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Diffstat (limited to 'thirdparty/bullet/src/BulletCollision/CollisionShapes/btHeightfieldTerrainShape.h')
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diff --git a/thirdparty/bullet/src/BulletCollision/CollisionShapes/btHeightfieldTerrainShape.h b/thirdparty/bullet/src/BulletCollision/CollisionShapes/btHeightfieldTerrainShape.h new file mode 100644 index 0000000000..4a7a4a4bda --- /dev/null +++ b/thirdparty/bullet/src/BulletCollision/CollisionShapes/btHeightfieldTerrainShape.h @@ -0,0 +1,167 @@ +/* +Bullet Continuous Collision Detection and Physics Library +Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org + +This software is provided 'as-is', without any express or implied warranty. +In no event will the authors be held liable for any damages arising from the use of this software. +Permission is granted to anyone to use this software for any purpose, +including commercial applications, and to alter it and redistribute it freely, +subject to the following restrictions: + +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. +2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. +3. This notice may not be removed or altered from any source distribution. +*/ + +#ifndef BT_HEIGHTFIELD_TERRAIN_SHAPE_H +#define BT_HEIGHTFIELD_TERRAIN_SHAPE_H + +#include "btConcaveShape.h" + +///btHeightfieldTerrainShape simulates a 2D heightfield terrain +/** + The caller is responsible for maintaining the heightfield array; this + class does not make a copy. + + The heightfield can be dynamic so long as the min/max height values + capture the extremes (heights must always be in that range). + + The local origin of the heightfield is assumed to be the exact + center (as determined by width and length and height, with each + axis multiplied by the localScaling). + + \b NOTE: be careful with coordinates. If you have a heightfield with a local + min height of -100m, and a max height of +500m, you may be tempted to place it + at the origin (0,0) and expect the heights in world coordinates to be + -100 to +500 meters. + Actually, the heights will be -300 to +300m, because bullet will re-center + the heightfield based on its AABB (which is determined by the min/max + heights). So keep in mind that once you create a btHeightfieldTerrainShape + object, the heights will be adjusted relative to the center of the AABB. This + is different to the behavior of many rendering engines, but is useful for + physics engines. + + Most (but not all) rendering and heightfield libraries assume upAxis = 1 + (that is, the y-axis is "up"). This class allows any of the 3 coordinates + to be "up". Make sure your choice of axis is consistent with your rendering + system. + + The heightfield heights are determined from the data type used for the + heightfieldData array. + + - PHY_UCHAR: height at a point is the uchar value at the + grid point, multipled by heightScale. uchar isn't recommended + because of its inability to deal with negative values, and + low resolution (8-bit). + + - PHY_SHORT: height at a point is the short int value at that grid + point, multipled by heightScale. + + - PHY_FLOAT: height at a point is the float value at that grid + point. heightScale is ignored when using the float heightfield + data type. + + Whatever the caller specifies as minHeight and maxHeight will be honored. + The class will not inspect the heightfield to discover the actual minimum + or maximum heights. These values are used to determine the heightfield's + axis-aligned bounding box, multiplied by localScaling. + + For usage and testing see the TerrainDemo. + */ +ATTRIBUTE_ALIGNED16(class) btHeightfieldTerrainShape : public btConcaveShape +{ +protected: + btVector3 m_localAabbMin; + btVector3 m_localAabbMax; + btVector3 m_localOrigin; + + ///terrain data + int m_heightStickWidth; + int m_heightStickLength; + btScalar m_minHeight; + btScalar m_maxHeight; + btScalar m_width; + btScalar m_length; + btScalar m_heightScale; + union + { + const unsigned char* m_heightfieldDataUnsignedChar; + const short* m_heightfieldDataShort; + const btScalar* m_heightfieldDataFloat; + const void* m_heightfieldDataUnknown; + }; + + PHY_ScalarType m_heightDataType; + bool m_flipQuadEdges; + bool m_useDiamondSubdivision; + bool m_useZigzagSubdivision; + + int m_upAxis; + + btVector3 m_localScaling; + + virtual btScalar getRawHeightFieldValue(int x,int y) const; + void quantizeWithClamp(int* out, const btVector3& point,int isMax) const; + void getVertex(int x,int y,btVector3& vertex) const; + + + + /// protected initialization + /** + Handles the work of constructors so that public constructors can be + backwards-compatible without a lot of copy/paste. + */ + void initialize(int heightStickWidth, int heightStickLength, + const void* heightfieldData, btScalar heightScale, + btScalar minHeight, btScalar maxHeight, int upAxis, + PHY_ScalarType heightDataType, bool flipQuadEdges); + +public: + + BT_DECLARE_ALIGNED_ALLOCATOR(); + + /// preferred constructor + /** + This constructor supports a range of heightfield + data types, and allows for a non-zero minimum height value. + heightScale is needed for any integer-based heightfield data types. + */ + btHeightfieldTerrainShape(int heightStickWidth,int heightStickLength, + const void* heightfieldData, btScalar heightScale, + btScalar minHeight, btScalar maxHeight, + int upAxis, PHY_ScalarType heightDataType, + bool flipQuadEdges); + + /// legacy constructor + /** + The legacy constructor assumes the heightfield has a minimum height + of zero. Only unsigned char or floats are supported. For legacy + compatibility reasons, heightScale is calculated as maxHeight / 65535 + (and is only used when useFloatData = false). + */ + btHeightfieldTerrainShape(int heightStickWidth,int heightStickLength,const void* heightfieldData, btScalar maxHeight,int upAxis,bool useFloatData,bool flipQuadEdges); + + virtual ~btHeightfieldTerrainShape(); + + + void setUseDiamondSubdivision(bool useDiamondSubdivision=true) { m_useDiamondSubdivision = useDiamondSubdivision;} + + ///could help compatibility with Ogre heightfields. See https://code.google.com/p/bullet/issues/detail?id=625 + void setUseZigzagSubdivision(bool useZigzagSubdivision=true) { m_useZigzagSubdivision = useZigzagSubdivision;} + + virtual void getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const; + + virtual void processAllTriangles(btTriangleCallback* callback,const btVector3& aabbMin,const btVector3& aabbMax) const; + + virtual void calculateLocalInertia(btScalar mass,btVector3& inertia) const; + + virtual void setLocalScaling(const btVector3& scaling); + + virtual const btVector3& getLocalScaling() const; + + //debugging + virtual const char* getName()const {return "HEIGHTFIELD";} + +}; + +#endif //BT_HEIGHTFIELD_TERRAIN_SHAPE_H |