source/geometry/hyperbox.h

   1 #ifndef MSP_GEOMETRY_HYPERBOX_H_
   2 #define MSP_GEOMETRY_HYPERBOX_H_
   3
   4 #include <msp/linal/vector.h>
   5 #include "ray.h"
   6 #include "shape.h"
   7
   8 namespace Msp {
   9 namespace Geometry {
  10
  11 template<typename T, unsigned D>
  12 class HyperBox: public Shape<T, D>
  13 {
  14 private:
  15         LinAl::Vector<T, D> dimensions;
  16
  17 public:
  18         HyperBox();
  19         explicit HyperBox(const LinAl::Vector<T, D> &);
  20
  21         virtual HyperBox *clone() const;
  22
  23         const LinAl::Vector<T, D> &get_dimensions() const { return dimensions; }
  24         T get_dimension(unsigned) const;
  25
  26         virtual HyperBox<T, D> get_axis_aligned_bounding_box() const { return *this; }
  27         virtual bool check_intersection(const Ray<T, D> &) const;
  28 };
  29
  30 template<typename T, unsigned D>
  31 inline HyperBox<T, D>::HyperBox()
  32 {
  33         for(unsigned i=0; i<D; ++i)
  34                 dimensions[i] = 1;
  35 }
  36
  37 template<typename T, unsigned D>
  38 inline HyperBox<T, D>::HyperBox(const LinAl::Vector<T, D> &d):
  39         dimensions(d)
  40 { }
  41
  42 template<typename T, unsigned D>
  43 inline HyperBox<T, D> *HyperBox<T, D>::clone() const
  44 {
  45         return new HyperBox<T, D>(dimensions);
  46 }
  47
  48 template<typename T, unsigned D>
  49 inline T HyperBox<T, D>::get_dimension(unsigned i) const
  50 {
  51         return dimensions[i];
  52 }
  53
  54 template<typename T, unsigned D>
  55 inline bool HyperBox<T, D>::check_intersection(const Ray<T, D> &ray) const
  56 {
  57         LinAl::Vector<T, D> half_dim = dimensions/T(2);
  58         for(unsigned i=0; i<D; ++i)
  59                 for(int j=-1; j<=1; j+=2)
  60                 {
  61                         T x = (T(j)*half_dim[i]-ray.get_start()[i])/ray.get_direction()[i];
  62                         if(x>0)
  63                         {
  64                                 LinAl::Vector<T, D> p = ray.get_start()+ray.get_direction()*x;
  65                                 bool inside = true;
  66                                 for(unsigned k=0; (inside && k<D); ++k)
  67                                         inside = (k==i || (p[k]>=-half_dim[k] && p[k]<half_dim[k]));
  68                                 if(inside)
  69                                         return true;
  70                         }
  71                 }
  72
  73         return false;
  74 }
  75
  76 } // namespace Geometry
  77 } // namespace Msp
  78
  79 #endif