Files
LuaCsForBarotraumaEP/Farseer Physics Engine 3.5/Dynamics/ContactManager.cs

445 lines
13 KiB
C#

/*
* Farseer Physics Engine:
* Copyright (c) 2012 Ian Qvist
*
* Original source Box2D:
* Copyright (c) 2006-2011 Erin Catto http://www.box2d.org
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
//#define USE_ACTIVE_CONTACT_SET
using System.Collections.Generic;
using FarseerPhysics.Collision;
using FarseerPhysics.Dynamics.Contacts;
namespace FarseerPhysics.Dynamics
{
public class ContactManager
{
/// <summary>
/// Fires when a contact is created
/// </summary>
public BeginContactDelegate BeginContact;
public IBroadPhase BroadPhase;
/// <summary>
/// The filter used by the contact manager.
/// </summary>
public CollisionFilterDelegate ContactFilter;
public List<Contact> ContactList = new List<Contact>(128);
#if USE_ACTIVE_CONTACT_SET
/// <summary>
/// The set of active contacts.
/// </summary>
public HashSet<Contact> ActiveContacts = new HashSet<Contact>();
/// <summary>
/// A temporary copy of active contacts that is used during updates so
/// the hash set can have members added/removed during the update.
/// This list is cleared after every update.
/// </summary>
List<Contact> ActiveList = new List<Contact>();
#endif
/// <summary>
/// Fires when a contact is deleted
/// </summary>
public EndContactDelegate EndContact;
/// <summary>
/// Fires when the broadphase detects that two Fixtures are close to each other.
/// </summary>
public BroadphaseDelegate OnBroadphaseCollision;
/// <summary>
/// Fires after the solver has run
/// </summary>
public PostSolveDelegate PostSolve;
/// <summary>
/// Fires before the solver runs
/// </summary>
public PreSolveDelegate PreSolve;
internal ContactManager(IBroadPhase broadPhase)
{
BroadPhase = broadPhase;
OnBroadphaseCollision = AddPair;
}
// Broad-phase callback.
private void AddPair(ref FixtureProxy proxyA, ref FixtureProxy proxyB)
{
Fixture fixtureA = proxyA.Fixture;
Fixture fixtureB = proxyB.Fixture;
int indexA = proxyA.ChildIndex;
int indexB = proxyB.ChildIndex;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
// Are the fixtures on the same body?
if (bodyA == bodyB)
{
return;
}
// Does a contact already exist?
ContactEdge edge = bodyB.ContactList;
while (edge != null)
{
if (edge.Other == bodyA)
{
Fixture fA = edge.Contact.FixtureA;
Fixture fB = edge.Contact.FixtureB;
int iA = edge.Contact.ChildIndexA;
int iB = edge.Contact.ChildIndexB;
if (fA == fixtureA && fB == fixtureB && iA == indexA && iB == indexB)
{
// A contact already exists.
return;
}
if (fA == fixtureB && fB == fixtureA && iA == indexB && 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 default filter
if (ShouldCollide(fixtureA, fixtureB) == false)
return;
// Check user filtering.
if (ContactFilter != null && ContactFilter(fixtureA, fixtureB) == false)
return;
//FPE feature: BeforeCollision delegate
if (fixtureA.BeforeCollision != null && fixtureA.BeforeCollision(fixtureA, fixtureB) == false)
return;
if (fixtureB.BeforeCollision != null && fixtureB.BeforeCollision(fixtureB, fixtureA) == false)
return;
// Call the factory.
Contact c = Contact.Create(fixtureA, indexA, fixtureB, indexB);
if (c == null)
return;
// Contact creation may swap fixtures.
fixtureA = c.FixtureA;
fixtureB = c.FixtureB;
bodyA = fixtureA.Body;
bodyB = fixtureB.Body;
// Insert into the world.
ContactList.Add(c);
#if USE_ACTIVE_CONTACT_SET
ActiveContacts.Add(c);
#endif
// Connect to island graph.
// Connect to body A
c._nodeA.Contact = c;
c._nodeA.Other = bodyB;
c._nodeA.Prev = null;
c._nodeA.Next = bodyA.ContactList;
if (bodyA.ContactList != null)
{
bodyA.ContactList.Prev = c._nodeA;
}
bodyA.ContactList = c._nodeA;
// Connect to body B
c._nodeB.Contact = c;
c._nodeB.Other = bodyA;
c._nodeB.Prev = null;
c._nodeB.Next = bodyB.ContactList;
if (bodyB.ContactList != null)
{
bodyB.ContactList.Prev = c._nodeB;
}
bodyB.ContactList = c._nodeB;
// Wake up the bodies
if (fixtureA.IsSensor == false && fixtureB.IsSensor == false)
{
bodyA.Awake = true;
bodyB.Awake = true;
}
}
internal void FindNewContacts()
{
BroadPhase.UpdatePairs(OnBroadphaseCollision);
}
internal void Destroy(Contact contact)
{
Fixture fixtureA = contact.FixtureA;
Fixture fixtureB = contact.FixtureB;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
if (contact.IsTouching)
{
//Report the separation to both participants:
if (fixtureA != null && fixtureA.OnSeparation != null)
fixtureA.OnSeparation(fixtureA, fixtureB);
//Reverse the order of the reported fixtures. The first fixture is always the one that the
//user subscribed to.
if (fixtureB != null && fixtureB.OnSeparation != null)
fixtureB.OnSeparation(fixtureB, fixtureA);
if (EndContact != null)
EndContact(contact);
}
// Remove from the world.
ContactList.Remove(contact);
// Remove from body 1
if (contact._nodeA.Prev != null)
{
contact._nodeA.Prev.Next = contact._nodeA.Next;
}
if (contact._nodeA.Next != null)
{
contact._nodeA.Next.Prev = contact._nodeA.Prev;
}
if (contact._nodeA == bodyA.ContactList)
{
bodyA.ContactList = contact._nodeA.Next;
}
// Remove from body 2
if (contact._nodeB.Prev != null)
{
contact._nodeB.Prev.Next = contact._nodeB.Next;
}
if (contact._nodeB.Next != null)
{
contact._nodeB.Next.Prev = contact._nodeB.Prev;
}
if (contact._nodeB == bodyB.ContactList)
{
bodyB.ContactList = contact._nodeB.Next;
}
#if USE_ACTIVE_CONTACT_SET
if (ActiveContacts.Contains(contact))
{
ActiveContacts.Remove(contact);
}
#endif
contact.Destroy();
}
internal void Collide()
{
// Update awake contacts.
#if USE_ACTIVE_CONTACT_SET
ActiveList.AddRange(ActiveContacts);
foreach (var c in ActiveList)
{
#else
for (int i = 0; i < ContactList.Count; i++)
{
Contact c = ContactList[i];
#endif
Fixture fixtureA = c.FixtureA;
Fixture fixtureB = c.FixtureB;
int indexA = c.ChildIndexA;
int indexB = c.ChildIndexB;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
//Do no try to collide disabled bodies
if (!bodyA.Enabled || !bodyB.Enabled)
continue;
// Is this contact flagged for filtering?
if (c.FilterFlag)
{
// Should these bodies collide?
if (bodyB.ShouldCollide(bodyA) == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// Check default filtering
if (ShouldCollide(fixtureA, fixtureB) == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// Check user filtering.
if (ContactFilter != null && ContactFilter(fixtureA, fixtureB) == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// Clear the filtering flag.
c.FilterFlag = false;
}
bool activeA = bodyA.Awake && bodyA.BodyType != BodyType.Static;
bool activeB = bodyB.Awake && bodyB.BodyType != BodyType.Static;
// At least one body must be awake and it must be dynamic or kinematic.
if (activeA == false && activeB == false)
{
#if USE_ACTIVE_CONTACT_SET
ActiveContacts.Remove(c);
#endif
continue;
}
int proxyIdA = fixtureA.Proxies[indexA].ProxyId;
int proxyIdB = fixtureB.Proxies[indexB].ProxyId;
bool overlap = BroadPhase.TestOverlap(proxyIdA, proxyIdB);
// Here we destroy contacts that cease to overlap in the broad-phase.
if (overlap == false)
{
Contact cNuke = c;
Destroy(cNuke);
continue;
}
// The contact persists.
c.Update(this);
}
#if USE_ACTIVE_CONTACT_SET
ActiveList.Clear();
#endif
}
private static bool ShouldCollide(Fixture fixtureA, Fixture fixtureB)
{
if (Settings.UseFPECollisionCategories)
{
if ((fixtureA.CollisionGroup == fixtureB.CollisionGroup) &&
fixtureA.CollisionGroup != 0 && fixtureB.CollisionGroup != 0)
return false;
if (((fixtureA.CollisionCategories & fixtureB.CollidesWith) ==
Category.None) &
((fixtureB.CollisionCategories & fixtureA.CollidesWith) ==
Category.None))
return false;
if (fixtureA.IsFixtureIgnored(fixtureB) ||
fixtureB.IsFixtureIgnored(fixtureA))
return false;
return true;
}
if (fixtureA.CollisionGroup == fixtureB.CollisionGroup &&
fixtureA.CollisionGroup != 0)
{
return fixtureA.CollisionGroup > 0;
}
bool collide = (fixtureA.CollidesWith & fixtureB.CollisionCategories) != 0 &&
(fixtureA.CollisionCategories & fixtureB.CollidesWith) != 0;
if (collide)
{
if (fixtureA.IsFixtureIgnored(fixtureB) ||
fixtureB.IsFixtureIgnored(fixtureA))
{
return false;
}
}
return collide;
}
internal void UpdateContacts(ContactEdge contactEdge, bool value)
{
#if USE_ACTIVE_CONTACT_SET
if(value)
{
while(contactEdge != null)
{
var c = contactEdge.Contact;
if (!ActiveContacts.Contains(c))
{
ActiveContacts.Add(c);
}
contactEdge = contactEdge.Next;
}
}
else
{
while (contactEdge != null)
{
var c = contactEdge.Contact;
if (!contactEdge.Other.Awake)
{
if (ActiveContacts.Contains(c))
{
ActiveContacts.Remove(c);
}
}
contactEdge = contactEdge.Next;
}
}
#endif
}
#if USE_ACTIVE_CONTACT_SET
internal void RemoveActiveContact(Contact contact)
{
if (ActiveContacts.Contains(contact))
ActiveContacts.Remove(contact);
}
#endif
}
}