bullet3/Bullet/CollisionShapes/BoxShape.h

/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/

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 OBB_BOX_MINKOWSKI_H
#define OBB_BOX_MINKOWSKI_H

#include "PolyhedralConvexShape.h"
#include "CollisionShapes/CollisionMargin.h"
#include "BroadphaseCollision/BroadphaseProxy.h"
#include "SimdPoint3.h"
#include "SimdMinMax.h"

///BoxShape implements both a feature based (vertex/edge/plane) and implicit (getSupportingVertex) Box
class BoxShape: public PolyhedralConvexShape
{

	SimdVector3	m_boxHalfExtents1;


public:

	virtual ~BoxShape()
	{

	}

	SimdVector3 GetHalfExtents() const;
	//{ return m_boxHalfExtents1 * m_localScaling;}
 	//const SimdVector3& GetHalfExtents() const{ return m_boxHalfExtents1;}


	
	virtual int	GetShapeType() const { return BOX_SHAPE_PROXYTYPE;}

	virtual SimdVector3	LocalGetSupportingVertex(const SimdVector3& vec) const
	{
		
		SimdVector3 halfExtents = GetHalfExtents();
		
		SimdVector3 supVertex;
		supVertex = SimdPoint3(vec.x() < SimdScalar(0.0f) ? -halfExtents.x() : halfExtents.x(),
                     vec.y() < SimdScalar(0.0f) ? -halfExtents.y() : halfExtents.y(),
                     vec.z() < SimdScalar(0.0f) ? -halfExtents.z() : halfExtents.z()); 
  
		return supVertex;
	}

	virtual inline SimdVector3	LocalGetSupportingVertexWithoutMargin(const SimdVector3& vec)const
	{
		SimdVector3 halfExtents = GetHalfExtents();
		SimdVector3 margin(GetMargin(),GetMargin(),GetMargin());
		halfExtents -= margin;

		return SimdVector3(vec.x() < SimdScalar(0.0f) ? -halfExtents.x() : halfExtents.x(),
                    vec.y() < SimdScalar(0.0f) ? -halfExtents.y() : halfExtents.y(),
                    vec.z() < SimdScalar(0.0f) ? -halfExtents.z() : halfExtents.z()); 
	}

	virtual void	BatchedUnitVectorGetSupportingVertexWithoutMargin(const SimdVector3* vectors,SimdVector3* supportVerticesOut,int numVectors) const
	{
		SimdVector3 halfExtents = GetHalfExtents();
		SimdVector3 margin(GetMargin(),GetMargin(),GetMargin());
		halfExtents -= margin;


		for (int i=0;i<numVectors;i++)
		{
			const SimdVector3& vec = vectors[i];
			supportVerticesOut[i].setValue(vec.x() < SimdScalar(0.0f) ? -halfExtents.x() : halfExtents.x(),
                    vec.y() < SimdScalar(0.0f) ? -halfExtents.y() : halfExtents.y(),
                    vec.z() < SimdScalar(0.0f) ? -halfExtents.z() : halfExtents.z()); 
		}

	}


	BoxShape( const SimdVector3& boxHalfExtents) :  m_boxHalfExtents1(boxHalfExtents){};
	
	virtual void GetAabb(const SimdTransform& t,SimdVector3& aabbMin,SimdVector3& aabbMax) const;

	

	virtual void	CalculateLocalInertia(SimdScalar mass,SimdVector3& inertia);

	virtual void GetPlane(SimdVector3& planeNormal,SimdPoint3& planeSupport,int i ) const
	{
		//this plane might not be aligned...
		SimdVector4 plane ;
		GetPlaneEquation(plane,i);
		planeNormal = SimdVector3(plane.getX(),plane.getY(),plane.getZ());
		planeSupport = LocalGetSupportingVertex(-planeNormal);
	}

	
	virtual int GetNumPlanes() const
	{
		return 6;
	}	
	
	virtual int	GetNumVertices() const 
	{
		return 8;
	}

	virtual int GetNumEdges() const
	{
		return 12;
	}


	virtual void GetVertex(int i,SimdVector3& vtx) const
	{
		SimdVector3 halfExtents = GetHalfExtents();

		vtx = SimdVector3(
				halfExtents.x() * (1-(i&1)) - halfExtents.x() * (i&1),
				halfExtents.y() * (1-((i&2)>>1)) - halfExtents.y() * ((i&2)>>1),
				halfExtents.z() * (1-((i&4)>>2)) - halfExtents.z() * ((i&4)>>2));
	}
	

	virtual void	GetPlaneEquation(SimdVector4& plane,int i) const
	{
		SimdVector3 halfExtents = GetHalfExtents();

		switch (i)
		{
		case 0:
			plane.setValue(1.f,0.f,0.f);
			plane[3] = -halfExtents.x();
			break;
		case 1:
			plane.setValue(-1.f,0.f,0.f);
			plane[3] = -halfExtents.x();
			break;
		case 2:
			plane.setValue(0.f,1.f,0.f);
			plane[3] = -halfExtents.y();
			break;
		case 3:
			plane.setValue(0.f,-1.f,0.f);
			plane[3] = -halfExtents.y();
			break;
		case 4:
			plane.setValue(0.f,0.f,1.f);
			plane[3] = -halfExtents.z();
			break;
		case 5:
			plane.setValue(0.f,0.f,-1.f);
			plane[3] = -halfExtents.z();
			break;
		default:
			assert(0);
		}
	}

	
	virtual void GetEdge(int i,SimdPoint3& pa,SimdPoint3& pb) const
	//virtual void GetEdge(int i,Edge& edge) const
	{
		int edgeVert0 = 0;
		int edgeVert1 = 0;

		switch (i)
		{
		case 0:
				edgeVert0 = 0;
				edgeVert1 = 1;
			break;
		case 1:
				edgeVert0 = 0;
				edgeVert1 = 2;
			break;
		case 2:
			edgeVert0 = 1;
			edgeVert1 = 3;

			break;
		case 3:
			edgeVert0 = 2;
			edgeVert1 = 3;
			break;
		case 4:
			edgeVert0 = 0;
			edgeVert1 = 4;
			break;
		case 5:
			edgeVert0 = 1;
			edgeVert1 = 5;

			break;
		case 6:
			edgeVert0 = 2;
			edgeVert1 = 6;
			break;
		case 7:
			edgeVert0 = 3;
			edgeVert1 = 7;
			break;
		case 8:
			edgeVert0 = 4;
			edgeVert1 = 5;
			break;
		case 9:
			edgeVert0 = 4;
			edgeVert1 = 6;
			break;
		case 10:
			edgeVert0 = 5;
			edgeVert1 = 7;
			break;
		case 11:
			edgeVert0 = 6;
			edgeVert1 = 7;
			break;
		default:
			ASSERT(0);

		}

		GetVertex(edgeVert0,pa );
		GetVertex(edgeVert1,pb );
	}




	
	virtual	bool IsInside(const SimdPoint3& pt,SimdScalar tolerance) const
	{
		SimdVector3 halfExtents = GetHalfExtents();

		//SimdScalar minDist = 2*tolerance;
		
		bool result =	(pt.x() <= (halfExtents.x()+tolerance)) &&
						(pt.x() >= (-halfExtents.x()-tolerance)) &&
						(pt.y() <= (halfExtents.y()+tolerance)) &&
						(pt.y() >= (-halfExtents.y()-tolerance)) &&
						(pt.z() <= (halfExtents.z()+tolerance)) &&
						(pt.z() >= (-halfExtents.z()-tolerance));
		
		return result;
	}


	//debugging
	virtual char*	GetName()const
	{
		return "Box";
	}


};

#endif //OBB_BOX_MINKOWSKI_H