1 files changed, 50 insertions, 0 deletions
diff --git a/Runtime/Utilities/SpatialHash.h b/Runtime/Utilities/SpatialHash.h
new file mode 100644
index 0000000..74dd01e
--- /dev/null
+++ b/Runtime/Utilities/SpatialHash.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include "Runtime/Geometry/Plane.h"
+#include "Runtime/Utilities/dynamic_array.h"
+#include "Runtime/Utilities/dense_hash_map.h"
+#include <algorithm>
+
+static const float kVoxelHeightMultiplier = 4.f;
+
+struct PlaneData
+{
+			PlaneData () {}
+			PlaneData (const Plane& plane, int colliderInstanceID, int rigidBodyOrColliderInstanceID)
+			:	m_Plane (plane)
+			,	m_ColliderInstanceID (colliderInstanceID)
+			,	m_RigidBodyOrColliderInstanceID (rigidBodyOrColliderInstanceID)
+			{}
+	Plane	m_Plane;
+	int		m_ColliderInstanceID;
+	int		m_RigidBodyOrColliderInstanceID;
+};
+
+// Collision plane cache using the google dense hashmap
+class PlaneColliderCache_dense_hashmap
+{
+public:
+	PlaneColliderCache_dense_hashmap ();
+	~PlaneColliderCache_dense_hashmap () {Clear();}
+	int Size () const { return m_PlaneHashMap.size(); };
+	bool Find (const Vector3f& pos, const Vector3f& dir, Plane& plane, int& colliderInstanceID, int& rigidBodyOrColliderInstanceID, float voxelSize) const;
+	bool Replace (const Vector3f& pos, const Vector3f& dir, const Plane& plane, int colliderInstanceID, int rigidBodyOrColliderInstanceID, float voxelSize);
+	void Clear ()
+	{
+		m_PlaneHashMap.clear ();
+	}
+private:
+	// Hash map for cached planes
+	struct UInt64HashFunctor
+	{
+		inline size_t operator ()(UInt64 x) const
+		{
+			return int(x >> 32);
+		}
+	};
+	typedef std::pair<const UInt64, PlaneData> KeyToPlanePair;
+	typedef dense_hash_map<UInt64, PlaneData, UInt64HashFunctor, std::equal_to<UInt64>, STL_ALLOCATOR (kMemSTL, KeyToPlanePair) > PlaneHashMap;
+	PlaneHashMap m_PlaneHashMap;	
+};
+
+typedef PlaneColliderCache_dense_hashmap PlaneColliderCache;