From f655eff89f5116f33ec8e93ecf8b11d81a3148b4 Mon Sep 17 00:00:00 2001
From: "erwin.coumans" <erwin.coumans@08e121b0-ae19-0410-a57b-3be3395fd4fd>
Date: Fri, 29 Aug 2008 05:39:17 +0000
Subject: [PATCH] add support for premade aabb in
 btStridingMeshInterface/btBvhTriangleMeshShape, Thanks Roy Eltham,
 http://code.google.com/p/bullet/issues/detail?id=70

---
 .../CollisionShapes/btBvhTriangleMeshShape.cpp |  9 ++++++++-
 .../CollisionShapes/btStridingMeshInterface.h  |  4 ++++
 .../btTriangleIndexVertexArray.cpp             | 18 ++++++++++++++++++
 .../btTriangleIndexVertexArray.h               | 12 +++++++++---
 .../CollisionShapes/btTriangleMeshShape.cpp    |  9 ++++++++-
 5 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/src/BulletCollision/CollisionShapes/btBvhTriangleMeshShape.cpp b/src/BulletCollision/CollisionShapes/btBvhTriangleMeshShape.cpp
index 5cf50931c..819f6f7f9 100644
--- a/src/BulletCollision/CollisionShapes/btBvhTriangleMeshShape.cpp
+++ b/src/BulletCollision/CollisionShapes/btBvhTriangleMeshShape.cpp
@@ -30,7 +30,14 @@ m_ownsBvh(false)
 #ifndef DISABLE_BVH
 
 	btVector3 bvhAabbMin,bvhAabbMax;
-	meshInterface->calculateAabbBruteForce(bvhAabbMin,bvhAabbMax);
+	if(meshInterface->hasPremadeAabb())
+	{
+		meshInterface->getPremadeAabb(&bvhAabbMin, &bvhAabbMax);
+	}
+	else
+	{
+		meshInterface->calculateAabbBruteForce(bvhAabbMin,bvhAabbMax);
+	}
 	
 	if (buildBvh)
 	{
diff --git a/src/BulletCollision/CollisionShapes/btStridingMeshInterface.h b/src/BulletCollision/CollisionShapes/btStridingMeshInterface.h
index 345e774fb..85020dd3f 100644
--- a/src/BulletCollision/CollisionShapes/btStridingMeshInterface.h
+++ b/src/BulletCollision/CollisionShapes/btStridingMeshInterface.h
@@ -76,6 +76,10 @@ class  btStridingMeshInterface
 		virtual void	preallocateVertices(int numverts)=0;
 		virtual void	preallocateIndices(int numindices)=0;
 
+		virtual bool	hasPremadeAabb() const { return false; }
+		virtual void	setPremadeAabb(const btVector3& aabbMin, const btVector3& aabbMax ) const {}
+		virtual void	getPremadeAabb(btVector3* aabbMin, btVector3* aabbMax ) const {}
+
 		const btVector3&	getScaling() const {
 			return m_scaling;
 		}
diff --git a/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.cpp b/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.cpp
index f4f938161..8d634a671 100644
--- a/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.cpp
+++ b/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.cpp
@@ -76,3 +76,21 @@ void	btTriangleIndexVertexArray::getLockedReadOnlyVertexIndexBase(const unsigned
 	indicestype = mesh.m_indexType;
 }
 
+bool	btTriangleIndexVertexArray::hasPremadeAabb() const
+{
+	return (m_hasAabb == 1);
+}
+
+void	btTriangleIndexVertexArray::setPremadeAabb(const btVector3& aabbMin, const btVector3& aabbMax )
+{
+	m_aabbMin = aabbMin;
+	m_aabbMax = aabbMax;
+	m_hasAabb = 1; // this is intentionally an int see notes in header
+}
+
+void	btTriangleIndexVertexArray::getPremadeAabb(btVector3* aabbMin, btVector3* aabbMax ) const
+{
+	*aabbMin = m_aabbMin;
+	*aabbMax = m_aabbMax;
+}
+
diff --git a/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.h b/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.h
index a1551460c..e546675f8 100644
--- a/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.h
+++ b/src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.h
@@ -51,14 +51,16 @@ ATTRIBUTE_ALIGNED16( class) btTriangleIndexVertexArray : public btStridingMeshIn
 {
 protected:
 	IndexedMeshArray	m_indexedMeshes;
-	int m_pad[3];
+	int m_pad[2];
+	int m_hasAabb; // using int instead of bool to maintain alignment
+	btVector3 m_aabbMin;
+	btVector3 m_aabbMax;
 
-		
 public:
 
 	BT_DECLARE_ALIGNED_ALLOCATOR();
 
-	btTriangleIndexVertexArray()
+	btTriangleIndexVertexArray() : m_hasAabb(0)
 	{
 	}
 
@@ -103,6 +105,10 @@ public:
 	virtual void	preallocateVertices(int numverts){(void) numverts;}
 	virtual void	preallocateIndices(int numindices){(void) numindices;}
 
+	virtual bool	hasPremadeAabb() const;
+	virtual void	setPremadeAabb(const btVector3& aabbMin, const btVector3& aabbMax );
+	virtual void	getPremadeAabb(btVector3* aabbMin, btVector3* aabbMax ) const;
+
 }
 ;
 
diff --git a/src/BulletCollision/CollisionShapes/btTriangleMeshShape.cpp b/src/BulletCollision/CollisionShapes/btTriangleMeshShape.cpp
index 0d390c88b..cd0a00bbd 100644
--- a/src/BulletCollision/CollisionShapes/btTriangleMeshShape.cpp
+++ b/src/BulletCollision/CollisionShapes/btTriangleMeshShape.cpp
@@ -24,7 +24,14 @@ subject to the following restrictions:
 btTriangleMeshShape::btTriangleMeshShape(btStridingMeshInterface* meshInterface)
 : m_meshInterface(meshInterface)
 {
-	recalcLocalAabb();
+	if(meshInterface->hasPremadeAabb())
+	{
+		meshInterface->getPremadeAabb(&m_localAabbMin, &m_localAabbMax);
+	}
+	else
+	{
+		recalcLocalAabb();
+	}
 }