source: code/trunk/src/external/bullet/BulletDynamics/ConstraintSolver/btSolverConstraint.h @ 12222

/*
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 BT_SOLVER_CONSTRAINT_H
#define BT_SOLVER_CONSTRAINT_H

class   btRigidBody;
#include "LinearMath/btVector3.h"
#include "LinearMath/btMatrix3x3.h"
#include "btJacobianEntry.h"

//#define NO_FRICTION_TANGENTIALS 1
#include "btSolverBody.h"


///1D constraint along a normal axis between bodyA and bodyB. It can be combined to solve contact and friction constraints.
ATTRIBUTE_ALIGNED64 (struct)    btSolverConstraint
{
        BT_DECLARE_ALIGNED_ALLOCATOR();

        btVector3               m_relpos1CrossNormal;
        btVector3               m_contactNormal;

        btVector3               m_relpos2CrossNormal;
        //btVector3             m_contactNormal2;//usually m_contactNormal2 == -m_contactNormal

        btVector3               m_angularComponentA;
        btVector3               m_angularComponentB;
        
        mutable btSimdScalar    m_appliedPushImpulse;
        mutable btSimdScalar    m_appliedImpulse;
        
        
        btScalar        m_friction;
        btScalar        m_jacDiagABInv;
        union
        {
                int     m_numConsecutiveRowsPerKernel;
                btScalar        m_unusedPadding0;
        };

        union
        {
                int                     m_frictionIndex;
                btScalar        m_unusedPadding1;
        };
        union
        {
                btRigidBody*    m_solverBodyA;
                int                             m_companionIdA;
        };
        union
        {
                btRigidBody*    m_solverBodyB;
                int                             m_companionIdB;
        };
        
        union
        {
                void*           m_originalContactPoint;
                btScalar        m_unusedPadding4;
        };

        btScalar                m_rhs;
        btScalar                m_cfm;
        btScalar                m_lowerLimit;
        btScalar                m_upperLimit;

        btScalar                m_rhsPenetration;

        enum            btSolverConstraintType
        {
                BT_SOLVER_CONTACT_1D = 0,
                BT_SOLVER_FRICTION_1D
        };
};

typedef btAlignedObjectArray<btSolverConstraint>        btConstraintArray;


#endif //BT_SOLVER_CONSTRAINT_H