1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2009 Erwin Coumans  http://bulletphysics.org
4 
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:
10 
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.
13 3. This notice may not be removed or altered from any source distribution.
14 */
15 
16 #ifndef BT_STRIDING_MESHINTERFACE_H
17 #define BT_STRIDING_MESHINTERFACE_H
18 
19 #include "LinearMath/btVector3.h"
20 #include "btTriangleCallback.h"
21 #include "btConcaveShape.h"
22 
23 ///	The btStridingMeshInterface is the interface class for high performance generic access to triangle meshes, used in combination with btBvhTriangleMeshShape and some other collision shapes.
24 /// Using index striding of 3*sizeof(integer) it can use triangle arrays, using index striding of 1*sizeof(integer) it can handle triangle strips.
25 /// It allows for sharing graphics and collision meshes. Also it provides locking/unlocking of graphics meshes that are in gpu memory.
ATTRIBUTE_ALIGNED16(class)26 ATTRIBUTE_ALIGNED16(class)
27 btStridingMeshInterface
28 {
29 protected:
30 	btVector3 m_scaling;
31 
32 public:
33 	BT_DECLARE_ALIGNED_ALLOCATOR();
34 
35 	btStridingMeshInterface() : m_scaling(btScalar(1.), btScalar(1.), btScalar(1.))
36 	{
37 	}
38 
39 	virtual ~btStridingMeshInterface();
40 
41 	virtual void InternalProcessAllTriangles(btInternalTriangleIndexCallback * callback, const btVector3& aabbMin, const btVector3& aabbMax) const;
42 
43 	///brute force method to calculate aabb
44 	void calculateAabbBruteForce(btVector3 & aabbMin, btVector3 & aabbMax);
45 
46 	/// get read and write access to a subpart of a triangle mesh
47 	/// this subpart has a continuous array of vertices and indices
48 	/// in this way the mesh can be handled as chunks of memory with striding
49 	/// very similar to OpenGL vertexarray support
50 	/// make a call to unLockVertexBase when the read and write access is finished
51 	virtual void getLockedVertexIndexBase(unsigned char** vertexbase, int& numverts, PHY_ScalarType& type, int& stride, unsigned char** indexbase, int& indexstride, int& numfaces, PHY_ScalarType& indicestype, int subpart = 0) = 0;
52 
53 	virtual void getLockedReadOnlyVertexIndexBase(const unsigned char** vertexbase, int& numverts, PHY_ScalarType& type, int& stride, const unsigned char** indexbase, int& indexstride, int& numfaces, PHY_ScalarType& indicestype, int subpart = 0) const = 0;
54 
55 	/// unLockVertexBase finishes the access to a subpart of the triangle mesh
56 	/// make a call to unLockVertexBase when the read and write access (using getLockedVertexIndexBase) is finished
57 	virtual void unLockVertexBase(int subpart) = 0;
58 
59 	virtual void unLockReadOnlyVertexBase(int subpart) const = 0;
60 
61 	/// getNumSubParts returns the number of separate subparts
62 	/// each subpart has a continuous array of vertices and indices
63 	virtual int getNumSubParts() const = 0;
64 
65 	virtual void preallocateVertices(int numverts) = 0;
66 	virtual void preallocateIndices(int numindices) = 0;
67 
68 	virtual bool hasPremadeAabb() const { return false; }
69 	virtual void setPremadeAabb(const btVector3& aabbMin, const btVector3& aabbMax) const
70 	{
71 		(void)aabbMin;
72 		(void)aabbMax;
73 	}
74 	virtual void getPremadeAabb(btVector3 * aabbMin, btVector3 * aabbMax) const
75 	{
76 		(void)aabbMin;
77 		(void)aabbMax;
78 	}
79 
80 	const btVector3& getScaling() const
81 	{
82 		return m_scaling;
83 	}
84 	void setScaling(const btVector3& scaling)
85 	{
86 		m_scaling = scaling;
87 	}
88 
89 	virtual int calculateSerializeBufferSize() const;
90 
91 	///fills the dataBuffer and returns the struct name (and 0 on failure)
92 	virtual const char* serialize(void* dataBuffer, btSerializer* serializer) const;
93 };
94 
95 struct btIntIndexData
96 {
97 	int m_value;
98 };
99 
100 struct btShortIntIndexData
101 {
102 	short m_value;
103 	char m_pad[2];
104 };
105 
106 struct btShortIntIndexTripletData
107 {
108 	short m_values[3];
109 	char m_pad[2];
110 };
111 
112 struct btCharIndexTripletData
113 {
114 	unsigned char m_values[3];
115 	char m_pad;
116 };
117 
118 // clang-format off
119 
120 ///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
121 struct	btMeshPartData
122 {
123 	btVector3FloatData			*m_vertices3f;
124 	btVector3DoubleData			*m_vertices3d;
125 
126 	btIntIndexData				*m_indices32;
127 	btShortIntIndexTripletData	*m_3indices16;
128 	btCharIndexTripletData		*m_3indices8;
129 
130 	btShortIntIndexData			*m_indices16;//backwards compatibility
131 
132 	int                     m_numTriangles;//length of m_indices = m_numTriangles
133 	int                     m_numVertices;
134 };
135 
136 
137 ///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
138 struct	btStridingMeshInterfaceData
139 {
140 	btMeshPartData	*m_meshPartsPtr;
141 	btVector3FloatData	m_scaling;
142 	int	m_numMeshParts;
143 	char m_padding[4];
144 };
145 
146 // clang-format on
147 
calculateSerializeBufferSize()148 SIMD_FORCE_INLINE int btStridingMeshInterface::calculateSerializeBufferSize() const
149 {
150 	return sizeof(btStridingMeshInterfaceData);
151 }
152 
153 #endif  //BT_STRIDING_MESHINTERFACE_H
154