X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fgeometry%2Fhyperbox.h;h=9a161f35fb0fdbc5ff604735d51eb6e1d060eeaf;hb=827b227ae53884109b6885ccd1424dda8c0b3725;hp=2ade28acddd42ba9da6eefcb8cbefe14040ee535;hpb=6ff13022b53830d35283905d562c2ef3af198cc1;p=libs%2Fmath.git

diff --git a/source/geometry/hyperbox.h b/source/geometry/hyperbox.h
index 2ade28a..9a161f3 100644
--- a/source/geometry/hyperbox.h
+++ b/source/geometry/hyperbox.h
@@ -1,13 +1,21 @@
 #ifndef MSP_GEOMETRY_HYPERBOX_H_
 #define MSP_GEOMETRY_HYPERBOX_H_
 
+#include <algorithm>
+#include <cmath>
+#include <stdexcept>
 #include <msp/linal/vector.h>
 #include "ray.h"
 #include "shape.h"
+#include "surfacepoint.h"
 
 namespace Msp {
 namespace Geometry {
 
+/**
+A shape bounded by planar faces at right angles to each other.  Two- and three-
+dimensional cases are Rectangle and Box, respectively.
+*/
 template<typename T, unsigned D>
 class HyperBox: public Shape<T, D>
 {
@@ -24,7 +32,10 @@ public:
 	T get_dimension(unsigned) const;
 
 	virtual HyperBox<T, D> get_axis_aligned_bounding_box() const { return *this; }
+	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 2; }
+	virtual unsigned get_intersections(const Ray<T, D> &, SurfacePoint<T, D> *, unsigned) const;
 };
 
 template<typename T, unsigned D>
@@ -37,7 +48,11 @@ inline HyperBox<T, D>::HyperBox()
 template<typename T, unsigned D>
 inline HyperBox<T, D>::HyperBox(const LinAl::Vector<T, D> &d):
 	dimensions(d)
-{ }
+{
+	for(unsigned i=0; i<D; ++i)
+		if(dimensions[i]<=T(0))
+			throw std::invalid_argument("HyperBox::HyperBox");
+}
 
 template<typename T, unsigned D>
 inline HyperBox<T, D> *HyperBox<T, D>::clone() const
@@ -51,26 +66,69 @@ inline T HyperBox<T, D>::get_dimension(unsigned i) const
 	return dimensions[i];
 }
 
+template<typename T, unsigned D>
+inline bool HyperBox<T, D>::contains(const LinAl::Vector<T, D> &point) const
+{
+	using std::abs;
+
+	for(unsigned i=0; i<D; ++i)
+		if(abs(point[i])>dimensions[i]/T(2))
+			return false;
+	return true;
+}
+
 template<typename T, unsigned D>
 inline bool HyperBox<T, D>::check_intersection(const Ray<T, D> &ray) const
 {
+	return get_intersections(ray, 0, 1);
+}
+
+template<typename T, unsigned D>
+inline unsigned HyperBox<T, D>::get_intersections(const Ray<T, D> &ray, SurfacePoint<T, D> *points, unsigned size) const
+{
+	using std::abs;
+
+	if(size>2)
+		size = 2;
+
 	LinAl::Vector<T, D> half_dim = dimensions/T(2);
-	for(unsigned i=0; i<D; ++i)
-		for(int j=-1; j<=1; j+=2)
+	unsigned n = 0;
+	for(unsigned i=0; (n<size && i<D); ++i)
+	{
+		if(!ray.get_direction()[i])
+			continue;
+
+		for(int j=-1; (n<size && j<=1); j+=2)
 		{
 			T x = (T(j)*half_dim[i]-ray.get_start()[i])/ray.get_direction()[i];
-			if(x>0)
+			if(!ray.check_limits(x))
+				continue;
+
+			LinAl::Vector<T, D> p = ray.get_start()+ray.get_direction()*x;
+
+			bool inside = true;
+			for(unsigned k=0; (inside && k<D); ++k)
+				inside = (k==i || abs(p[k])<=half_dim[k]);
+
+			if(inside)
 			{
-				LinAl::Vector<T, D> p = ray.get_start()+ray.get_direction()*x;
-				bool inside = true;
-				for(unsigned k=0; (inside && k<D); ++k)
-					inside = (k==i || (p[k]>=-half_dim[k] && p[k]<half_dim[k]));
-				if(inside)
-					return true;
+				if(points)
+				{
+					points[n].position = p;
+					points[n].normal = LinAl::Vector<T, D>();
+					points[n].normal[i] = j;
+					points[n].distance = x;
+
+					if(n==1 && x<points[0].distance)
+						std::swap(points[0], points[1]);
+				}
+
+				++n;
 			}
 		}
+	}
 
-	return false;
+	return n;
 }
 
 } // namespace Geometry