEnable(GL_LIGHT0);
  glEnable(GL_AUTO_NORMAL);
  glEnable(GL_NORMALIZE);
  glClearColor(0.7F,0.7F,0.8F,1.0F) ;
  glDepthFunc(GL_LESS);
}

int intersection(vecteur pi,vecteur pf,couleur ci,couleur cf,float y,float *x,float *z,int *r,int *v,int *b,float *h) {
  if ( ( y > pi[1] ) || ( y < pf[1] ) )
    return(0);
  float fact = (y-pf[1])/(pi[1]-pf[1]);
  *h = 1.0F-fact;
  *x = pf[0] + fact*(pi[0]-pf[0]);
  *z = pf[2] + fact*(pi[2]-pf[2]);
  *r =(int) ((cf[0] + fact*(ci[0]-cf[0]))*255);
  *v =(int) ((cf[1] + fact*(ci[1]-cf[1]))*255);
  *b =(int) ((cf[2] + fact*(ci[2]-cf[2]))*255);
  return(1);
}

void evaluationIntersections(void) {
  if ( intersection(f.pa,f.pb,f.ca,f.cb,posy,&px1,&pz1,&cr1,&cv1,&cb1,&h1) ) {
    if ( !intersection(f.pa,f.pc,f.ca,f.cc,posy,&px2,&pz2,&cr2,&cv2,&cb2,&h2) )
      intersection(f.pb,f.pc,f.cb,f.cc,posy,&px2,&pz2,&cr2,&cv2,&cb2,&h2); }
    else {
    intersection(f.pa,f.pc,f.ca,f.cc,posy,&px2,&pz2,&cr2,&cv2,&cb2,&h2);
    intersection(f.pb,f.pc,f.cb,f.cc,posy,&px1,&pz1,&cr1,&cv1,&cb1,&h1); }
  px = px1 + posx*(px2-px1);
  pz = pz1 + posx*(pz2-pz1);
  cr =(int) (cr1 + posx*(cr2-cr1));
  cv =(int) (cv1 + posx*(cv2-cv1));
  cb =(int) (cb1 + posx*(cb2-cb1));
}

void display(void) {
  glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  glPushMatrix();
  manipulateurSouris();
  manipulateurClavier();
  glColor4fv(couleurGrisClair());
  glEnable(GL_DEPTH_TEST);
  glBegin(GL_POLYGON);
  glColor4fv(f.ca);
  glVertex3fv(f.pa);
  glColor4fv(f.cb);
  glVertex3fv(f.pb);
  glColor4fv(f.cc);
  glVertex3fv(f.pc);
  glEnd();
  glDisable(GL_DEPTH_TEST);
  glColor4fv(couleurNoir());
  glBegin(GL_LINES);
  glVertex3f(px1,posy,pz1);
  glVertex3f(px2,posy,pz2);
  glEnd();
  glBegin(GL_LINE_LOOP);
  glVertex3fv(f.pa);
  glVertex3fv(f.pb);
  glVertex3fv(f.pc);
  glEnd();
  glEnable(GL_DEPTH_TEST);
  glEnable(GL_LIGHTING);
  if ( posy > f.pb[1] ) { 
    glPushMatrix();
    glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurVert());
    glTranslatef(f.pa[0],f.pa[1],f.pa[2]);
    flecheEnVolume(px1-f.pa[0],posy-f.pa[1],pz1-f.pa[2],0.03F,0.1F,0.012F);
    glPopMatrix(); }
    else {
    glPushMatrix();
    glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurRouge());
    glTranslatef(f.pb[0],f.pb[1],f.pb[2]);
    flecheEnVolume(px1-f.pb[0],posy-f.pb[1],pz1-f.pb[2],0.03F,0.1F,0.012F);
    glPopMatrix(); }
  glPushMatrix();
  glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurBleu());
  glTranslatef(f.pa[0],f.pa[1],f.pa[2]);
  flecheEnVolume(px2-f.pa[0],posy-f.pa[1],pz2-f.pa[2],0.03F,0.1F,0.012F);
  glPopMatrix();
  glPushMatrix();
  glMaterialfv(GL_FRONT,GL_DIFFUSE,couleurJaune());
  glTranslatef(px1,posy,pz1);
  flecheEnVolume(px-px1,0.0F,pz-pz1,0.03F,0.1F,0.012F);
  glPopMatrix();
  glDisable(GL_LIGHTING);
  glColor4fv(couleurGrisFonce());
  glEnable(GL_LIGHTING);
  float coul1[4] = { cr1/255.0F,cv1/255.0F,cb1/255.0F };
  glMaterialfv(GL_FRONT,GL_DIFFUSE,coul1);
  glPushMatrix();
  glTranslatef(px1,posy,pz1);
  glutSolidSphere(0.035F,10,10);
  glPopMatrix();
  float coul2[4] = { cr2/255.0F,cv2/255.0F,cb2/255.0F };
  glMaterialfv(GL_FRONT,GL_DIFFUSE,coul2);
  glPushMatrix();
  glTranslatef(px2,posy,pz2);
  glutSolidSphere(0.035F,10,10);
  glPopMatrix();
  float coul[4] = { cr/255.0F,cv/255.0F,cb/255.0F };
  glMaterialfv(GL_FRONT,GL_DIFFUSE,coul);
  glPushMatrix();
  glTranslatef(px,posy,pz);
  glutSolidSphere(0.035F,10,10);
  glPopMatrix();
  glDisable(GL_LIGHTING);
  glDisable(GL_DEPTH_TEST);
  glColor4fv(couleurBleu());
  setAlignement(RIGHT);
  if ( posy > f.pb[1] ) { 
    placeFontCursor((f.pa[0]+px1)/2.0F-0.05F,(f.pa[1]+posy)/2.0F,(f.pa[2]+pz1)/2.0F) ;
    simpleBitmapOutput(REGULAR8x13,"PaP1 = h1PaPb") ;
    deplacementCursor(-2,-5,0) ;
    simpleBitmapOutput(DESSIN,"TTTTF      TTTTF") ; }
    else {
    placeFontCursor((f.pb[0]+px1)/2.0F-0.05F,(f.pb[1]+posy)/2.0F,(f.pb[2]+pz1)/2.0F) ;
    simpleBitmapOutput(REGULAR8x13,"PbP1 = h1PbPc") ;
    deplacementCursor(-2,-5,0) ;
    simpleBitmapOutput(DESSIN,"TTTTF      TTTTF") ; }
  setAlignement(LEFT);
  placeFontCursor((f.pa[0]+px2)/2.0F+0.05F,(f.pa[1]+posy)/2.0F,(f.pa[2]+pz2)/2.0F) ;
  simpleBitmapOutput(REGULAR8x13,"PaP2 = h2PaPb") ;
  deplacementCursor(0,-5,0) ;
  simpleBitmapOutput(DESSIN,"TTTTF      TTTTF") ;
  setAlignement(CENTER);
  placeFontCursor(px,posy-0.1F,pz) ;
  simpleBitmapOutput(REGULAR8x13,"P1P = hP1P2") ;
  deplacementCursor(0,-5,0) ;
  simpleBitmapOutput(DESSIN,"TTTF     TTTTF") ;
  setAlignement(CENTER);
  placeFontCursor(f.pa[0]+0.05F,f.pa[1]+0.05F,f.pa[2]+0.05F) ;
  simpleBitmapOutput(REGULAR8x13,"Pa (Ca)") ;
  setAlignement(RIGHT);
  placeFontCursor(f.pb[0]-0.05F,f.pb[1],f.pb[2]+0.05F) ;
  simpleBitmapOutput(REGULAR8x13,"Pb (Cb)") ;
  setAlignement(LEFT);
  placeFontCursor(f.pc[0]+0.05F,f.pc[1],f.pc[2]+0.05F) ;
  simpleBitmapOutput(REGULAR8x13,"Pc (Cc)") ;
  setAlignement(CENTER);
  placeFontCursor(px1-0.1F,posy+0.1F,pz1+0.1F) ;
  simpleBitmapOutput(REGULAR8x13,"P1") ;
  placeFontCursor(px2+0.1F,posy+0.1F,pz2+0.1F) ;
  simpleBitmapOutput(REGULAR8x13,"P2") ;
  placeFontCursor(px+0.1F,posy+0.1F,pz+0.1F) ;
  simpleBitmapOutput(REGULAR8x13,"P") ;
  setAlignement(LEFT);
  glPopMatrix();
  glPushMatrix();
  if ( posy > f.pb[1] ) { 
    placeFontCursor(-1.4F,-0.82F,0.1F) ;
    simpleBitmapOutput(REGULAR8x13,"C1 = Ca+h1(Cb-Ca)") ; }
    else {
    placeFontCursor(-1.4F,-0.82F,0.1F) ;
    simpleBitmapOutput(REGULAR8x13,"C1 = Cb+h1(Cc-Cb)") ; }
  placeFontCursor(-1.4F,-0.95F,0.1F) ;
  simpleBitmapOutput(REGULAR8x13,"C2 = Ca+h2(Cc-Ca)") ;
  placeFontCursor(0.4F,-0.95F,0.1F) ;
  simpleBitmapOutput(REGULAR8x13,"C = C1+h(C2-C1)") ;
  glPopMatrix();
  glFlush();
  glutSwapBuffers();
  glutPostWindowRedisplay(f2) ;
}

void special(int k,int x,int y) {
  if ( specialManipulateur(k,x,y) ) {
    glutPostWindowRedisplay(f1); }
}

void key2(unsigned char key,int x,int y) {
  switch ( key ) {
    case '4'  : posx -= 0.01F;
                if ( posx < 0.0F )
                  posx = 0.0F;
                evaluationIntersections();
                glutPostWindowRedisplay(f1) ;
                break ;
    case '6'  : posx += 0.01F;
                if ( posx > 1.0F )
                  posx = 1.0F;
                evaluationIntersections();
                glutPostWindowRedisplay(f1) ;
                break ;
    case 43   : posy += 0.01F;
                if ( posy > f.pa[1] )
                  posy = f.pa[1];
                evaluationIntersections();
                glutPostWindowRedisplay(f1) ;
                break ;
    case 45   : posy -= 0.01F;
                if ( posy < f.pc[1] )
                  posy = f.pc[1];
                evaluationIntersections();
                glutPostWindowRedisplay(f1) ;
                break ;
    case 0x1B : exit(0);
                break ; }
}

void key(unsigned char key,int x,int y) {
  if ( keyManipulateur(key,x,y) )
    glutPostWindowRedisplay(f1);
    else
    key2(key,x,y);
}

void reshape2(int w,int h) {
  glViewport(0,0,w,h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  glOrtho(0,w,-h,0,-1.0,1.0); 
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
}

void display2() {
  glClear(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT);
  glClearColor(0.0F,0.0F,0.0F,1.0F) ;
  glPushAttrib(GL_LIGHTING);
  glDisable(GL_LIGHTING);
  glPushMatrix();
  glColor4fv(couleurBlanc());
  float pos = 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"PA : %6.3f %6.3f %6.3f",f.pa[0],f.pa[1],f.pa[2]) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"PB : %6.3f %6.3f %6.3f",f.pb[0],f.pb[1],f.pb[2]) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"PC : %6.3f %6.3f %6.3f",f.pc[0],f.pc[1],f.pc[2]) ;
  pos += 1.0F;
  glColor4fv(f.ca);
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"CA : %6d %6d %6d",(int) (f.ca[0]*255),(int) (f.ca[1]*255),(int) (f.ca[2]*255)) ;
  pos += 1.0F;
  glColor4fv(f.cb);
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"CB : %6d %6d %6d",(int) (f.cb[0]*255),(int) (f.cb[1]*255),(int) (f.cb[2]*255)) ;
  pos += 1.0F;
  glColor4fv(f.cc);
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"CC : %6d %6d %6d",(int) (f.cc[0]*255),(int) (f.cc[1]*255),(int) (f.cc[2]*255)) ;
  glColor4fv(couleurBlanc());
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"h1 : %6.3f",h1) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"P1 : %6.3f %6.3f %6.3f",px1,posy,pz1) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"h2 : %6.3f",h2) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"P2 : %6.3f %6.3f %6.3f",px2,posy,pz2) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"h  : %6.3f",posx) ;
  pos += 1.0F;
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"P  : %6.3f %6.3f %6.3f",px,posy,pz) ;
  pos += 1.0F;
  glColor3f(cr1/255.0F,cv1/255.0F,cb1/255.0F);
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"C1 : %6d %6d %6d",cr1,cv1,cb1) ;
  pos += 1.0F;
  glColor3f(cr2/255.0F,cv2/255.0F,cb2/255.0F);
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"C2 : %6d %6d %6d",cr2,cv2,cb2) ;
  pos += 1.0F;
  glColor3f(cr/255.0F,cv/255.0F,cb/255.0F);
  placeFontCursor(5.0F,-pos*20.0F,0.0F) ;
  simpleBitmapOutput(REGULAR8x13,"C  : %6d %6d %6d",cr,cv,cb) ;
  glPopMatrix();
  glPopAttrib();
  glutSwapBuffers();
}

int main(int argc,char **argv) {
  glutInit(&argc,argv);
  evaluationIntersections();
  glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
  glutInitWindowSize(450,300); 
  glutInitWindowPosition(10,50); 
  f1 = glutCreateWindow("Schema Gouraud");
  myinit(); 
  creationMenuBasique();
  setParametresOrthoBasique(-1.0,1.0,-1.0,1.0,-5.0,5.0);
  setManipulateurDistance(1.0F);
  glutReshapeFunc(reshapeOrthoBasique);
  glutKeyboardFunc(key);
  glutSpecialFunc(special);
  glutMotionFunc(motionBasique);
  glutMouseFunc(sourisBasique);
  glutDisplayFunc(display);
  glutInitWindowSize(260,310);
  glutInitWindowPosition(480,45);
  glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
  f2 = glutCreateWindow("Valeurs");
  creationMenuBasique();
  glutDisplayFunc(display2);
  glutReshapeFunc(reshape2);
  glutKeyboardFunc(key2);
  glutSpecialFunc(special);
  glutMainLoop();
  return(0);
}