reactphysics3d/src/collision/shapes/HeightFieldShape.h

293 lines
11 KiB
C++

/********************************************************************************
* ReactPhysics3D physics library, http://www.reactphysics3d.com *
* Copyright (c) 2010-2018 Daniel Chappuis *
*********************************************************************************
* *
* 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 REACTPHYSICS3D_HEIGHTFIELD_SHAPE_H
#define REACTPHYSICS3D_HEIGHTFIELD_SHAPE_H
// Libraries
#include "ConcaveShape.h"
#include "collision/shapes/AABB.h"
namespace reactphysics3d {
class HeightFieldShape;
class Profiler;
class TriangleShape;
// Class TriangleOverlapCallback
/**
* This class is used for testing AABB and triangle overlap for raycasting
*/
class TriangleOverlapCallback : public TriangleCallback {
protected:
const Ray& mRay;
ProxyShape* mProxyShape;
RaycastInfo& mRaycastInfo;
bool mIsHit;
decimal mSmallestHitFraction;
const HeightFieldShape& mHeightFieldShape;
MemoryAllocator& mAllocator;
#ifdef IS_PROFILING_ACTIVE
/// Pointer to the profiler
Profiler* mProfiler;
#endif
public:
// Constructor
TriangleOverlapCallback(const Ray& ray, ProxyShape* proxyShape, RaycastInfo& raycastInfo,
const HeightFieldShape& heightFieldShape, MemoryAllocator& allocator)
: mRay(ray), mProxyShape(proxyShape), mRaycastInfo(raycastInfo),
mHeightFieldShape (heightFieldShape), mAllocator(allocator) {
mIsHit = false;
mSmallestHitFraction = mRay.maxFraction;
}
bool getIsHit() const {return mIsHit;}
/// Raycast test between a ray and a triangle of the heightfield
virtual void testTriangle(const Vector3* trianglePoints, const Vector3* verticesNormals, uint shapeId) override;
#ifdef IS_PROFILING_ACTIVE
/// Set the profiler
void setProfiler(Profiler* profiler) {
mProfiler = profiler;
}
#endif
};
// Class HeightFieldShape
/**
* This class represents a static height field that can be used to represent
* a terrain. The height field is made of a grid with rows and columns with a
* height value at each grid point. Note that the height values are not copied into the shape
* but are shared instead. The height values can be of type integer, float or double.
* When creating a HeightFieldShape, you need to specify the minimum and maximum height value of
* your height field. Note that the HeightFieldShape will be re-centered based on its AABB. It means
* that for instance, if the minimum height value is -200 and the maximum value is 400, the final
* minimum height of the field in the simulation will be -300 and the maximum height will be 300.
*/
class HeightFieldShape : public ConcaveShape {
public:
/// Data type for the height data of the height field
enum class HeightDataType {HEIGHT_FLOAT_TYPE, HEIGHT_DOUBLE_TYPE, HEIGHT_INT_TYPE};
protected:
// -------------------- Attributes -------------------- //
/// Number of columns in the grid of the height field
int mNbColumns;
/// Number of rows in the grid of the height field
int mNbRows;
/// Height field width
decimal mWidth;
/// Height field length
decimal mLength;
/// Minimum height of the height field
decimal mMinHeight;
/// Maximum height of the height field
decimal mMaxHeight;
/// Up axis direction (0 => x, 1 => y, 2 => z)
int mUpAxis;
/// Height values scale for height field with integer height values
decimal mIntegerHeightScale;
/// Data type of the height values
HeightDataType mHeightDataType;
/// Array of data with all the height values of the height field
const void* mHeightFieldData;
/// Local AABB of the height field (without scaling)
AABB mAABB;
/// Scaling vector
const Vector3 mScaling;
// -------------------- Methods -------------------- //
/// Raycast method with feedback information
virtual bool raycast(const Ray& ray, RaycastInfo& raycastInfo, ProxyShape* proxyShape, MemoryAllocator& allocator) const override;
/// Return the number of bytes used by the collision shape
virtual size_t getSizeInBytes() const override;
/// Insert all the triangles into the dynamic AABB tree
void initBVHTree();
/// Return the three vertices coordinates (in the array outTriangleVertices) of a triangle
/// given the start vertex index pointer of the triangle.
void getTriangleVerticesWithIndexPointer(int32 subPart, int32 triangleIndex,
Vector3* outTriangleVertices) const;
/// Return the closest inside integer grid value of a given floating grid value
int computeIntegerGridValue(decimal value) const;
/// Compute the min/max grid coords corresponding to the intersection of the AABB of the height field and the AABB to collide
void computeMinMaxGridCoordinates(int* minCoords, int* maxCoords, const AABB& aabbToCollide) const;
/// Compute the shape Id for a given triangle
uint computeTriangleShapeId(uint iIndex, uint jIndex, uint secondTriangleIncrement) const;
public:
/// Constructor
HeightFieldShape(int nbGridColumns, int nbGridRows, decimal minHeight, decimal maxHeight,
const void* heightFieldData, HeightDataType dataType,
int upAxis = 1, decimal integerHeightScale = 1.0f,
const Vector3& scaling = Vector3(1,1,1));
/// Destructor
virtual ~HeightFieldShape() override = default;
/// Deleted copy-constructor
HeightFieldShape(const HeightFieldShape& shape) = delete;
/// Deleted assignment operator
HeightFieldShape& operator=(const HeightFieldShape& shape) = delete;
/// Return the scaling factor
const Vector3& getScaling() const;
/// Return the number of rows in the height field
int getNbRows() const;
/// Return the number of columns in the height field
int getNbColumns() const;
/// Return the vertex (local-coordinates) of the height field at a given (x,y) position
Vector3 getVertexAt(int x, int y) const;
/// Return the height of a given (x,y) point in the height field
decimal getHeightAt(int x, int y) const;
/// Return the type of height value in the height field
HeightDataType getHeightDataType() const;
/// Return the local bounds of the shape in x, y and z directions.
virtual void getLocalBounds(Vector3& min, Vector3& max) const override;
/// Return the local inertia tensor of the collision shape
virtual void computeLocalInertiaTensor(Matrix3x3& tensor, decimal mass) const override;
/// Use a callback method on all triangles of the concave shape inside a given AABB
virtual void testAllTriangles(TriangleCallback& callback, const AABB& localAABB) const override;
/// Return the string representation of the shape
virtual std::string to_string() const override;
// ---------- Friendship ----------- //
friend class ConvexTriangleAABBOverlapCallback;
friend class ConcaveMeshRaycastCallback;
};
// Return the scaling factor
inline const Vector3& HeightFieldShape::getScaling() const {
return mScaling;
}
// Return the number of rows in the height field
inline int HeightFieldShape::getNbRows() const {
return mNbRows;
}
// Return the number of columns in the height field
inline int HeightFieldShape::getNbColumns() const {
return mNbColumns;
}
// Return the type of height value in the height field
inline HeightFieldShape::HeightDataType HeightFieldShape::getHeightDataType() const {
return mHeightDataType;
}
// Return the number of bytes used by the collision shape
inline size_t HeightFieldShape::getSizeInBytes() const {
return sizeof(HeightFieldShape);
}
// Return the height of a given (x,y) point in the height field
inline decimal HeightFieldShape::getHeightAt(int x, int y) const {
switch(mHeightDataType) {
case HeightDataType::HEIGHT_FLOAT_TYPE : return ((float*)mHeightFieldData)[y * mNbColumns + x];
case HeightDataType::HEIGHT_DOUBLE_TYPE : return ((double*)mHeightFieldData)[y * mNbColumns + x];
case HeightDataType::HEIGHT_INT_TYPE : return ((int*)mHeightFieldData)[y * mNbColumns + x] * mIntegerHeightScale;
default: assert(false); return 0;
}
}
// Return the closest inside integer grid value of a given floating grid value
inline int HeightFieldShape::computeIntegerGridValue(decimal value) const {
return (value < decimal(0.0)) ? value - decimal(0.5) : value + decimal(0.5);
}
// Return the local inertia tensor
/**
* @param[out] tensor The 3x3 inertia tensor matrix of the shape in local-space
* coordinates
* @param mass Mass to use to compute the inertia tensor of the collision shape
*/
inline void HeightFieldShape::computeLocalInertiaTensor(Matrix3x3& tensor, decimal mass) const {
// Default inertia tensor
// Note that this is not very realistic for a concave triangle mesh.
// However, in most cases, it will only be used static bodies and therefore,
// the inertia tensor is not used.
tensor.setAllValues(mass, 0, 0,
0, mass, 0,
0, 0, mass);
}
// Compute the shape Id for a given triangle
inline uint HeightFieldShape::computeTriangleShapeId(uint iIndex, uint jIndex, uint secondTriangleIncrement) const {
return (jIndex * (mNbColumns - 1) + iIndex) * 2 + secondTriangleIncrement;
}
}
#endif