DySolverConstraintsShared.h

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#ifndef DY_SOLVER_CONSTRAINT_SHARED_H
#define DY_SOLVER_CONSTRAINT_SHARED_H
 
#include "foundation/PxPreprocessor.h"
#include "foundation/PxVecMath.h"
 
#include "DySolverBody.h"
#include "DySolverContact.h"
#include "DySolverConstraint1D.h"
#include "DySolverConstraintDesc.h"
#include "foundation/PxUtilities.h"
#include "DyConstraint.h"
#include "foundation/PxAtomic.h"
 
 
namespace physx
{
 
namespace Dy
{
    PX_FORCE_INLINE static FloatV solveDynamicContacts(SolverContactPoint* contacts, const PxU32 nbContactPoints, const Vec3VArg contactNormal,
    const FloatVArg invMassA, const FloatVArg invMassB, const FloatVArg angDom0, const FloatVArg angDom1, Vec3V& linVel0_, Vec3V& angState0_, 
    Vec3V& linVel1_, Vec3V& angState1_, PxF32* PX_RESTRICT forceBuffer)
{
    Vec3V linVel0 = linVel0_;
    Vec3V angState0 = angState0_;
    Vec3V linVel1 = linVel1_;
    Vec3V angState1 = angState1_;
    FloatV accumulatedNormalImpulse = FZero();
 
    const Vec3V delLinVel0 = V3Scale(contactNormal, invMassA);
    const Vec3V delLinVel1 = V3Scale(contactNormal, invMassB);
 
    for(PxU32 i=0;i<nbContactPoints;i++)
    {
        SolverContactPoint& c = contacts[i];
        PxPrefetchLine(&contacts[i], 128);
 
        const Vec3V raXn = Vec3V_From_Vec4V(c.raXn_velMultiplierW);
 
        const Vec3V rbXn = Vec3V_From_Vec4V(c.rbXn_maxImpulseW);
 
        const FloatV appliedForce = FLoad(forceBuffer[i]);
        const FloatV velMultiplier = c.getVelMultiplier();
        const FloatV impulseMultiplier = c.getImpulseMultiplier();
        
        /*const FloatV targetVel = c.getTargetVelocity();
        const FloatV nScaledBias = c.getScaledBias();*/
        const FloatV maxImpulse = c.getMaxImpulse();
 
        //Compute the normal velocity of the constraint.
        const Vec3V v0 = V3MulAdd(linVel0, contactNormal, V3Mul(angState0, raXn));
        const Vec3V v1 = V3MulAdd(linVel1, contactNormal, V3Mul(angState1, rbXn));
        const FloatV normalVel = V3SumElems(V3Sub(v0, v1));
 
        const FloatV biasedErr = c.getBiasedErr();//FScaleAdd(targetVel, velMultiplier, nScaledBias);
 
        //KS - clamp the maximum force
        const FloatV _deltaF = FMax(FNegScaleSub(normalVel, velMultiplier, biasedErr), FNeg(appliedForce));
        const FloatV _newForce = FAdd(FMul(impulseMultiplier, appliedForce), _deltaF);
        const FloatV newForce = FMin(_newForce, maxImpulse);
        const FloatV deltaF = FSub(newForce, appliedForce);
 
        linVel0 = V3ScaleAdd(delLinVel0, deltaF, linVel0);
        linVel1 = V3NegScaleSub(delLinVel1, deltaF, linVel1);
        angState0 = V3ScaleAdd(raXn, FMul(deltaF, angDom0), angState0);
        angState1 = V3NegScaleSub(rbXn, FMul(deltaF, angDom1), angState1);
        
        FStore(newForce, &forceBuffer[i]);
 
        accumulatedNormalImpulse = FAdd(accumulatedNormalImpulse, newForce);
    }
 
    linVel0_ = linVel0;
    angState0_ = angState0;
    linVel1_ = linVel1;
    angState1_ = angState1;
    return accumulatedNormalImpulse;
}
 
PX_FORCE_INLINE static FloatV solveStaticContacts(SolverContactPoint* contacts, const PxU32 nbContactPoints, const Vec3VArg contactNormal,
    const FloatVArg invMassA, const FloatVArg angDom0, Vec3V& linVel0_, Vec3V& angState0_, PxF32* PX_RESTRICT forceBuffer)
{
    Vec3V linVel0 = linVel0_;
    Vec3V angState0 = angState0_;
    FloatV accumulatedNormalImpulse = FZero();
 
    const Vec3V delLinVel0 = V3Scale(contactNormal, invMassA);
 
    for(PxU32 i=0;i<nbContactPoints;i++)
    {
        SolverContactPoint& c = contacts[i];
        PxPrefetchLine(&contacts[i],128);
 
        const Vec3V raXn = Vec3V_From_Vec4V(c.raXn_velMultiplierW);
        
        const FloatV appliedForce = FLoad(forceBuffer[i]);
        const FloatV velMultiplier = c.getVelMultiplier();
        const FloatV impulseMultiplier = c.getImpulseMultiplier();
 
        /*const FloatV targetVel = c.getTargetVelocity();
        const FloatV nScaledBias = c.getScaledBias();*/
        const FloatV maxImpulse = c.getMaxImpulse();
        
        const Vec3V v0 = V3MulAdd(linVel0, contactNormal, V3Mul(angState0, raXn));
        const FloatV normalVel = V3SumElems(v0);
 
 
        const FloatV biasedErr = c.getBiasedErr();//FScaleAdd(targetVel, velMultiplier, nScaledBias);
 
        // still lots to do here: using loop pipelining we can interweave this code with the
        // above - the code here has a lot of stalls that we would thereby eliminate
        const FloatV _deltaF = FMax(FNegScaleSub(normalVel, velMultiplier, biasedErr), FNeg(appliedForce));
        const FloatV _newForce = FAdd(FMul(appliedForce, impulseMultiplier), _deltaF);
        const FloatV newForce = FMin(_newForce, maxImpulse);
        const FloatV deltaF = FSub(newForce, appliedForce);
 
        linVel0 = V3ScaleAdd(delLinVel0, deltaF, linVel0);
        angState0 = V3ScaleAdd(raXn, FMul(deltaF, angDom0), angState0);
 
        FStore(newForce, &forceBuffer[i]);
 
        accumulatedNormalImpulse = FAdd(accumulatedNormalImpulse, newForce);
    }
 
    linVel0_ = linVel0;
    angState0_ = angState0;
    return accumulatedNormalImpulse;
}
 
FloatV solveExtContacts(SolverContactPointExt* contacts, const PxU32 nbContactPoints, const Vec3VArg contactNormal,
    Vec3V& linVel0, Vec3V& angVel0,
    Vec3V& linVel1, Vec3V& angVel1,
    Vec3V& li0, Vec3V& ai0,
    Vec3V& li1, Vec3V& ai1,
    PxF32* PX_RESTRICT appliedForceBuffer);
 
}
 
}
 
#endif