namespace Geometry {
/**
-An infinite shape consisting of the space on one side of a plane. Mostly
-useful when composited with other shapes.
+An unbounded shape consisting of the space on one side of a plane. Mostly
+useful when intersected with other shapes.
*/
template<typename T, unsigned D>
class HalfSpace: public Shape<T, D>
const LinAl::Vector<T, D> &get_normal() const { return normal; }
- virtual HyperBox<T, D> get_axis_aligned_bounding_box() const;
+ virtual BoundingBox<T, D> get_axis_aligned_bounding_box() const;
virtual bool contains(const LinAl::Vector<T, D> &) const;
virtual unsigned get_max_ray_intersections() const { return 1; }
virtual unsigned get_intersections(const Ray<T, D> &, SurfacePoint<T, D> *, unsigned) const;
template<typename T, unsigned D>
inline HalfSpace<T, D>::HalfSpace()
{
- normal[0] = 1;
+ normal[0] = T(1);
}
template<typename T, unsigned D>
}
template<typename T, unsigned D>
-inline HyperBox<T, D> HalfSpace<T, D>::get_axis_aligned_bounding_box() const
+inline BoundingBox<T, D> HalfSpace<T, D>::get_axis_aligned_bounding_box() const
{
- // XXX Implement this properly
- return HyperBox<T, D>();
+ // XXX If the normal is aligned to an axis, should the bounding box reflect that?
+ return ~BoundingBox<T, D>();
}
template<typename T, unsigned D>
inline bool HalfSpace<T, D>::contains(const LinAl::Vector<T, D> &point) const
{
- return inner_product(point, normal)<=0;
+ return inner_product(point, normal)<=T(0);
}
template<typename T, unsigned D>
inline unsigned HalfSpace<T, D>::get_intersections(const Ray<T, D> &ray, SurfacePoint<T, D> *points, unsigned size) const
{
- T x = -inner_product(ray.get_start(), normal)/inner_product(ray.get_direction(), normal);
+ T d = inner_product(ray.get_start(), normal);
+ T c = inner_product(ray.get_direction(), normal);
+ if(c==T(0))
+ return 0;
+
+ T x = -d/c;
if(ray.check_limits(x))
{
if(points && size>0)
points[0].position = ray.get_start()+ray.get_direction()*x;
points[0].normal = normal;
points[0].distance = x;
+ points[0].entry = (c<T(0));
}
return 1;