ode/inc/collision_util.h
author Pat Downey <patd@symbian.org>
Tue, 13 Jul 2010 11:29:56 +0100
branchRCL_3
changeset 42 6b0a8425dd42
parent 0 2f259fa3e83a
permissions -rw-r--r--
Merge workaround for bug 2012. Ignore workaround for bug 2584 as no longer appears applicable.

/*************************************************************************
 *                                                                       *
 * Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith.       *
 * All rights reserved.  Email: russ@q12.org   Web: www.q12.org          *
 *                                                                       *
 * This library is free software; you can redistribute it and/or         *
 * modify it under the terms of EITHER:                                  *
 *   (1) The GNU Lesser General Public License as published by the Free  *
 *       Software Foundation; either version 2.1 of the License, or (at  *
 *       your option) any later version. The text of the GNU Lesser      *
 *       General Public License is included with this library in the     *
 *       file LICENSE.TXT.                                               *
 *   (2) The BSD-style license that is included with this library in     *
 *       the file LICENSE-BSD.TXT.                                       *
 *                                                                       *
 * This library is distributed in the hope that it will be useful,       *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *
 * LICENSE.TXT and LICENSE-BSD.TXT for more details.                     *
 *                                                                       *
 *************************************************************************/

/*

some useful collision utility stuff.

*/

#ifndef _ODE_COLLISION_UTIL_H_
#define _ODE_COLLISION_UTIL_H_

#include <ode/common.h>
#include <ode/contact.h>
#include <ode/odemath.h>
#include <ode/rotation.h>


// given a pointer `p' to a dContactGeom, return the dContactGeom at
// p + skip bytes.
#define CONTACT(p,skip) ((dContactGeom*) (((char*)p) + (skip)))


// if the spheres (p1,r1) and (p2,r2) collide, set the contact `c' and
// return 1, else return 0.

int dCollideSpheres (dVector3 p1, dReal r1,
		     dVector3 p2, dReal r2, dContactGeom *c);


// given two lines
//    qa = pa + alpha* ua
//    qb = pb + beta * ub
// where pa,pb are two points, ua,ub are two unit length vectors, and alpha,
// beta go from [-inf,inf], return alpha and beta such that qa and qb are
// as close as possible

void dLineClosestApproach (const dVector3 pa, const dVector3 ua,
			   const dVector3 pb, const dVector3 ub,
			   dReal *alpha, dReal *beta);


// given a line segment p1-p2 and a box (center 'c', rotation 'R', side length
// vector 'side'), compute the points of closest approach between the box
// and the line. return these points in 'lret' (the point on the line) and
// 'bret' (the point on the box). if the line actually penetrates the box
// then the solution is not unique, but only one solution will be returned.
// in this case the solution points will coincide.

void dClosestLineBoxPoints (const dVector3 p1, const dVector3 p2,
			    const dVector3 c, const dMatrix3 R,
			    const dVector3 side,
			    dVector3 lret, dVector3 bret);

// 20 Apr 2004
// Start code by Nguyen Binh
int dClipEdgeToPlane(dVector3 &vEpnt0, dVector3 &vEpnt1, const dVector4& plPlane);
// clip polygon with plane and generate new polygon points
void dClipPolyToPlane(const dVector3 avArrayIn[], const int ctIn, dVector3 avArrayOut[], int &ctOut, const dVector4 &plPlane );

void dClipPolyToCircle(const dVector3 avArrayIn[], const int ctIn, dVector3 avArrayOut[], int &ctOut, const dVector4 &plPlane ,dReal fRadius);

// Some vector math
inline void dVector3Subtract(const dVector3& a,const dVector3& b,dVector3& c)
{
	c[0] = a[0] - b[0];
	c[1] = a[1] - b[1];
	c[2] = a[2] - b[2];
}

// Some vector math
inline void dVector3Scale(dVector3& a,dReal nScale)
{
	a[0] = dMUL(a[0],nScale);
	a[1] = dMUL(a[1],nScale);
	a[2] = dMUL(a[2],nScale);
}

inline void dVector3Add(const dVector3& a,const dVector3& b,dVector3& c)
{
	c[0] = a[0] + b[0];
	c[1] = a[1] + b[1];
	c[2] = a[2] + b[2];
}

inline void dVector3Copy(const dVector3& a,dVector3& c)
{
	c[0] = a[0];
	c[1] = a[1];
	c[2] = a[2];
}

inline void dVector3Cross(const dVector3& a,const dVector3& b,dVector3& c)
{
	dCROSS(c,=,a,b);
}

inline dReal dVector3Length(const dVector3& a)
{
	return dSqrt(dMUL(a[0],a[0])+dMUL(a[1],a[1])+dMUL(a[2],a[2]));
}

inline dReal dVector3Dot(const dVector3& a,const dVector3& b)
{
	return dDOT(a,b);
}

inline void dVector3Inv(dVector3& a)
{
	a[0] = -a[0];
	a[1] = -a[1];
	a[2] = -a[2];
}

inline dReal dVector3Length2(const dVector3& a)
{
	return (dMUL(a[0],a[0])+dMUL(a[1],a[1])+dMUL(a[2],a[2]));
}

inline void dMat3GetCol(const dMatrix3& m,const int col, dVector3& v)
{
	v[0] = m[col + 0];
	v[1] = m[col + 4];
	v[2] = m[col + 8];
}

inline void dVector3CrossMat3Col(const dMatrix3& m,const int col,const dVector3& v,dVector3& r)
{
	r[0] =  dMUL(v[1],m[2*4 + col]) - dMUL(v[2],m[1*4 + col]); 
	r[1] =  dMUL(v[2],m[0*4 + col]) - dMUL(v[0],m[2*4 + col]); 
	r[2] =  dMUL(v[0],m[1*4 + col]) - dMUL(v[1],m[0*4 + col]);
}

inline void dMat3ColCrossVector3(const dMatrix3& m,const int col,const dVector3& v,dVector3& r)
{
	r[0] =   dMUL(v[2],m[1*4 + col]) - dMUL(v[1],m[2*4 + col]); 
	r[1] =   dMUL(v[0],m[2*4 + col]) - dMUL(v[2],m[0*4 + col]); 
	r[2] =   dMUL(v[1],m[0*4 + col]) - dMUL(v[0],m[1*4 + col]);
}

inline void dMultiplyMat3Vec3(const dMatrix3& m,const dVector3& v, dVector3& r)
{
	dMULTIPLY0_331(r,m,v);
}

inline dReal dPointPlaneDistance(const dVector3& point,const dVector4& plane)
{
	return (dMUL(plane[0],point[0]) + dMUL(plane[1],point[1]) + dMUL(plane[2],point[2]) + plane[3]);
}

inline void dConstructPlane(const dVector3& normal,const dReal& distance, dVector4& plane)
{
	plane[0] = normal[0];
	plane[1] = normal[1];
	plane[2] = normal[2];
	plane[3] = distance;
}

inline void dMatrix3Copy(const dReal* source,dMatrix3& dest)
{
	dest[0]	=	source[0];
	dest[1]	=	source[1];
	dest[2]	=	source[2];

	dest[4]	=	source[4];
	dest[5]	=	source[5];
	dest[6]	=	source[6];

	dest[8]	=	source[8];
	dest[9]	=	source[9];
	dest[10]=	source[10];
}

inline dReal dMatrix3Det( const dMatrix3& mat )
{
	dReal det;

	det = dMUL(mat[0],( dMUL(mat[5],mat[10]) - dMUL(mat[9],mat[6]) ))
		- dMUL(mat[1],( dMUL(mat[4],mat[10]) - dMUL(mat[8],mat[6]) ))
		+ dMUL(mat[2],( dMUL(mat[4],mat[9])  - dMUL(mat[8],mat[5]) ));

	return( det );
}


inline void dMatrix3Inv( const dMatrix3& ma, dMatrix3& dst )
{
	dReal det = dMatrix3Det( ma );

	if ( dFabs( det ) < REAL(0.0005) )
	{
		dRSetIdentity( dst );
		return;
	}

	dst[0] =    dMUL(ma[5],ma[10]) - dDIV(dMUL(ma[6],ma[9]),det);
	dst[1] = -dDIV(( dMUL(ma[1],ma[10]) - dMUL(ma[9],ma[2]) ),det);
	dst[2] =    dMUL(ma[1],ma[6])  - dDIV(dMUL(ma[5],ma[2]),det);

	dst[4] = -dDIV(( dMUL(ma[4],ma[10]) - dMUL(ma[6],ma[8]) ),det);
	dst[5] =    dMUL(ma[0],ma[10]) - dDIV(dMUL(ma[8],ma[2]),det);
	dst[6] = -dDIV(( dMUL(ma[0],ma[6]) - dMUL(ma[4],ma[2]) ),det);

	dst[8] =    dMUL(ma[4],ma[9]) - dDIV(dMUL(ma[8],ma[5]),det);
	dst[9] = -dDIV(( dMUL(ma[0],ma[9]) - dMUL(ma[8],ma[1]) ),det);
	dst[10] =    dMUL(ma[0],ma[5]) - dDIV(dMUL(ma[1],ma[4]),det);
}

inline void dQuatTransform(const dQuaternion& quat,const dVector3& source,dVector3& dest)
{

	// Nguyen Binh : this code seem to be the fastest.
	dReal x0 = 	dMUL(source[0],quat[0]) + dMUL(source[2],quat[2]) - dMUL(source[1],quat[3]);
	dReal x1 = 	dMUL(source[1],quat[0]) + dMUL(source[0],quat[3]) - dMUL(source[2],quat[1]);
	dReal x2 = 	dMUL(source[2],quat[0]) + dMUL(source[1],quat[1]) - dMUL(source[0],quat[2]);
	dReal x3 = 	dMUL(source[0],quat[1]) + dMUL(source[1],quat[2]) + dMUL(source[2],quat[3]);

	dest[0]  = 	dMUL(quat[0],x0) + dMUL(quat[1],x3) + dMUL(quat[2],x2) - dMUL(quat[3],x1);
	dest[1]  = 	dMUL(quat[0],x1) + dMUL(quat[2],x3) + dMUL(quat[3],x0) - dMUL(quat[1],x2);
	dest[2]  = 	dMUL(quat[0],x2) + dMUL(quat[3],x3) + dMUL(quat[1],x1) - dMUL(quat[2],x0);

	/*
	// nVidia SDK implementation
	dVector3 uv, uuv; 
	dVector3 qvec;
	qvec[0] = quat[1];
	qvec[1] = quat[2];
	qvec[2] = quat[3];

	dVector3Cross(qvec,source,uv);
	dVector3Cross(qvec,uv,uuv);

	dVector3Scale(uv,REAL(2.0)*quat[0]);
	dVector3Scale(uuv,REAL(2.0));

	dest[0] = source[0] + uv[0] + uuv[0];
	dest[1] = source[1] + uv[1] + uuv[1];
	dest[2] = source[2] + uv[2] + uuv[2];   
	*/
}

inline void dQuatInvTransform(const dQuaternion& quat,const dVector3& source,dVector3& dest)
{

	dReal norm = dMUL(quat[0],quat[0]) + dMUL(quat[1],quat[1]) + dMUL(quat[2],quat[2]) + dMUL(quat[3],quat[3]);

	if (norm > REAL(0.0))
	{
		dQuaternion invQuat;
		invQuat[0] =  dDIV(quat[0],norm);
		invQuat[1] = -dDIV(quat[1],norm);
		invQuat[2] = -dDIV(quat[2],norm);
		invQuat[3] = -dDIV(quat[3],norm);	
		
		dQuatTransform(invQuat,source,dest);

	}
	else
	{
		// Singular -> return identity
		dVector3Copy(source,dest);
	}
}

inline void dGetEulerAngleFromRot(const dMatrix3& mRot,dReal& rX,dReal& rY,dReal& rZ)
{
	rY = asin(mRot[0 * 4 + 2]);
	if (rY < dPI /2)
	{
		if (rY > -dPI /2)
		{
			rX = atan2(-mRot[1*4 + 2], mRot[2*4 + 2]);
			rZ = atan2(-mRot[0*4 + 1], mRot[0*4 + 0]);
		}
		else
		{
			// not unique
			rX = -atan2(mRot[1*4 + 0], mRot[1*4 + 1]);
			rZ = REAL(0.0);
		}
	}
	else
	{
		// not unique
		rX = atan2(mRot[1*4 + 0], mRot[1*4 + 1]);
		rZ = REAL(0.0);
	}
}

inline void dQuatInv(const dQuaternion& source, dQuaternion& dest)
{
	dReal norm = dMUL(source[0],source[0]) + dMUL(source[1],source[1]) + dMUL(source[2],source[2]) + dMUL(source[3],source[3]);

	if (norm > REAL(0.0f))
	{
		dest[0] = dDIV(source[0],norm);
		dest[1] = -dDIV(source[1],norm);
		dest[2] = -dDIV(source[2],norm);
		dest[3] = -dDIV(source[3],norm);	
	}
	else
	{
		// Singular -> return identity
		dest[0] = REAL(1.0);
		dest[1] = REAL(0.0);
		dest[2] = REAL(0.0);
		dest[3] = REAL(0.0);
	}
}

#if 1
// Fetches a contact
inline dContactGeom* SAFECONTACT(int /*Flags*/, dContactGeom* Contacts, int Index, int Stride){

	return ((dContactGeom*)(((char*)Contacts) + (Index * Stride)));
}
#endif


#endif