public void Collide()
{
for (Contact contact = this._world._contactList; contact != null; contact = contact.GetNext())
{
Body body = contact.GetShape1().GetBody();
Body body2 = contact.GetShape2().GetBody();
if (!body.IsSleeping() || !body2.IsSleeping())
{
contact.Update(this._world._contactListener);
}
}
}
// 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.
for (Contact c = _world._contactList; c != null; c = c.GetNext())
{
Body body1 = c.GetShape1().GetBody();
Body body2 = c.GetShape2().GetBody();
if (body1.IsSleeping() && body2.IsSleeping())
{
continue;
}
c.Update(_world._contactListener);
}
}
// 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.
for (Contact c = _world._contactList; c != null; c = c.GetNext())
{
Body bodyA = c._fixtureA.Body;
Body bodyB = c._fixtureB.Body;
if (bodyA.IsSleeping() && bodyB.IsSleeping())
{
continue;
}
c.Update(_world._contactListener);
}
}
// 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 = _contactList;
while (c != null)
{
Fixture fixtureA = c.GetFixtureA();
Fixture fixtureB = c.GetFixtureB();
Body bodyA = fixtureA.GetBody();
Body bodyB = fixtureB.GetBody();
if (bodyA.IsSleeping() && bodyB.IsSleeping())
{
c = c.GetNext();
continue;
}
// Is this contact flagged for filtering?
if ((c.Flags & ContactFlag.FilterFlag) == ContactFlag.FilterFlag)
{
//TODO: The following code (next 4 if blocks) use a class and thus copy by ref. It might expect to copy by value
// Are both bodies static?
if (bodyA.IsStatic() && bodyB.IsStatic())
{
Contact cNuke = c;
c = cNuke.GetNext();
Destroy(cNuke);
continue;
}
// Does a joint override collision?
if (bodyB.IsConnected(bodyA))
{
Contact cNuke = c;
c = cNuke.GetNext();
Destroy(cNuke);
continue;
}
// Check user filtering.
if (_contactFilter.ShouldCollide(fixtureA, fixtureB) == false)
{
Contact cNuke = c;
c = cNuke.GetNext();
Destroy(cNuke);
continue;
}
// Clear the filtering flag.
c.Flags &= ~ContactFlag.FilterFlag;
}
int proxyIdA = fixtureA.ProxyId;
int proxyIdB = fixtureB.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;
c = cNuke.GetNext();
Destroy(cNuke);
continue;
}
// The contact persists.
c.Update(_contactListener);
c = c.GetNext();
}
}
// Find TOI contacts and solve them.
private void SolveTOI(TimeStep step)
{
// Reserve an island and a queue for TOI island solution.
Island island = new Island(_bodyCount,
Settings.MaxTOIContactsPerIsland,
Settings.MaxTOIJointsPerIsland,
_contactManager._contactListener);
//Simple one pass queue
//Relies on the fact that we're only making one pass
//through and each body can only be pushed/popped once.
//To push:
// queue[queueStart+queueSize++] = newElement;
//To pop:
// poppedElement = queue[queueStart++];
// --queueSize;
int queueCapacity = _bodyCount;
Body[] queue = new Body[queueCapacity];
for (Body b = _bodyList; b != null; b = b._next)
{
b._flags &= ~Body.BodyFlags.Island;
b._sweep.T0 = 0.0f;
}
for (Contact c = _contactManager._contactList; c != null; c = c.Next)
{
// Invalidate TOI
c.Flags &= ~(ContactFlag.ToiFlag | ContactFlag.IslandFlag);
}
for (Joint j = _jointList; j != null; j = j._next)
{
j._islandFlag = false;
}
// Find TOI events and solve them.
for (; ;)
{
// Find the first TOI.
Contact minContact = null;
float minTOI = 1.0f;
for (Contact c = _contactManager._contactList; c != null; c = c.Next)
{
// Can this contact generate a solid TOI contact?
if (c.IsSolid() == false || c.IsContinuous() == false)
{
continue;
}
// TODO_ERIN keep a counter on the contact, only respond to M TOIs per contact.
float toi = 1.0f;
if ((c.Flags & ContactFlag.ToiFlag) != 0)
{
// This contact has a valid cached TOI.
toi = c.Toi;
}
else
{
// Compute the TOI for this contact.
Fixture s1 = c.GetFixtureA();
Fixture s2 = c.GetFixtureB();
Body b1 = s1.GetBody();
Body b2 = s2.GetBody();
if ((b1.IsStatic() || b1.IsSleeping()) && (b2.IsStatic() || b2.IsSleeping()))
{
continue;
}
// Put the sweeps onto the same time interval.
float t0 = b1._sweep.T0;
if (b1._sweep.T0 < b2._sweep.T0)
{
t0 = b2._sweep.T0;
b1._sweep.Advance(t0);
}
else if (b2._sweep.T0 < b1._sweep.T0)
{
t0 = b1._sweep.T0;
b2._sweep.Advance(t0);
}
Box2DXDebug.Assert(t0 < 1.0f);
// Compute the time of impact.
toi = c.ComputeTOI(b1._sweep, b2._sweep);
Box2DXDebug.Assert(0.0f <= toi && toi <= 1.0f);
// If the TOI is in range ...
if (0.0f < toi && toi < 1.0f)
{
// Interpolate on the actual range.
toi = Math.Min((1.0f - toi) * t0 + toi, 1.0f);
}
c.Toi = toi;
c.Flags |= ContactFlag.ToiFlag;
}
if (Settings.FLT_EPSILON < toi && toi < minTOI)
{
// This is the minimum TOI found so far.
minContact = c;
minTOI = toi;
}
}
if (minContact == null || 1.0f - 100.0f * Settings.FLT_EPSILON < minTOI)
{
// No more TOI events. Done!
break;
}
// Advance the bodies to the TOI.
Fixture f1 = minContact.GetFixtureA();
Fixture f2 = minContact.GetFixtureB();
Body b3 = f1.GetBody();
Body b4 = f2.GetBody();
Sweep backup1 = b3._sweep;
Sweep backup2 = b4._sweep;
b3.Advance(minTOI);
b4.Advance(minTOI);
// The TOI contact likely has some new contact points.
minContact.Update(_contactManager._contactListener);
minContact.Flags &= ~ContactFlag.ToiFlag;
// Is the contact solid?
if (minContact.IsSolid() == false)
{
// Restore the sweeps.
b3._sweep = backup1;
b4._sweep = backup2;
b3.SynchronizeTransform();
b4.SynchronizeTransform();
continue;
}
// Did numerical issues prevent a contact point from being generated?
if (minContact.IsTouching() == false)
{
// Give up on this TOI.
continue;
}
// Build the TOI island. We need a dynamic seed.
Body seed = b3;
if (seed.IsStatic())
{
seed = b4;
}
// Reset island and queue.
island.Clear();
int queueStart = 0; // starting index for queue
int queueSize = 0; // elements in queue
queue[queueStart + queueSize++] = seed;
seed._flags |= Body.BodyFlags.Island;
// Perform a breadth first search (BFS) on the contact/joint graph.
while (queueSize > 0)
{
// Grab the next body off the stack and add it to the island.
Body b = queue[queueStart++];
--queueSize;
island.Add(ref b);
// Make sure the body is awake.
b._flags &= ~Body.BodyFlags.Sleep;
// To keep islands as small as possible, we don't
// propagate islands across static bodies.
if (b.IsStatic())
{
continue;
}
// Search all contacts connected to this body.
for (ContactEdge cEdge = b._contactList; cEdge != null; cEdge = cEdge.Next)
{
// Does the TOI island still have space for contacts?
if (island.ContactCount == island.ContactCapacity)
{
break;
}
// Has this contact already been added to an island? Skip slow or non-solid contacts.
if ((cEdge.Contact.Flags & ContactFlag.IslandFlag) != 0)
{
continue;
}
// Is this contact touching? For performance we are not updating this contact.
if (cEdge.Contact.IsSolid() == false || cEdge.Contact.IsTouching() == false)
{
continue;
}
island.Add(ref cEdge.Contact);
cEdge.Contact.Flags |= ContactFlag.IslandFlag;
// Update other body.
Body other = cEdge.Other;
// Was the other body already added to this island?
if ((other._flags & Body.BodyFlags.Island) != 0)
{
continue;
}
// March forward, this can do no harm since this is the min TOI.
if (other.IsStatic() == false)
{
other.Advance(minTOI);
other.WakeUp();
}
Box2DXDebug.Assert(queueStart + queueSize < queueCapacity);
queue[queueStart + queueSize] = other;
++queueSize;
other._flags |= Body.BodyFlags.Island;
}
for (JointEdge jEdge = b._jointList; jEdge != null; jEdge = jEdge.Next)
{
if (island.JointCount == island.JointCapacity)
{
continue;
}
if (jEdge.Joint._islandFlag == true)
{
continue;
}
island.Add(jEdge.Joint);
jEdge.Joint._islandFlag = true;
Body other = jEdge.Other;
if ((other._flags & Body.BodyFlags.Island) != 0)
{
continue;
}
if (!other.IsStatic())
{
other.Advance(minTOI);
other.WakeUp();
}
Box2DXDebug.Assert(queueStart + queueSize < queueCapacity);
queue[queueStart + queueSize] = other;
++queueSize;
other._flags |= Body.BodyFlags.Island;
}
}
TimeStep subStep;
subStep.WarmStarting = false;
subStep.Dt = (1.0f - minTOI) * step.Dt;
subStep.Inv_Dt = 1.0f / subStep.Dt;
subStep.DtRatio = 0.0f;
subStep.VelocityIterations = step.VelocityIterations;
subStep.PositionIterations = step.PositionIterations;
island.SolveTOI(ref subStep);
// Post solve cleanup.
for (int i = 0; i < island.BodyCount; ++i)
{
// Allow bodies to participate in future TOI islands.
Body b = island.Bodies[i];
b._flags &= ~Body.BodyFlags.Island;
if ((b._flags & Body.BodyFlags.Sleep) != 0)
{
continue;
}
if (b.IsStatic())
{
continue;
}
b.SynchronizeFixtures();
// Invalidate all contact TOIs associated with this body. Some of these
// may not be in the island because they were not touching.
for (ContactEdge ce = b._contactList; ce != null; ce = ce.Next)
{
ce.Contact.Flags &= ~ContactFlag.ToiFlag;
}
}
for (int i = 0; i < island.ContactCount; ++i)
{
// Allow contacts to participate in future TOI islands.
Contact c = island.Contacts[i];
c.Flags &= ~(ContactFlag.ToiFlag | ContactFlag.IslandFlag);
}
for (int i = 0; i < island.JointCount; ++i)
{
// Allow joints to participate in future TOI islands.
Joint j = island.Joints[i];
j._islandFlag = false;
}
// Commit fixture proxy movements to the broad-phase so that new contacts are created.
// Also, some contacts can be destroyed.
_contactManager.FindNewContacts();
}
queue = null;
}
public void DrawDebugData()
{
if (_debugDraw == null)
{
return;
}
DebugDraw.DrawFlags flags = _debugDraw.Flags;
if ((flags & DebugDraw.DrawFlags.Shape) != 0)
{
for (Body b = _bodyList; b != null; b = b.GetNext())
{
Transform xf = b.GetTransform();
for (Fixture f = b.GetFixtureList(); f != null; f = f.GetNext())
{
if (b.IsStatic())
{
DrawShape(f, xf, new Color(0.5f, 0.9f, 0.5f));
}
else if (b.IsSleeping())
{
DrawShape(f, xf, new Color(0.5f, 0.5f, 0.9f));
}
else
{
DrawShape(f, xf, new Color(0.9f, 0.9f, 0.9f));
}
}
}
}
if ((flags & DebugDraw.DrawFlags.Joint) != 0)
{
for (Joint j = _jointList; j != null; j = j.GetNext())
{
if (j.GetType() != JointType.MouseJoint)
{
DrawJoint(j);
}
}
}
if ((flags & DebugDraw.DrawFlags.Pair) != 0)
{
// TODO_ERIN
}
if ((flags & DebugDraw.DrawFlags.Aabb) != 0)
{
Color color = new Color(0.9f, 0.3f, 0.9f);
BroadPhase bp = _contactManager._broadPhase;
for (Body b = _bodyList; b != null; b = b.GetNext())
{
for (Fixture f = b.GetFixtureList(); f != null; f = f.GetNext())
{
AABB aabb = bp.GetFatAABB(f.ProxyId);
Vec2[] vs = new Vec2[4];
vs[0].Set(aabb.LowerBound.X, aabb.LowerBound.Y);
vs[1].Set(aabb.UpperBound.X, aabb.LowerBound.Y);
vs[2].Set(aabb.UpperBound.X, aabb.UpperBound.Y);
vs[3].Set(aabb.LowerBound.X, aabb.UpperBound.Y);
_debugDraw.DrawPolygon(vs, 4, color);
}
}
}
if ((flags & DebugDraw.DrawFlags.CenterOfMass) != 0)
{
for (Body b = _bodyList; b != null; b = b.GetNext())
{
Transform xf = b.GetTransform();
xf.Position = b.GetWorldCenter();
_debugDraw.DrawXForm(xf);
}
}
}