bool static rayIntersectsRect(const Math::Ray &ray, const Math::Vector3d &topLeft, const Math::Vector3d &topRight,
const Math::Vector3d &bottomLeft, const Math::Vector3d &bottomRight) {
// Orthogonal basis in rectangle coordinates
Math::Vector3d topRectDir = topRight - topLeft;
Math::Vector3d leftRectDir = bottomLeft - topLeft;
Math::Vector3d n = Math::Vector3d::crossProduct(topRectDir, leftRectDir);
float nDotDir = Math::Vector3d::dotProduct(n, ray.getDirection());
if (ABS(nDotDir) < 1e-6) {
// The ray is coplanar with the rectangle
return false;
}
// Solution to the system (intersection of line with plane):
// Line equation: V = ray.origin + t * ray.direction
// Plane equation: dot(n, V) = 0
float t = -Math::Vector3d::dotProduct(n, ray.getOrigin() - topLeft) / nDotDir;
if (t < 0.0) {
// The intersection is not in the ray direction
return false;
}
// Intersection point in world coordinates
Math::Vector3d intersection = ray.getOrigin() + ray.getDirection() * t;
// Intersection point in 2D rect coordinates
Math::Vector3d intersect2D = intersection - topLeft;
float u = Math::Vector3d::dotProduct(intersect2D, topRectDir);
float v = Math::Vector3d::dotProduct(intersect2D, leftRectDir);
// Intersection inside the rectangle
return (u >= 0.0 && u <= Math::Vector3d::dotProduct(topRectDir, topRectDir)
&& v >= 0.0 && v <= Math::Vector3d::dotProduct(leftRectDir, leftRectDir));
}
//-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~
//see http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?f=9&t=4152&hilit=raytest
//for reference
void
PhysicsZone::rayCast(Math::Ray _ray, Math::Real _maxDistance, I_CollisionVisitor& _visitor)
{
Math::Vector3 offset = _ray.getDirection();
offset.normalize();
offset *= _maxDistance;
Math::Point3 endpoint = _ray.getOrigin() + offset;
//(m_pZone, _ray.getOrigin().m_array, endpoint.m_array, rayCastFilter, &rayCastQuery, rayCastPrefilter);
btVector3 tquatFrom = btVector3(_ray.getOrigin().m_x,_ray.getOrigin().m_y,_ray.getOrigin().m_z);
btVector3 tquatTo = btVector3(_ray.getOrigin().m_x,_ray.getOrigin().m_y,_ray.getOrigin().m_z);
RayResultCallback resultCallback(tquatFrom,tquatTo);
m_pZone->rayTest(tquatFrom,tquatTo,resultCallback);
}
