bool Light::intersects(const Point &p) const
{
Intersection i = world->intersect(Ray(origin, p - origin));
const PrimitiveModel *model = i.getModel();
if ((model) && (model->normalAt(p) * (origin - p) < 0))
{
return false;
}
return i.getPoint().near(p);
}
/**
* Computes the first intersection between a ray and all
* the Objects of the scene.
* @param ray the ray to be intersected
* @param intersection the first intersection computed if
* there is one
* @return true if there is an intersection, false otherwise.
**/
bool Scene::intersect(const ray::Ray & ray,
scene::Intersection & intersection)
{
bool isIntersected=false;
float minDistance=INFINITY;
Intersection interTest;
for(iterator_object it=_objects.begin();
it!=_objects.end();++it)
{
if((*it)->intersect(ray,interTest))
{
float currentDistance=glm::distance2(interTest.getPoint(),
ray.getOrigin());
if(currentDistance<minDistance)
{
isIntersected=true;
minDistance=currentDistance;
intersection=interTest;
}
}
}
return isIntersected;
}
Colour* rayTrace(const Colour& ambient, const Point3D& eye, Ray ray, SceneNode* root,
const std::list<Light*>& lights, int level, double fogDist){
if(level <= 0)
return NULL;
Intersection* i = root->intersect(ray);
bool fogOn = true;
if(fogDist <= 0)
fogOn = false;
if(i != NULL){
Colour color(0,0,0);
Colour fog(0.8,0.8,0.8);
Colour diffuse(0,0,0), specular(0,0,0);
Material* material = i->getMaterial();
Vector3D n = i->getNormal();
n.normalize();
Point3D p = i->getPoint();
Vector3D v = eye - p;
v.normalize();
for (std::list<Light*>::const_iterator I = lights.begin(); I != lights.end(); ++I) {
Light light = **I;
Vector3D l = light.position - p;
l.normalize();
Vector3D r = 2*l*n*n - l;
r.normalize();
// shadows
Ray lightRay = Ray(p, l);
Intersection* lightIsc = root->intersect(lightRay);
if(lightIsc == NULL){
// add light contribution
//std::cerr << "light" << std::endl;
if(n*l > 0)
diffuse = diffuse + material->getDiffuse() * (l*n) * light.colour;
if(r*v > 0)
specular = specular + material->getSpecular() * pow((r*v), material->getShininess()) * light.colour;
}
}
//secondaty rays
Vector3D r = 2*v*n*n - v;
r.normalize();
Ray refRay(p, r);
Colour* reflectedColor = rayTrace(ambient, eye, refRay, root, lights, level-1, fogDist);
if(reflectedColor != NULL){
if(n*r > 0)
diffuse = diffuse + material->getDiffuse() * (r*n) * material->getReflectivity() * (*reflectedColor);
if(r*v > 0)
specular = specular + material->getSpecular() * pow((r*v), material->getShininess()) * material->getReflectivity() * (*reflectedColor);
}
color = ambient*material->getColor() + diffuse + specular;
if(fogOn){
double dist = i->getT()/fogDist;
if(dist>1)
dist=1;
color = (1-dist)*color + dist*fog;
}
return new Colour(color);
}
return NULL;
}
Intersection Cylindre::intersect(Rayon* r)
{
Intersection inter;
double a;
double b;
double c;
double delta;
double t, t1, t2;
/* equation du Cylindre y²+z²=rayon² avec 0<x<longueur=height
* (dy.t+py)²+(dz.t+pz)²=rayon²
* (dy²+dz²)t²+(dy.py+dz.pz)t+(py²+pz²-rayon²)=0
* at²+bt+c=0
*/
inter.setObjet(this);
a=pow(r->getDirection().y,2)+pow(r->getDirection().z,2);
b=(r->getDirection().y*r->getPosition().y)+(r->getDirection().z*r->getPosition().z);
c=pow(r->getPosition().y,2)+pow(r->getPosition().z,2)-pow(this->r,2);
//calcul du discriminant
delta = pow(b,2)-4*a*c;
if (delta <= 0) {
inter.setDistance(DBL_MAX); //distance infinie (pas d'intersection)
//si py²+pz²-rayon²<=0 ou c<0
//on se situe sur l'alignement du cylindre
if(c<0){
if( (this->height!=0)
&& (r->getPosition().x>this->height
|| (r->getPosition().x>=0.0 && r->getPosition().x<this->height))){
if(r->getDirection().x!=0.0){
t = (this->height-r->getPosition().x)/r->getDirection().x;
inter.setPoint( vector3(this->height,
t * r->getDirection().y + r->getPosition().y,
t * r->getDirection().z + r->getPosition().z) );
if(t>EPSILON && c<=0){
inter.setDistance ( (inter.getPoint()-r->getPosition()).Length() );
}else{
inter.setDistance(DBL_MAX);
}
}else{
inter.setDistance ( DBL_MAX );
}
}
if( (this->height!=0)
&& (r->getPosition().x<this->height
|| (r->getPosition().x>0.0 && r->getPosition().x<=this->height))){
if(r->getDirection().x!=0.0){
t = (-r->getPosition().x)/r->getDirection().x;
inter.setPoint(vector3(0.0,
t * r->getDirection().y + r->getPosition().y,
t * r->getDirection().z + r->getPosition().z) );
if(t>EPSILON && c<=0){
inter.setDistance ( (inter.getPoint()-r->getPosition()).Length() );
}else{
inter.setDistance(DBL_MAX);
}
}else{
inter.setDistance(DBL_MAX);
}
}
}
}else{ //deux solutions
t1 = (-b + sqrt (delta)) / 2*a;
t2 = (-b - sqrt (delta)) / 2*a;
if (t1 <= EPSILON && t2 <= EPSILON){
inter.setDistance(DBL_MAX);
}else{
if ((t1 <= t2 && t1 > EPSILON) || (t2 < t1 && t2 < EPSILON)){
t = t1;
}else if ((t2 < t1 && t2 > EPSILON) || (t1 < t2 && t1 < EPSILON)){
t = t2;
}
inter.setPoint(vector3(t * r->getDirection().x + r->getPosition().x,
t * r->getDirection().x + r->getPosition().x,
t * r->getDirection().z + r->getPosition().z));
inter.setDistance ( (inter.getPoint()-r->getPosition()).Length() );
if( (this->height!=0) && (inter.getPoint().x>this->height)
|| (r->getPosition().x>this->height && c<=0)){
if(r->getDirection().x!=0.0){
t = (this->height-r->getPosition().x)/r->getDirection().x;
inter.setPoint(vector3(this->height,
t * r->getDirection().y + r->getPosition().y,
t * r->getDirection().z + r->getPosition().z) );
if(t>EPSILON && c<=0){
inter.setDistance ( (inter.getPoint()-r->getPosition()).Length() );
}else{
inter.setDistance(DBL_MAX);
}
}else{
inter.setDistance(DBL_MAX);
}
}
if( (this->height!=0)
&& (inter.getPoint().x<0.0)
|| (r->getPosition().x<0.0 && c<=0)){
if(r->getDirection().x!=0.0){
t = (-r->getPosition().x)/r->getDirection().x;
inter.setPoint(vector3(0.0,
t * r->getDirection().y + r->getPosition().y,
t * r->getDirection().z + r->getPosition().z) );
if(t>EPSILON){
inter.setDistance ( (inter.getPoint()-r->getPosition()).Length() );
}else{
inter.setDistance(DBL_MAX);
}
}else{
inter.setDistance(DBL_MAX);
}
}
}
}
//TODO: la normale
return (inter);
}
