/*******************************************************************************
* Copyright (c) 2011, Daniel Murphy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
******************************************************************************/
package org.jbox2d.dynamics;
import org.jbox2d.callbacks.ContactFilter;
import org.jbox2d.callbacks.ContactListener;
import org.jbox2d.callbacks.PairCallback;
import org.jbox2d.collision.broadphase.BroadPhase;
import org.jbox2d.dynamics.contacts.Contact;
import org.jbox2d.dynamics.contacts.ContactEdge;
/** Delegate of World.
*
* @author Daniel Murphy */
public class ContactManager implements PairCallback {
public BroadPhase m_broadPhase;
public Contact m_contactList;
public int m_contactCount;
public ContactFilter m_contactFilter;
public ContactListener m_contactListener;
private final World pool;
public ContactManager (World argPool) {
m_contactList = null;
m_contactCount = 0;
m_contactFilter = new ContactFilter();
m_contactListener = null;
m_broadPhase = new BroadPhase();
pool = argPool;
}
/** Broad-phase callback.
*
* @param proxyUserDataA
* @param proxyUserDataB */
public void addPair (Object proxyUserDataA, Object proxyUserDataB) {
FixtureProxy proxyA = (FixtureProxy)proxyUserDataA;
FixtureProxy proxyB = (FixtureProxy)proxyUserDataB;
Fixture fixtureA = proxyA.fixture;
Fixture fixtureB = proxyB.fixture;
int indexA = proxyA.childIndex;
int indexB = proxyB.childIndex;
Body bodyA = fixtureA.getBody();
Body bodyB = fixtureB.getBody();
// Are the fixtures on the same body?
if (bodyA == bodyB) {
return;
}
// TODO_ERIN use a hash table to remove a potential bottleneck when both
// bodies have a lot of contacts.
// Does a contact already exist?
ContactEdge edge = bodyB.getContactList();
while (edge != null) {
if (edge.other == bodyA) {
Fixture fA = edge.contact.getFixtureA();
Fixture fB = edge.contact.getFixtureB();
int iA = edge.contact.getChildIndexA();
int iB = edge.contact.getChildIndexB();
if (fA == fixtureA && iA == indexA && fB == fixtureB && iB == indexB) {
// A contact already exists.
return;
}
if (fA == fixtureB && iA == indexB && fB == fixtureA && iB == indexA) {
// A contact already exists.
return;
}
}
edge = edge.next;
}
// Does a joint override collision? is at least one body dynamic?
if (bodyB.shouldCollide(bodyA) == false) {
return;
}
// Check user filtering.
if (m_contactFilter != null && m_contactFilter.shouldCollide(fixtureA, fixtureB) == false) {
return;
}
// Call the factory.
Contact c = pool.popContact(fixtureA, indexA, fixtureB, indexB);
if (c == null) {
return;
}
// Contact creation may swap fixtures.
fixtureA = c.getFixtureA();
fixtureB = c.getFixtureB();
indexA = c.getChildIndexA();
indexB = c.getChildIndexB();
bodyA = fixtureA.getBody();
bodyB = fixtureB.getBody();
// Insert into the world.
c.m_prev = null;
c.m_next = m_contactList;
if (m_contactList != null) {
m_contactList.m_prev = c;
}
m_contactList = c;
// Connect to island graph.
// Connect to body A
c.m_nodeA.contact = c;
c.m_nodeA.other = bodyB;
c.m_nodeA.prev = null;
c.m_nodeA.next = bodyA.m_contactList;
if (bodyA.m_contactList != null) {
bodyA.m_contactList.prev = c.m_nodeA;
}
bodyA.m_contactList = c.m_nodeA;
// Connect to body B
c.m_nodeB.contact = c;
c.m_nodeB.other = bodyA;
c.m_nodeB.prev = null;
c.m_nodeB.next = bodyB.m_contactList;
if (bodyB.m_contactList != null) {
bodyB.m_contactList.prev = c.m_nodeB;
}
bodyB.m_contactList = c.m_nodeB;
// wake up the bodies
bodyA.setAwake(true);
bodyB.setAwake(true);
++m_contactCount;
}
public void findNewContacts () {
m_broadPhase.updatePairs(this);
}
public void destroy (Contact c) {
Fixture fixtureA = c.getFixtureA();
Fixture fixtureB = c.getFixtureB();
Body bodyA = fixtureA.getBody();
Body bodyB = fixtureB.getBody();
if (m_contactListener != null && c.isTouching()) {
m_contactListener.endContact(c);
}
// Remove from the world.
if (c.m_prev != null) {
c.m_prev.m_next = c.m_next;
}
if (c.m_next != null) {
c.m_next.m_prev = c.m_prev;
}
if (c == m_contactList) {
m_contactList = c.m_next;
}
// Remove from body 1
if (c.m_nodeA.prev != null) {
c.m_nodeA.prev.next = c.m_nodeA.next;
}
if (c.m_nodeA.next != null) {
c.m_nodeA.next.prev = c.m_nodeA.prev;
}
if (c.m_nodeA == bodyA.m_contactList) {
bodyA.m_contactList = c.m_nodeA.next;
}
// Remove from body 2
if (c.m_nodeB.prev != null) {
c.m_nodeB.prev.next = c.m_nodeB.next;
}
if (c.m_nodeB.next != null) {
c.m_nodeB.next.prev = c.m_nodeB.prev;
}
if (c.m_nodeB == bodyB.m_contactList) {
bodyB.m_contactList = c.m_nodeB.next;
}
// Call the factory.
pool.pushContact(c);
--m_contactCount;
}
/** This is the top level collision call for the time step. Here all the narrow phase collision is processed for the world
* contact list. */
public void collide () {
// Update awake contacts.
Contact c = m_contactList;
while (c != null) {
Fixture fixtureA = c.getFixtureA();
Fixture fixtureB = c.getFixtureB();
int indexA = c.getChildIndexA();
int indexB = c.getChildIndexB();
Body bodyA = fixtureA.getBody();
Body bodyB = fixtureB.getBody();
// is this contact flagged for filtering?
if ((c.m_flags & Contact.FILTER_FLAG) == Contact.FILTER_FLAG) {
// Should these bodies collide?
if (bodyB.shouldCollide(bodyA) == false) {
Contact cNuke = c;
c = cNuke.getNext();
destroy(cNuke);
continue;
}
// Check user filtering.
if (m_contactFilter != null && m_contactFilter.shouldCollide(fixtureA, fixtureB) == false) {
Contact cNuke = c;
c = cNuke.getNext();
destroy(cNuke);
continue;
}
// Clear the filtering flag.
c.m_flags &= ~Contact.FILTER_FLAG;
}
boolean activeA = bodyA.isAwake() && bodyA.m_type != BodyType.STATIC;
boolean activeB = bodyB.isAwake() && bodyB.m_type != BodyType.STATIC;
// At least one body must be awake and it must be dynamic or kinematic.
if (activeA == false && activeB == false) {
c = c.getNext();
continue;
}
int proxyIdA = fixtureA.m_proxies[indexA].proxyId;
int proxyIdB = fixtureB.m_proxies[indexB].proxyId;
boolean overlap = m_broadPhase.testOverlap(proxyIdA, proxyIdB);
// Here we destroy contacts that cease to overlap in the broad-phase.
if (overlap == false) {
Contact cNuke = c;
c = cNuke.getNext();
destroy(cNuke);
continue;
}
// The contact persists.
c.update(m_contactListener);
c = c.getNext();
}
}
}