static void UserContactFriction (const NewtonJoint* contactJoint, dFloat timestep, int threadIndex)
{
dFloat Ixx;
dFloat Iyy;
dFloat Izz;
dFloat mass;
// call the basic call back
GenericContactProcess (contactJoint, timestep, threadIndex);
const NewtonBody* const body0 = NewtonJointGetBody0(contactJoint);
const NewtonBody* const body1 = NewtonJointGetBody1(contactJoint);
const NewtonBody* body = body0;
NewtonBodyGetMass (body, &mass, &Ixx, &Iyy, &Izz);
if (mass == 0.0f) {
body = body1;
}
//now core 300 can have per collision user data
NewtonCollision* const collision = NewtonBodyGetCollision(body);
void* userData = NewtonCollisionGetUserData (collision);
dFloat frictionValue = *((dFloat*)&userData);
for (void* contact = NewtonContactJointGetFirstContact (contactJoint); contact; contact = NewtonContactJointGetNextContact (contactJoint, contact)) {
NewtonMaterial* const material = NewtonContactGetMaterial (contact);
NewtonMaterialSetContactFrictionCoef (material, frictionValue + 0.1f, frictionValue, 0);
NewtonMaterialSetContactFrictionCoef (material, frictionValue + 0.1f, frictionValue, 1);
}
}
void PhysicsWorld::onContactCallback(const NewtonJoint* contactJoint, F32 timestep, int threadIndex)
{
const NewtonBody* body0 = NewtonJointGetBody0(contactJoint);
const NewtonBody* body1 = NewtonJointGetBody1(contactJoint);
F32 friction0 = 0.01;
F32 elasticity0 = 0.001;
F32 friction1 = friction0;
F32 elasticity1 = elasticity0;
void* userData = NewtonBodyGetUserData(body0);
if(userData)
{
friction0 = static_cast<PhysicsBody*>(userData)->getFriction();
elasticity0 = static_cast<PhysicsBody*>(userData)->getElasticity();
}
userData = NewtonBodyGetUserData(body1);
if(userData)
{
friction1 = static_cast<PhysicsBody*>(userData)->getFriction();
elasticity1 = static_cast<PhysicsBody*>(userData)->getElasticity();
}
F32 friction = friction0 + friction1;
F32 elasticity = elasticity0 + elasticity1;
void* contact = NewtonContactJointGetFirstContact(contactJoint);
while(contact)
{
NewtonMaterial* material = NewtonContactGetMaterial(contact);
NewtonMaterialSetContactFrictionCoef(material, friction + 0.1, friction, 0);
NewtonMaterialSetContactFrictionCoef(material, friction + 0.1, friction, 1);
NewtonMaterialSetContactElasticity(material, elasticity);
contact = NewtonContactJointGetNextContact(contactJoint, contact);
}
}
void ApplyTracktionForce (dFloat timestep, const NewtonBody* track)
{
dVector veloc;
dVector omega;
dMatrix matrix;
NewtonBodyGetOmega(m_body0, &omega[0]);
NewtonBodyGetVelocity(m_body0, &veloc[0]);
NewtonBodyGetMatrix (m_body0, &matrix[0][0]);
// itetate over the contact list and condition each contact direction anc contact acclerations
for (NewtonJoint* contactJoint = NewtonBodyGetFirstContactJoint (track); contactJoint; contactJoint = NewtonBodyGetNextContactJoint (track, contactJoint)) {
_ASSERTE ((NewtonJointGetBody0 (contactJoint) == track) || (NewtonJointGetBody1 (contactJoint) == track));
#ifdef REMOVE_REDUNDAT_CONTACT
int contactCount;
contactCount = NewtonContactJointGetContactCount(contactJoint);
if (contactCount > 2) {
// project the contact to the bounday of the conve hull o fteh trhread foot ptint
dFloat maxDist;
dFloat minDist;
void* minContact;
void* maxContact;
dMatrix matrix;
minContact = NULL;
maxContact = NULL;
NewtonBodyGetMatrix (track, &matrix[0][0]);
maxDist = -1.0e10f;
minDist = -1.0e10f;
//find the best two contacts and remove all others
for (void* contact = NewtonContactJointGetFirstContact (contactJoint); contact; contact = NewtonContactJointGetNextContact (contactJoint, contact)) {
dFloat dist;
dVector point;
dVector normal;
NewtonMaterial* material;
material = NewtonContactGetMaterial (contact);
NewtonMaterialGetContactPositionAndNormal(material, &point[0], &normal[0]);
dist = matrix.m_front % point;
if (dist > maxDist) {
maxDist = dist;
maxContact = contact;
}
if (-dist > minDist) {
minDist = -dist;
minContact = contact;
}
}
// now delete all reduntact contacts
void* nextContact;
NewtonWorld* world;
world = NewtonBodyGetWorld (track);
NewtonWorldCriticalSectionLock(world);
for (void* contact = NewtonContactJointGetFirstContact (contactJoint); contact; contact = nextContact) {
nextContact = NewtonContactJointGetNextContact (contactJoint, contact);
if (!((contact == minContact) || (contact == maxContact))) {
NewtonContactJointRemoveContact (contactJoint, contact);
}
}
NewtonWorldCriticalSectionUnlock(world);
}
#endif
for (void* contact = NewtonContactJointGetFirstContact (contactJoint); contact; contact = NewtonContactJointGetNextContact (contactJoint, contact)) {
dFloat speed;
dFloat accel;
dVector point;
dVector normal;
dVector dir0;
dVector dir1;
NewtonMaterial* material;
material = NewtonContactGetMaterial (contact);
NewtonMaterialContactRotateTangentDirections (material, &matrix.m_front[0]);
NewtonMaterialGetContactPositionAndNormal(material, &point[0], &normal[0]);
NewtonMaterialGetContactTangentDirections (material, &dir0[0], &dir1[0]);
dVector posit (point - matrix.m_posit);
veloc += omega * posit;
speed = veloc % dir0;
// accel = m_accel - 0.1f * speed + (((posit % m_matrix.m_right) > 0.0f) ? m_turnAccel : - m_turnAccel);
accel = m_veloc + (((posit % matrix.m_right) > 0.0f) ? m_turnVeloc : - m_turnVeloc);
accel = (accel - speed) * 0.5f / timestep;
// NewtonMaterialSetContactStaticFrictionCoef (material, 1.0f, 0);
// NewtonMaterialSetContactKineticFrictionCoef (material, 1.0f, 0);
NewtonMaterialSetContactFrictionCoef (material, 1.0f, 1.0f, 0);
// NewtonMaterialSetContactStaticFrictionCoef (material, 0.5f, 1);
// NewtonMaterialSetContactKineticFrictionCoef (material, 0.5f, 1);
NewtonMaterialSetContactFrictionCoef (material, 0.5f, 0.5f, 1);
NewtonMaterialSetContactTangentAcceleration (material, accel, 0);
}
// for debug purpose show the contact
ShowJointContacts (contactJoint);
}
}
void dNewtonContactMaterial::SetContactFrictionCoef (const void* const contact, dFloat staticFrictionCoef, dFloat kineticFrictionCoef, int index)
{
NewtonMaterial* const material = NewtonContactGetMaterial (contact);
NewtonMaterialSetContactFrictionCoef (material, staticFrictionCoef, kineticFrictionCoef, index);
}
