src/rcrt/primitives/Sphere.cpp

Go to the documentation of this file.

#include "Sphere.h"
#include <limits>
#include <cmath>
#include <iostream>

using namespace std;

namespace rcrt
{


Sphere::Sphere(const Point3D& c, float r, SolidObject* parent):Primitive(parent),center(c),radius(r)
{
        box.extend(center+Vec3D(radius,radius,radius));
        box.extend(center-Vec3D(radius,radius,radius));
}


Sphere::Sphere(const Sphere& s, SolidObject* parent):Primitive(parent)
{
        assign(s);
}


Sphere::~Sphere()
{
}


void Sphere::assign(const Sphere& s)
{
        center = s.center;
        radius = s.radius;
}

Intersection Sphere::intersect(Ray& ray) const
{       
        Vec3D v = ray.org() - center;
        float b = -( v * ray.dir());
        float det = (b * b) - v * v  + radius * radius;
        if (det <= 0)
                return Intersection();
        else {
                det = sqrt( det );
                float i1 = b - det;
                float i2 = b + det;
                if (i2 <= 0)
                        return Intersection();
                else {
                        if (i1 < 0) 
                        {
                                Point3D hitP(ray.atDistance(i2));
                                Vec3D vec = (hitP-center).normalize();
                                float theta = acos(vec.z());
                                float phi = atan2(vec.y(),vec.x());
                                if(phi < 0)
                                        phi += 2*M_PI;
                                Intersection is(i2, this, hitP, theta, phi, true);
                                is.setSNormalL(vec);
                            is.setGNormalL(vec);
                            return is;
                        }
                        else
                        {
                                Point3D hitP(ray.atDistance(i1));
                                Vec3D vec = (hitP-center).normalize();
                                float theta = acos(vec.z());
                                float phi = atan2(vec.y(),vec.x());
                                if(phi < 0)
                                        phi += 2*M_PI;
                                Intersection is(i1, this, hitP, theta, phi, false);
                                is.setSNormalL(vec);
                            is.setGNormalL(vec);
                            return is;
                        }
                }
        }
}


const AABB& Sphere::getBoundingBox() const
{
        return box;
}


const Point3D& Sphere::getCentroid() const
{
        return center;
}

float Sphere::getRadius() const
{
        return radius;
}

Vec3D Sphere::getSNormal(float theta, float phi) const
{
        return getGNormal(theta, phi);
}

Vec3D Sphere::getGNormal(float theta, float phi) const
{
        Vec3D no(cos(phi) * sin(theta),
        sin(phi) * sin(theta),
        cos(theta));
        no.normalize();
        return no;
}

Point2D Sphere::getUV(float theta, float phi) const
{
        return Point2D(phi/(2*M_PI), theta/M_PI);
}

AABB Sphere::clipBox(AABB& cbox) const {
        return getBoundingBox();
}

}

---