use of com.almasb.fxgl.physics.box2d.dynamics.Fixture in project FXGL by AlmasB.
the class ContactSolver method init.
public void init(ContactSolverDef def) {
TimeStep step = def.step;
m_count = def.count;
if (m_positionConstraints.length < m_count) {
ContactPositionConstraint[] old = m_positionConstraints;
m_positionConstraints = new ContactPositionConstraint[Math.max(old.length * 2, m_count)];
System.arraycopy(old, 0, m_positionConstraints, 0, old.length);
for (int i = old.length; i < m_positionConstraints.length; i++) {
m_positionConstraints[i] = new ContactPositionConstraint();
}
}
if (m_velocityConstraints.length < m_count) {
ContactVelocityConstraint[] old = m_velocityConstraints;
m_velocityConstraints = new ContactVelocityConstraint[Math.max(old.length * 2, m_count)];
System.arraycopy(old, 0, m_velocityConstraints, 0, old.length);
for (int i = old.length; i < m_velocityConstraints.length; i++) {
m_velocityConstraints[i] = new ContactVelocityConstraint();
}
}
m_positions = def.positions;
m_velocities = def.velocities;
m_contacts = def.contacts;
for (int i = 0; i < m_count; ++i) {
final Contact contact = m_contacts[i];
final Fixture fixtureA = contact.m_fixtureA;
final Fixture fixtureB = contact.m_fixtureB;
final Shape shapeA = fixtureA.getShape();
final Shape shapeB = fixtureB.getShape();
final float radiusA = shapeA.getRadius();
final float radiusB = shapeB.getRadius();
final Body bodyA = fixtureA.getBody();
final Body bodyB = fixtureB.getBody();
final Manifold manifold = contact.getManifold();
int pointCount = manifold.pointCount;
assert pointCount > 0;
ContactVelocityConstraint vc = m_velocityConstraints[i];
vc.friction = contact.getFriction();
vc.restitution = contact.getRestitution();
vc.tangentSpeed = contact.getTangentSpeed();
vc.indexA = bodyA.m_islandIndex;
vc.indexB = bodyB.m_islandIndex;
vc.invMassA = bodyA.m_invMass;
vc.invMassB = bodyB.m_invMass;
vc.invIA = bodyA.m_invI;
vc.invIB = bodyB.m_invI;
vc.contactIndex = i;
vc.pointCount = pointCount;
vc.K.setZero();
vc.normalMass.setZero();
ContactPositionConstraint pc = m_positionConstraints[i];
pc.indexA = bodyA.m_islandIndex;
pc.indexB = bodyB.m_islandIndex;
pc.invMassA = bodyA.m_invMass;
pc.invMassB = bodyB.m_invMass;
pc.localCenterA.set(bodyA.m_sweep.localCenter);
pc.localCenterB.set(bodyB.m_sweep.localCenter);
pc.invIA = bodyA.m_invI;
pc.invIB = bodyB.m_invI;
pc.localNormal.set(manifold.localNormal);
pc.localPoint.set(manifold.localPoint);
pc.pointCount = pointCount;
pc.radiusA = radiusA;
pc.radiusB = radiusB;
pc.type = manifold.type;
for (int j = 0; j < pointCount; j++) {
ManifoldPoint cp = manifold.points[j];
VelocityConstraintPoint vcp = vc.points[j];
if (step.warmStarting) {
vcp.normalImpulse = step.dtRatio * cp.normalImpulse;
vcp.tangentImpulse = step.dtRatio * cp.tangentImpulse;
} else {
vcp.normalImpulse = 0;
vcp.tangentImpulse = 0;
}
vcp.rA.setZero();
vcp.rB.setZero();
vcp.normalMass = 0;
vcp.tangentMass = 0;
vcp.velocityBias = 0;
pc.localPoints[j].x = cp.localPoint.x;
pc.localPoints[j].y = cp.localPoint.y;
}
}
}
Aggregations