bool
prSphere::Hits(const Ray &r) const
{
const vec3 vec = r.pos-mCenter;
const real b = -vec.dot(r.dir);
real det = Square(b) - r.dir.dot(r.dir) * vec.sqr_length() + mSqrRadius;
if (det > real(0)) {
det = det.Sqrt();
const real
i1 = b - det,
i2 = b + det;
if (i2 > r.minDist) {
if (mMaterialFront && i1 < r.dist && i1 > r.minDist) {
return true;
} else if (mMaterialBack && i2 < r.dist) {
return true;
}
}
}
return false;
}
void
prSphere::Intersect(Ray &r) const
{
const vec3 vec = r.pos-mCenter;
const real b = -vec.dot(r.dir);
real det = Square(b) - r.dir.dot(r.dir) * vec.sqr_length() + mSqrRadius;
if (det > real(0)) {
det = det.Sqrt();
const real i1 = b - det;
const real i2 = b + det;
if (i2 > r.minDist) {
if (mMaterialFront && i1 < r.dist && i1 > r.minDist) {
//outside
r.gState.object = this;
r.dist = i1;
} else if (mMaterialBack && i2 < r.dist) {
//inside
r.gState.object = this;
r.dist = i2;
}
return;
}
}
}
