source/geometry/negation.h

   1 #ifndef MSP_GEOMETRY_NEGATION_H_
   2 #define MSP_GEOMETRY_NEGATION_H_
   3
   4 #include "shape.h"
   5
   6 namespace Msp {
   7 namespace Geometry {
   8
   9 /**
  10 Negates a shape.  Not particulary useful on its own, but can be used together
  11 with Intersection to cut holes.
  12 */
  13 template<typename T, unsigned D>
  14 class Negation: public Shape<T, D>
  15 {
  16 private:
  17         Shape<T, D> *shape;
  18
  19 public:
  20         Negation(const Shape<T, D> &);
  21         Negation(const Negation &);
  22         Negation &operator=(const Negation &);
  23         ~Negation();
  24
  25         virtual Negation *clone() const;
  26
  27         const Shape<T, D> &get_shape() const { return *shape; }
  28
  29         virtual BoundingBox<T, D> get_axis_aligned_bounding_box(unsigned = 0) const;
  30         virtual bool contains(const LinAl::Vector<T, D> &) const;
  31         virtual unsigned get_max_ray_intersections() const { return shape->get_max_ray_intersections(); }
  32         virtual unsigned get_intersections(const Ray<T, D> &, SurfacePoint<T, D> *, unsigned) const;
  33         virtual Coverage get_coverage(const BoundingBox<T, D> &) const;
  34 };
  35
  36 template<typename T, unsigned D>
  37 inline Negation<T, D>::Negation(const Shape<T, D> &s):
  38         shape(s.clone())
  39 { }
  40
  41 template<typename T, unsigned D>
  42 inline Negation<T, D>::Negation(const Negation<T, D> &other):
  43         shape(other.shape->clone())
  44 { }
  45
  46 template<typename T, unsigned D>
  47 inline Negation<T, D> &Negation<T, D>::operator=(const Negation<T, D> &other)
  48 {
  49         delete shape;
  50         shape = other.shape->clone();
  51         return *this;
  52 }
  53
  54 template<typename T, unsigned D>
  55 inline Negation<T, D>::~Negation()
  56 {
  57         delete shape;
  58 }
  59
  60 template<typename T, unsigned D>
  61 inline Negation<T, D> *Negation<T, D>::clone() const
  62 {
  63         return new Negation<T, D>(*shape);
  64 }
  65
  66 template<typename T, unsigned D>
  67 inline BoundingBox<T, D> Negation<T, D>::get_axis_aligned_bounding_box(unsigned detail) const
  68 {
  69         return ~shape->get_axis_aligned_bounding_box(detail);
  70 }
  71
  72 template<typename T, unsigned D>
  73 inline bool Negation<T, D>::contains(const LinAl::Vector<T, D> &point) const
  74 {
  75         return !shape->contains(point);
  76 }
  77
  78 template<typename T, unsigned D>
  79 inline unsigned Negation<T, D>::get_intersections(const Ray<T, D> &ray, SurfacePoint<T, D> *points, unsigned size) const
  80 {
  81         unsigned count = shape->get_intersections(ray, points, size);
  82         for(unsigned i=0; i<count; ++i)
  83         {
  84                 points[i].normal = -points[i].normal;
  85                 points[i].entry = !points[i].entry;
  86         }
  87         return count;
  88 }
  89
  90 template<typename T, unsigned D>
  91 inline Coverage Negation<T, D>::get_coverage(const BoundingBox<T, D> &bbox) const
  92 {
  93         Coverage coverage = shape->get_coverage(bbox);
  94         if(coverage==FULL_COVERAGE)
  95                 return NO_COVERAGE;
  96         else if(coverage==NO_COVERAGE)
  97                 return FULL_COVERAGE;
  98         else
  99                 return coverage;
 100 }
 101
 102 } // namespace Geometry
 103 } // namespace Msp
 104
 105 #endif