/* Energie r,v,b en double precision reelle     */
/*                                              */
/* Auteur: Nicolas JANEY                        */
/* nicolas.janey@univ-fcomte.fr                 */
/* Octobre 2010                                 */

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

#include "Energie.h"
#include "Direction3D.h"
#include "Position3D.h"
#include "FacetteTriangulaire.h"
#include "Couleur.h"
#include "LumierePonctuelle.h"

Energie::Energie(void):Couleur() {
}

Energie::Energie(double r,double v,double b):Couleur(r,v,b) {
}

Energie::Energie(Energie *e):Couleur(e->r,e->v,e->b) {
}

Energie::~Energie(void) {
}

void Energie::calculDiffusion(Position3D *p,FacetteTriangulaire *fct,Couleur *kd,LumierePonctuelle *lp) {
  Direction3D *n = fct->normale();
  Direction3D *l = new Direction3D(p,lp->p);
  double d = l->normalise();
  double ps = l->produitScalaire(n);
  if ( ps < 0.0 ) {
    r = v = b = 0.0; }
    else {
    double i = lp->e/(d*d)*ps;
    r = i*kd->r*lp->c->r;
    v = i*kd->v*lp->c->v;
    b = i*kd->b*lp->c->b; }
  delete(l);
  delete(n);
}

void Energie::calculReflexionSpeculaire(Position3D *p,FacetteTriangulaire *fct,Couleur *kr,LumierePonctuelle *lp,Position3D *obs) {
  Direction3D *n = fct->normale();
  Direction3D *l = new Direction3D(p,lp->p);
  double d = l->normalise();
  Direction3D *r = l->reflexion(n);
  if ( !r ) {
    this->r = this->v = this->b = 0.0;
    delete(l);
    delete(n);
    return; }
  Direction3D *po = new Direction3D(p,obs);
  po->normalise();
  double ps = r->produitScalaire(po);
  if ( ps < 0.0 ) {
    this->r = this->v = this->b = 0.0; }
    else {
    double i = lp->e/(d*d)*ps;
    this->r = i*kr->r*lp->c->r;
    this->v = i*kr->v*lp->c->v;
    this->b = i*kr->b*lp->c->b; }
  delete(po);
  delete(r);
  delete(l);
  delete(n);
}

void Energie::calculDiffusion(Position3D *p,Direction3D *n,Couleur *kd,LumierePonctuelle *lp) {
  Direction3D *l = new Direction3D(p,lp->p);
  double d = l->normalise();
  double ps = l->produitScalaire(n);
  if ( ps < 0.0 ) {
    r = v = b = 0.0; }
    else {
    double i = lp->e/(d*d)*ps;
    r = i*kd->r*lp->c->r;
    v = i*kd->v*lp->c->v;
    b = i*kd->b*lp->c->b; }
  delete(l);
}

void Energie::calculReflexionSpeculaire(Position3D *p,Direction3D *n,Couleur *kr,LumierePonctuelle *lp,Position3D *obs) {
  Direction3D *l = new Direction3D(p,lp->p);
  double d = l->normalise();
  Direction3D *r = l->reflexion(n);
  if ( !r ) {
    this->r = this->v = this->b = 0.0;
    delete(l);
    return; }
  Direction3D *po = new Direction3D(p,obs);
  po->normalise();
  double ps = r->produitScalaire(po);
  if ( ps < 0.0 ) {
    this->r = this->v = this->b = 0.0; }
    else {
    double i = lp->e/(d*d)*ps;
    this->r = i*kr->r*lp->c->r;
    this->v = i*kr->v*lp->c->v;
    this->b = i*kr->b*lp->c->b; }
  delete(po);
  delete(r);
  delete(l);
}