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Committing height field terrain work from tomva1@yahoo.com

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This commit is contained in:
john.mccutchan
2008-11-06 19:41:31 +00:00
parent 521314b9e7
commit 9b5df088de
18 changed files with 1257 additions and 130 deletions
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91
src/BulletCollision/CollisionShapes/btHeightfieldTerrainShape.h
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@@ -18,28 +18,69 @@ subject to the following restrictions:
#include "btConcaveShape.h"
///The btHeightfieldTerrainShape simulates a 2D heightfield terrain collision shape. You can also use the more general btBvhTriangleMeshShape instead.
///An example implementation of btHeightfieldTerrainShape is provided in Demos/VehicleDemo/VehicleDemo.cpp
///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).
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.
*/
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
{
unsigned char* m_heightfieldDataUnsignedChar;
short* m_heightfieldDataShort;
btScalar* m_heightfieldDataFloat;
void* m_heightfieldDataUnknown;
};
bool m_useFloatData;
PHY_ScalarType m_heightDataType;
bool m_flipQuadEdges;
bool m_useDiamondSubdivision;
@@ -51,17 +92,39 @@ protected:
void quantizeWithClamp(int* out, const btVector3& point,int isMax) const;
void getVertex(int x,int y,btVector3& vertex) const;
inline bool testQuantizedAabbAgainstQuantizedAabb(int* aabbMin1, int* aabbMax1,const int* aabbMin2,const int* aabbMax2) const
{
bool overlap = true;
overlap = (aabbMin1[0] > aabbMax2[0] || aabbMax1[0] < aabbMin2[0]) ? false : overlap;
overlap = (aabbMin1[2] > aabbMax2[2] || aabbMax1[2] < aabbMin2[2]) ? false : overlap;
overlap = (aabbMin1[1] > aabbMax2[1] || aabbMax1[1] < aabbMin2[1]) ? false : overlap;
return overlap;
}
/// 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,
void* heightfieldData, btScalar heightScale,
btScalar minHeight, btScalar maxHeight, int upAxis,
PHY_ScalarType heightDataType, bool flipQuadEdges);
public:
btHeightfieldTerrainShape(int heightStickWidth,int heightStickHeight,void* heightfieldData, btScalar maxHeight,int upAxis,bool useFloatData,bool flipQuadEdges);
/// 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,
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,void* heightfieldData, btScalar maxHeight,int upAxis,bool useFloatData,bool flipQuadEdges);
virtual ~btHeightfieldTerrainShape();