2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org
5 This software is provided 'as-is', without any express or implied warranty.
6 In no event will the authors be held liable for any damages arising from the use of this software.
7 Permission is granted to anyone to use this software for any purpose,
8 including commercial applications, and to alter it and redistribute it freely,
9 subject to the following restrictions:
11 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
12 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
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16 #ifndef BT_COMPOUND_SHAPE_H
17 #define BT_COMPOUND_SHAPE_H
19 #include "btCollisionShape.h"
21 #include "LinearMath/btVector3.h"
22 #include "LinearMath/btTransform.h"
23 #include "LinearMath/btMatrix3x3.h"
24 #include "btCollisionMargin.h"
25 #include "LinearMath/btAlignedObjectArray.h"
27 //class btOptimizedBvh;
30 ATTRIBUTE_ALIGNED16(struct)
33 BT_DECLARE_ALIGNED_ALLOCATOR();
35 btTransform m_transform;
36 btCollisionShape* m_childShape;
38 btScalar m_childMargin;
39 struct btDbvtNode* m_node;
42 SIMD_FORCE_INLINE bool operator==(const btCompoundShapeChild& c1, const btCompoundShapeChild& c2)
44 return (c1.m_transform == c2.m_transform &&
45 c1.m_childShape == c2.m_childShape &&
46 c1.m_childShapeType == c2.m_childShapeType &&
47 c1.m_childMargin == c2.m_childMargin);
50 /// The btCompoundShape allows to store multiple other btCollisionShapes
51 /// This allows for moving concave collision objects. This is more general then the static concave btBvhTriangleMeshShape.
52 /// It has an (optional) dynamic aabb tree to accelerate early rejection tests.
53 /// @todo: This aabb tree can also be use to speed up ray tests on btCompoundShape, see http://code.google.com/p/bullet/issues/detail?id=25
54 /// Currently, removal of child shapes is only supported when disabling the aabb tree (pass 'false' in the constructor of btCompoundShape)
55 ATTRIBUTE_ALIGNED16(class)
56 btCompoundShape : public btCollisionShape
59 btAlignedObjectArray<btCompoundShapeChild> m_children;
60 btVector3 m_localAabbMin;
61 btVector3 m_localAabbMax;
63 btDbvt* m_dynamicAabbTree;
65 ///increment m_updateRevision when adding/removing/replacing child shapes, so that some caches can be updated
68 btScalar m_collisionMargin;
70 btVector3 m_localScaling;
73 BT_DECLARE_ALIGNED_ALLOCATOR();
75 explicit btCompoundShape(bool enableDynamicAabbTree = true, const int initialChildCapacity = 0);
77 virtual ~btCompoundShape();
79 void addChildShape(const btTransform& localTransform, btCollisionShape* shape);
81 /// Remove all children shapes that contain the specified shape
82 virtual void removeChildShape(btCollisionShape * shape);
84 void removeChildShapeByIndex(int childShapeindex);
86 int getNumChildShapes() const
88 return int(m_children.size());
91 btCollisionShape* getChildShape(int index)
93 return m_children[index].m_childShape;
95 const btCollisionShape* getChildShape(int index) const
97 return m_children[index].m_childShape;
100 btTransform& getChildTransform(int index)
102 return m_children[index].m_transform;
104 const btTransform& getChildTransform(int index) const
106 return m_children[index].m_transform;
109 ///set a new transform for a child, and update internal data structures (local aabb and dynamic tree)
110 void updateChildTransform(int childIndex, const btTransform& newChildTransform, bool shouldRecalculateLocalAabb = true);
112 btCompoundShapeChild* getChildList()
114 return &m_children[0];
117 ///getAabb's default implementation is brute force, expected derived classes to implement a fast dedicated version
118 virtual void getAabb(const btTransform& t, btVector3& aabbMin, btVector3& aabbMax) const;
120 /** Re-calculate the local Aabb. Is called at the end of removeChildShapes.
121 Use this yourself if you modify the children or their transforms. */
122 virtual void recalculateLocalAabb();
124 virtual void setLocalScaling(const btVector3& scaling);
126 virtual const btVector3& getLocalScaling() const
128 return m_localScaling;
131 virtual void calculateLocalInertia(btScalar mass, btVector3 & inertia) const;
133 virtual void setMargin(btScalar margin)
135 m_collisionMargin = margin;
137 virtual btScalar getMargin() const
139 return m_collisionMargin;
141 virtual const char* getName() const
146 const btDbvt* getDynamicAabbTree() const
148 return m_dynamicAabbTree;
151 btDbvt* getDynamicAabbTree()
153 return m_dynamicAabbTree;
156 void createAabbTreeFromChildren();
158 ///computes the exact moment of inertia and the transform from the coordinate system defined by the principal axes of the moment of inertia
159 ///and the center of mass to the current coordinate system. "masses" points to an array of masses of the children. The resulting transform
160 ///"principal" has to be applied inversely to all children transforms in order for the local coordinate system of the compound
161 ///shape to be centered at the center of mass and to coincide with the principal axes. This also necessitates a correction of the world transform
162 ///of the collision object by the principal transform.
163 void calculatePrincipalAxisTransform(const btScalar* masses, btTransform& principal, btVector3& inertia) const;
165 int getUpdateRevision() const
167 return m_updateRevision;
170 virtual int calculateSerializeBufferSize() const;
172 ///fills the dataBuffer and returns the struct name (and 0 on failure)
173 virtual const char* serialize(void* dataBuffer, btSerializer* serializer) const;
178 ///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
179 struct btCompoundShapeChildData
181 btTransformFloatData m_transform;
182 btCollisionShapeData *m_childShape;
183 int m_childShapeType;
187 ///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
188 struct btCompoundShapeData
190 btCollisionShapeData m_collisionShapeData;
192 btCompoundShapeChildData *m_childShapePtr;
194 int m_numChildShapes;
196 float m_collisionMargin;
202 SIMD_FORCE_INLINE int btCompoundShape::calculateSerializeBufferSize() const
204 return sizeof(btCompoundShapeData);
207 #endif //BT_COMPOUND_SHAPE_H