bool intersect(CRay& _ray, float* _thit, CLocalGeo* _local, int& _id) {
if (_ray.m_id == m_id)
return false;
V3f E1 = m_V0 - m_V1;
V3f E2 = m_V0 - m_V2;
V3f S = m_V0 - _ray.m_pos;
float d = det(_ray.m_dir, E1, E2);
if (d < EPS && d > -EPS)
return false;
float d1 = det(S, E1, E2);
float t = d1 / d;
if (t < _ray.m_t_min || t > _ray.m_t_max)
return false;
float d2 = det(_ray.m_dir, S, E2);
float beta = d2 / d;
if (beta < -EPS || beta - 1 > EPS)
return false;
float d3 = det(_ray.m_dir, E1, S);
float gamma = d3 / d;
if (gamma < -EPS || gamma - 1 > EPS || beta + gamma - 1 > EPS)
return false;
*_thit = t;
_id = m_id;
_local->m_pos = _ray.Ray_t(t);
_local->m_n = (m_V0-m_V1).cross(m_V0-m_V2);
_local->m_n = _local->m_n / _local->m_n.norm();
return true;
}
bool intersect(CRay& _ray, float* _thit, CLocalGeo* _local, int& _id) {
if (_ray.m_id == m_id)
return false;
float t;
V3f oc = _ray.m_pos - m_c;
float a = _ray.m_dir.dot(_ray.m_dir); // dir should be unit
float b = _ray.m_dir.dot(oc);
float c = oc.dot(oc) - m_r2;
float delta = b * b - a * c;
if (delta < 0) // no solution
return false;
else if (delta > -EPS && delta < EPS) { // one solution
t = - b / a;
if (t > _ray.m_t_max || t < _ray.m_t_min) // out of range
return false;
} else { // two solutions
float deltasqrt = sqrt(delta);
float t1 = (- b - deltasqrt) / a;
float t2 = (- b + deltasqrt) / a;
bool flag = false;
t = _ray.m_t_max;
if (t1 <= _ray.m_t_max && t1 >= _ray.m_t_min) {
flag = true;
t = min(t, t1);
}
if (t2 <= _ray.m_t_max && t2 >= _ray.m_t_min) {
flag = true;
t = min(t, t2);
}
if (!flag) // both out of range
return false;
}
// pass t, compute CLocalGeo
*_thit = t;
_id = m_id;
_local->m_pos = _ray.Ray_t(t);
_local->m_n = _local->m_pos - m_c;
_local->m_n = _local->m_n / _local->m_n.norm();
return true;
}