void PhysicsContact::generateContactData()
{
if (_contactInfo == nullptr)
{
return;
}
cpArbiter* arb = static_cast<cpArbiter*>(_contactInfo);
CC_SAFE_DELETE(_preContactData);
_preContactData = _contactData;
_contactData = new (std::nothrow) PhysicsContactData();
_contactData->count = cpArbiterGetCount(arb);
for (int i=0; i<_contactData->count && i<PhysicsContactData::POINT_MAX; ++i)
{
_contactData->points[i] = PhysicsHelper::cpv2point(cpArbiterGetPoint(arb, i));
}
_contactData->normal = _contactData->count > 0 ? PhysicsHelper::cpv2point(cpArbiterGetNormal(arb, 0)) : Vec2::ZERO;
}
int MagneticGripperGrippableCollisionPreSolve(cpArbiter* pt_arb, cpSpace* pt_space, void* p_data) {
/* Get the shapes involved */
CP_ARBITER_GET_SHAPES(pt_arb, ptGripperShape, ptGrippableShape);
/* Get a reference to the gripper data */
SDynamics2DEngineGripperData& sGripperData = *reinterpret_cast<SDynamics2DEngineGripperData*>(ptGripperShape->data);
/* The gripper is locked or unlocked? */
if(sGripperData.GripperEntity.IsUnlocked()) {
/* The gripper is locked. If it was gripping an object,
* release it. Then, process the collision normally */
if(sGripperData.GripperEntity.IsGripping()) {
sGripperData.ClearConstraints();
}
return 1;
}
else if(! sGripperData.GripperEntity.IsGripping()) {
/* The gripper is unlocked and free, create the joints */
/* Prevent gripper from slipping */
pt_arb->e = 0.0f; // No elasticity
pt_arb->u = 1.0f; // Max friction
pt_arb->surface_vr = cpvzero; // No surface velocity
/* Calculate the anchor point on the grippable body
as the centroid of the contact points */
cpVect tGrippableAnchor = cpvzero;
for(SInt32 i = 0; i < pt_arb->numContacts; ++i) {
tGrippableAnchor = cpvadd(tGrippableAnchor, cpArbiterGetPoint(pt_arb, i));
}
tGrippableAnchor = cpvmult(tGrippableAnchor, 1.0f / pt_arb->numContacts);
/* Create a constraint */
sGripperData.GripConstraint = cpSpaceAddConstraint(pt_space,
cpPivotJointNew(
ptGripperShape->body,
ptGrippableShape->body,
tGrippableAnchor));
sGripperData.GripConstraint->biasCoef = 0.95f; // Correct overlap
sGripperData.GripConstraint->maxBias = 0.01f; // Max correction speed
sGripperData.GripperEntity.SetGrippedEntity(*reinterpret_cast<CEmbodiedEntity*>(ptGrippableShape->data));
}
/* Ignore the collision, the objects are gripped already */
return 0;
}
cVect cArbiter::GetPoint( int i ) {
return tovect( cpArbiterGetPoint( mArbiter, i ) );
}
JNIEXPORT jfloat JNICALL Java_com_wiyun_engine_chipmunk_Arbiter_getContactPointX
(JNIEnv * env, jobject thiz, jint contactIndex) {
cpArbiter* arb = (cpArbiter*)env->GetIntField(thiz, g_fid_Arbiter_mPointer);
cpVect v = cpArbiterGetPoint(arb, contactIndex);
return v.x;
}
static int cpArbiter_getPoint(lua_State *L) {
cpArbiter *arb = toarbiter(L);
int i = luaL_checkint(L, 2);
push_cpVect(L, cpArbiterGetPoint(arb, i));
return 2;
}
int modArbiterGetPoint(INSTANCE * my, int * params){
cpVect v=cpArbiterGetPoint((cpArbiter *)params[0],params[1]);
*(float*)params[2]=v.x;
*(float*)params[3]=v.y;
return 1;
}
