namespace Msp {
namespace Geometry {
+/**
+A shape modified by an affine transformation.
+*/
template<typename T, unsigned D>
class TransformedShape: public Shape<T, D>
{
private:
Shape<T, D> *shape;
AffineTransformation<T, D> transformation;
+ AffineTransformation<T, D> inverse_trans;
public:
TransformedShape(const Shape<T, D> &, const AffineTransformation<T, D> &);
const AffineTransformation<T, D> &get_transformation() const { return transformation; }
virtual HyperBox<T, D> get_axis_aligned_bounding_box() const;
+ virtual bool contains(const LinAl::Vector<T, D> &) const;
virtual bool check_intersection(const Ray<T, D> &) const;
+ virtual unsigned get_max_ray_intersections() const { return shape->get_max_ray_intersections(); }
+ virtual unsigned get_intersections(const Ray<T, D> &, SurfacePoint<T, D> *, unsigned) const;
};
template<typename T, unsigned D>
inline TransformedShape<T, D>::TransformedShape(const Shape<T, D> &s, const AffineTransformation<T, D> &t):
shape(s.clone()),
- transformation(t)
+ transformation(t),
+ inverse_trans(invert(t))
{ }
template<typename T, unsigned D>
inline TransformedShape<T, D>::TransformedShape(const TransformedShape &other):
shape(other.shape->clone()),
- transformation(other.transformation)
+ transformation(other.transformation),
+ inverse_trans(other.inverse_trans)
{ }
template<typename T, unsigned D>
delete shape;
shape = other.shape->clone();
transformation = other.transformation;
+ inverse_trans = other.inverse_trans;
}
template<typename T, unsigned D>
return shape->get_axis_aligned_bounding_box();
}
+template<typename T, unsigned D>
+inline bool TransformedShape<T, D>::contains(const LinAl::Vector<T, D> &point) const
+{
+ return shape->contains(inverse_trans.transform(point));
+}
+
template<typename T, unsigned D>
inline bool TransformedShape<T, D>::check_intersection(const Ray<T, D> &ray) const
{
- // TODO cache the inverse transformation for performance
- LinAl::SquareMatrix<T, D+1> inverse_trans = LinAl::invert(transformation.get_matrix());
- Ray<T, D> trans_ray(reduce_vector(inverse_trans*augment_vector(ray.get_start(), T(1))),
- reduce_vector(inverse_trans*augment_vector(ray.get_direction(), T(0))));
- return shape->check_intersection(trans_ray);
+ Ray<T, D> local_ray(inverse_trans.transform(ray.get_start()),
+ inverse_trans.transform_linear(ray.get_direction()));
+ return shape->check_intersection(local_ray);
+}
+
+template<typename T, unsigned D>
+inline unsigned TransformedShape<T, D>::get_intersections(const Ray<T, D> &ray, SurfacePoint<T, D> *points, unsigned size) const
+{
+ Ray<T, D> local_ray(inverse_trans.transform(ray.get_start()),
+ inverse_trans.transform_linear(ray.get_direction()));
+ unsigned count = shape->get_intersections(local_ray, points, size);
+ if(points)
+ {
+ for(unsigned i=0; i<count; ++i)
+ {
+ points[i].position = transformation.transform(points[i].position);
+ /* XXX This is not correct for nonuniform scaling. Inverse of the
+ transpose of the upper DxD part of the matrix should be used. */
+ points[i].normal = transformation.transform(points[i].normal);
+ }
+ }
+ return count;
}
} // namespace Geometry