From 7919982691f0b8c69d8bef1bf6471b1e7a312163 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 2 Jul 2016 18:06:27 +0300
Subject: [PATCH] Add an entry flag to SharedPoint

---
 source/geometry/extrudedshape.h | 2 ++
 source/geometry/halfspace.h     | 1 +
 source/geometry/hyperbox.h      | 1 +
 source/geometry/hypersphere.h   | 1 +
 source/geometry/negation.h      | 3 +++
 source/geometry/surfacepoint.h  | 1 +
 6 files changed, 9 insertions(+)

diff --git a/source/geometry/extrudedshape.h b/source/geometry/extrudedshape.h
index 84addc4..a62aa9a 100644
--- a/source/geometry/extrudedshape.h
+++ b/source/geometry/extrudedshape.h
@@ -147,6 +147,7 @@ inline unsigned ExtrudedShape<T, D>::get_intersections(const Ray<T, D> &ray, Sur
 					points[n].position = ray_start+ray_direction*x;
 					points[n].normal = compose(base_points[i].normal, T(0));
 					points[n].distance = x;
+					points[n].entry = base_points[i].entry;
 				}
 
 				++n;
@@ -173,6 +174,7 @@ inline unsigned ExtrudedShape<T, D>::get_intersections(const Ray<T, D> &ray, Sur
 					points[n].normal = LinAl::Vector<T, D>();
 					points[n].normal[D-1] = i;
 					points[n].distance = x;
+					points[n].entry = (T(i)*ray_direction[D-1]<T(0));
 				}
 
 				++n;
diff --git a/source/geometry/halfspace.h b/source/geometry/halfspace.h
index 518f91a..b439851 100644
--- a/source/geometry/halfspace.h
+++ b/source/geometry/halfspace.h
@@ -76,6 +76,7 @@ inline unsigned HalfSpace<T, D>::get_intersections(const Ray<T, D> &ray, Surface
 			points[0].position = ray.get_start()+ray.get_direction()*x;
 			points[0].normal = normal;
 			points[0].distance = x;
+			points[0].entry = (c<T(0));
 		}
 
 		return 1;
diff --git a/source/geometry/hyperbox.h b/source/geometry/hyperbox.h
index e45fadc..546ad0e 100644
--- a/source/geometry/hyperbox.h
+++ b/source/geometry/hyperbox.h
@@ -116,6 +116,7 @@ inline unsigned HyperBox<T, D>::get_intersections(const Ray<T, D> &ray, SurfaceP
 					points[n].normal = LinAl::Vector<T, D>();
 					points[n].normal[i] = j;
 					points[n].distance = x;
+					points[n].entry = (T(j)*ray.get_direction()[i]<T(0));
 
 					if(n==1 && x<points[0].distance)
 						std::swap(points[0], points[1]);
diff --git a/source/geometry/hypersphere.h b/source/geometry/hypersphere.h
index 4df03fe..6bb4352 100644
--- a/source/geometry/hypersphere.h
+++ b/source/geometry/hypersphere.h
@@ -85,6 +85,7 @@ inline unsigned HyperSphere<T, D>::get_intersections(const Ray<T, D> &ray, Surfa
 				points[n].position = ray.get_start()+ray.get_direction()*x;
 				points[n].normal = normalize(points[n].position);
 				points[n].distance = x;
+				points[n].entry = (i<0);
 			}
 
 			++n;
diff --git a/source/geometry/negation.h b/source/geometry/negation.h
index ce2f787..8e2b3f4 100644
--- a/source/geometry/negation.h
+++ b/source/geometry/negation.h
@@ -79,7 +79,10 @@ inline unsigned Negation<T, D>::get_intersections(const Ray<T, D> &ray, SurfaceP
 {
 	unsigned count = shape->get_intersections(ray, points, size);
 	for(unsigned i=0; i<count; ++i)
+	{
 		points[i].normal = -points[i].normal;
+		points[i].entry = !points[i].entry;
+	}
 	return count;
 }
 
diff --git a/source/geometry/surfacepoint.h b/source/geometry/surfacepoint.h
index 57a66d1..3b38e1d 100644
--- a/source/geometry/surfacepoint.h
+++ b/source/geometry/surfacepoint.h
@@ -16,6 +16,7 @@ struct SurfacePoint
 	LinAl::Vector<T, N> position;
 	LinAl::Vector<T, N> normal;
 	T distance;
+	bool entry;
 };
 
 template<typename T, unsigned N>
-- 
2.43.0