From d9192270b603228c5d57a207b854a36d795d930c Mon Sep 17 00:00:00 2001
From: unknown <p265186@012987.(none)>
Date: Thu, 15 Mar 2012 16:52:54 +0100
Subject: [PATCH] Added callback function to Raycast, which is used to
 determine when a ray should stop.

---
 library/PolyVoxCore/include/PolyVoxCore/Raycast.h   | 4 +++-
 library/PolyVoxCore/include/PolyVoxCore/Raycast.inl | 5 +++--
 tests/TestRaycast.cpp                               | 7 ++++++-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/library/PolyVoxCore/include/PolyVoxCore/Raycast.h b/library/PolyVoxCore/include/PolyVoxCore/Raycast.h
index b559834a..cb559ec2 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/Raycast.h
+++ b/library/PolyVoxCore/include/PolyVoxCore/Raycast.h
@@ -96,7 +96,7 @@ namespace PolyVox
 	{
 	public:
 		///Constructor
-		Raycast(VolumeType<VoxelType>* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dDirectionAndLength, RaycastResult& result);
+		Raycast(VolumeType<VoxelType>* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dDirectionAndLength, RaycastResult& result, polyvox_function<bool(const typename VolumeType<VoxelType>::Sampler& sampler)> funcIsPassable);
 
 		///Sets the start position for the ray.
 		void setStart(const Vector3DFloat& v3dStart);
@@ -109,6 +109,8 @@ namespace PolyVox
 	private:
 		RaycastResult& m_result;
 
+		polyvox_function<bool(const typename VolumeType<VoxelType>::Sampler& position)> m_funcIsPassable;
+
 		void doRaycast(float x1, float y1, float z1, float x2, float y2, float z2);
 
 		VolumeType<VoxelType>* m_volData;
diff --git a/library/PolyVoxCore/include/PolyVoxCore/Raycast.inl b/library/PolyVoxCore/include/PolyVoxCore/Raycast.inl
index 11a14cb1..a2e12668 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/Raycast.inl
+++ b/library/PolyVoxCore/include/PolyVoxCore/Raycast.inl
@@ -32,12 +32,13 @@ namespace PolyVox
 	/// \param result An instance of RaycastResult in which the result will be stored.
 	////////////////////////////////////////////////////////////////////////////////
 	template< template<typename> class VolumeType, typename VoxelType>
-	Raycast<VolumeType, VoxelType>::Raycast(VolumeType<VoxelType>* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dDirectionAndLength, RaycastResult& result)
+	Raycast<VolumeType, VoxelType>::Raycast(VolumeType<VoxelType>* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dDirectionAndLength, RaycastResult& result, polyvox_function<bool(const typename VolumeType<VoxelType>::Sampler& sampler)> funcIsPassable)
 		:m_result(result)
 		,m_volData(volData)
 		,m_sampVolume(volData)
 		,m_v3dStart(v3dStart)
 		,m_v3dDirectionAndLength(v3dDirectionAndLength)
+		,m_funcIsPassable(funcIsPassable)
 	{
 	}
 
@@ -139,7 +140,7 @@ namespace PolyVox
 
 		for(;;)
 		{
-			if(m_sampVolume.getVoxel().getDensity() > VoxelType::getThreshold())
+			if(!m_funcIsPassable(m_sampVolume))
 			{
 				m_result.foundIntersection = true;
 				m_result.intersectionVoxel = Vector3DInt32(i,j,k);
diff --git a/tests/TestRaycast.cpp b/tests/TestRaycast.cpp
index e523da4a..39d53705 100644
--- a/tests/TestRaycast.cpp
+++ b/tests/TestRaycast.cpp
@@ -33,6 +33,11 @@ freely, subject to the following restrictions:
 
 using namespace PolyVox;
 
+bool isPassableByRay(const SimpleVolume<Density8>::Sampler& sampler)
+{
+	return sampler.getVoxel().getDensity() < Density8::getThreshold();
+}
+
 void TestRaycast::testExecute()
 {
 	const int32_t uVolumeSideLength = 32;
@@ -67,7 +72,7 @@ void TestRaycast::testExecute()
 	for(int ct = 0; ct < 1000000; ct++)
 	{
 		RaycastResult result;
-		Raycast<SimpleVolume, Density8> raycast(&volData, start, randomUnitVectors[ct % 1024] * 1000.0f, result);
+		Raycast<SimpleVolume, Density8> raycast(&volData, start, randomUnitVectors[ct % 1024] * 1000.0f, result, isPassableByRay);
 		raycast.execute();
 		if(result.foundIntersection)
 		{