source/geometry/hypersphere.h

   1 #ifndef MSP_GEOMETRY_HYPERSPHERE_H_
   2 #define MSP_GEOMETRY_HYPERSPHERE_H_
   3
   4 #include <msp/linal/vector.h>
   5 #include "hyperbox.h"
   6 #include "ray.h"
   7 #include "shape.h"
   8
   9 namespace Msp {
  10 namespace Geometry {
  11
  12 template<typename T, unsigned D>
  13 class HyperSphere: public Shape<T, D>
  14 {
  15 private:
  16         T radius;
  17
  18 public:
  19         HyperSphere();
  20         explicit HyperSphere(T);
  21
  22         virtual HyperSphere *clone() const;
  23
  24         T get_radius() const { return radius; }
  25
  26         virtual HyperBox<T, D> get_axis_aligned_bounding_box() const;
  27         virtual bool check_intersection(const Ray<T, D> &) const;
  28 };
  29
  30 template<typename T, unsigned D>
  31 inline HyperSphere<T, D>::HyperSphere():
  32         radius(1)
  33 { }
  34
  35 template<typename T, unsigned D>
  36 inline HyperSphere<T, D>::HyperSphere(T r):
  37         radius(r)
  38 { }
  39
  40 template<typename T, unsigned D>
  41 inline HyperSphere<T, D> *HyperSphere<T, D>::clone() const
  42 {
  43         return new HyperSphere<T, D>(radius);
  44 }
  45
  46 template<typename T, unsigned D>
  47 inline HyperBox<T, D> HyperSphere<T, D>::get_axis_aligned_bounding_box() const
  48 {
  49         LinAl::Vector<T, D> dimensions;
  50         for(unsigned i=0; i<D; ++i)
  51                 dimensions[i] = radius;
  52         return HyperBox<T, D>(dimensions);
  53 }
  54
  55 template<typename T, unsigned D>
  56 inline bool HyperSphere<T, D>::check_intersection(const Ray<T, D> &ray) const
  57 {
  58         T x = inner_product(ray.get_direction(), ray.get_start());
  59         if(x>0)
  60                 return inner_product(ray.get_start(), ray.get_start())<=radius*radius;
  61         else
  62         {
  63                 LinAl::Vector<T, D> nearest = ray.get_start()-ray.get_direction()*x;
  64                 return inner_product(nearest, nearest)<=radius*radius;
  65         }
  66 }
  67
  68 } // namespace Geometry
  69 } // namespace Msp
  70
  71 #endif