#include "Sphere.hxx"
Sphere::Sphere(const Vec3f& center, float radius, Shader* shader)
- : Primitive(shader),
+ : Primitive(shader),
m_center(center),
m_radius(radius)
{
if( B*B-4*A*C < 0 )
return false;
-
+
float root = sqrtf(B*B-4*A*C);
float t = (-B-root)/(2.0f*A);
if(t > ray.t())
return false;
-
- if( t < 1e-6 )
+
+ if( t < Epsilon )
{
t = (-B+root)/(2.0f*A);
- if( t < 1e-6 || t > ray.t())
+ if( t < Epsilon || t > ray.t())
return false;
}
+
ray.setT(t);
+ ray.setHit(this);
+
return true;
}
Vec3f
Sphere::GetNormal(Ray& ray)
{
- // We don't want to modify the ray (probably this is not needed, but I am
- // too lazy to think about it now ...)
- Ray tempRay = ray;
+ Vec3f p = ray.origin()+ray.direction()*ray.t();
+ Vec3f N = (p-m_center);
+ N.normalize();
- // Surface normal is the difference between intersection and center point
- if(Intersect(tempRay)) {
- // intersection point
- Vec3f i = tempRay.origin() + tempRay.direction() * (tempRay.t() - Epsilon);
- // normal
- Vec3f n = (i - m_center);
- n.normalize();
- return n;
- } else {
- // no intersection with ray, so no surface normal
- return Vec3f(0,0,0);
- }
+ return N;
}