internal bool CompareTo(Fixture fixture)
{
return (
CollidesWith == fixture.CollidesWith &&
CollisionCategories == fixture.CollisionCategories &&
CollisionGroup == fixture.CollisionGroup &&
Friction == fixture.Friction &&
IsSensor == fixture.IsSensor &&
Restitution == fixture.Restitution &&
Shape.CompareTo(fixture.Shape) &&
UserData == fixture.UserData);
}
/// <summary>
/// Destroy a fixture. This removes the fixture from the broad-phase and
/// destroys all contacts associated with this fixture. This will
/// automatically adjust the mass of the body if the body is dynamic and the
/// fixture has positive density.
/// All fixtures attached to a body are implicitly destroyed when the body is destroyed.
/// Warning: This function is locked during callbacks.
/// </summary>
/// <param name="fixture">The fixture to be removed.</param>
public void DestroyFixture(Fixture fixture)
{
Debug.Assert(fixture.Body == this);
// Remove the fixture from this body's singly linked list.
Debug.Assert(FixtureList.Count > 0);
// You tried to remove a fixture that not present in the fixturelist.
Debug.Assert(FixtureList.Contains(fixture));
// Destroy any contacts associated with the fixture.
ContactEdge edge = ContactList;
while (edge != null)
{
Contact c = edge.Contact;
edge = edge.Next;
Fixture fixtureA = c.FixtureA;
Fixture fixtureB = c.FixtureB;
if (fixture == fixtureA || fixture == fixtureB)
{
// This destroys the contact and removes it from
// this body's contact list.
World.ContactManager.Destroy(c);
}
}
if ((Flags & BodyFlags.Enabled) == BodyFlags.Enabled)
{
IBroadPhase broadPhase = World.ContactManager.BroadPhase;
fixture.DestroyProxies(broadPhase);
}
FixtureList.Remove(fixture);
fixture.Destroy();
fixture.Body = null;
ResetMassData();
}
/// <summary>
/// Determines whether collisions are ignored between this fixture and the provided fixture.
/// </summary>
/// <param name="fixture">The fixture.</param>
/// <returns>
/// <c>true</c> if the fixture is ignored; otherwise, <c>false</c>.
/// </returns>
public bool IsFixtureIgnored(Fixture fixture)
{
if (_collisionIgnores == null)
return false;
if (_collisionIgnores.ContainsKey(fixture.FixtureId))
return _collisionIgnores[fixture.FixtureId];
return false;
}
/// <summary>
/// Restores collisions between this fixture and the provided fixture.
/// </summary>
/// <param name="fixture">The fixture.</param>
public void RestoreCollisionWith(Fixture fixture)
{
if (_collisionIgnores == null)
return;
if (_collisionIgnores.ContainsKey(fixture.FixtureId))
{
_collisionIgnores[fixture.FixtureId] = false;
Refilter();
}
}
public Fixture Clone(PhysicsBody body)
{
Fixture fixture = new Fixture();
fixture.Body = body;
if (Settings.ConserveMemory)
fixture.Shape = Shape;
else
fixture.Shape = Shape.Clone();
fixture.UserData = UserData;
fixture.Restitution = Restitution;
fixture.Friction = Friction;
fixture.IsSensor = IsSensor;
fixture._collisionGroup = CollisionGroup;
fixture._collisionCategories = CollisionCategories;
fixture._collidesWith = CollidesWith;
if (_collisionIgnores != null)
{
fixture._collisionIgnores = new Dictionary<int, bool>();
foreach (KeyValuePair<int, bool> pair in _collisionIgnores)
{
fixture._collisionIgnores.Add(pair.Key, pair.Value);
}
}
fixture.RegisterFixture();
return fixture;
}
/// <summary>
/// Ignores collisions between this fixture and the provided fixture.
/// </summary>
/// <param name="fixture">The fixture.</param>
public void IgnoreCollisionWith(Fixture fixture)
{
if (_collisionIgnores == null)
_collisionIgnores = new Dictionary<int, bool>();
if (_collisionIgnores.ContainsKey(fixture.FixtureId))
_collisionIgnores[fixture.FixtureId] = true;
else
_collisionIgnores.Add(fixture.FixtureId, true);
Refilter();
}
//Cutting a shape into two is based on the work of Daid and his prototype BoxCutter: http://www.box2d.org/forum/viewtopic.php?f=3&t=1473
/// <summary>
/// Split a fixture into 2 vertice collections using the given entry and exit-point.
/// </summary>
/// <param name="fixture">The Fixture to split</param>
/// <param name="entryPoint">The entry point - The start point</param>
/// <param name="exitPoint">The exit point - The end point</param>
/// <param name="splitSize">The size of the split. Think of this as the laser-width</param>
/// <param name="first">The first collection of vertexes</param>
/// <param name="second">The second collection of vertexes</param>
public static void SplitShape(Fixture fixture, Vector2 entryPoint, Vector2 exitPoint, float splitSize,
out Vertices first, out Vertices second)
{
Vector2 localEntryPoint = fixture.Body.GetLocalPoint(ref entryPoint);
Vector2 localExitPoint = fixture.Body.GetLocalPoint(ref exitPoint);
PolygonShape shape = fixture.Shape as PolygonShape;
if (shape == null)
{
first = new Vertices();
second = new Vertices();
return;
}
Vertices vertices = new Vertices(shape.Vertices);
Vertices[] newPolygon = new Vertices[2];
for (int i = 0; i < newPolygon.Length; i++)
{
newPolygon[i] = new Vertices(vertices.Count);
}
int[] cutAdded = { -1, -1 };
int last = -1;
for (int i = 0; i < vertices.Count; i++)
{
int n;
//Find out if this vertex is on the old or new shape.
if (Vector2.Dot(MathUtils.Cross(localExitPoint - localEntryPoint, 1), vertices[i] - localEntryPoint) > Settings.Epsilon)
n = 0;
else
n = 1;
if (last != n)
{
//If we switch from one shape to the other add the cut vertices.
if (last == 0)
{
Debug.Assert(cutAdded[0] == -1);
cutAdded[0] = newPolygon[last].Count;
newPolygon[last].Add(localExitPoint);
newPolygon[last].Add(localEntryPoint);
}
if (last == 1)
{
Debug.Assert(cutAdded[last] == -1);
cutAdded[last] = newPolygon[last].Count;
newPolygon[last].Add(localEntryPoint);
newPolygon[last].Add(localExitPoint);
}
}
newPolygon[n].Add(vertices[i]);
last = n;
}
//Add the cut in case it has not been added yet.
if (cutAdded[0] == -1)
{
cutAdded[0] = newPolygon[0].Count;
newPolygon[0].Add(localExitPoint);
newPolygon[0].Add(localEntryPoint);
}
if (cutAdded[1] == -1)
{
cutAdded[1] = newPolygon[1].Count;
newPolygon[1].Add(localEntryPoint);
newPolygon[1].Add(localExitPoint);
}
for (int n = 0; n < 2; n++)
{
Vector2 offset;
if (cutAdded[n] > 0)
{
offset = (newPolygon[n][cutAdded[n] - 1] - newPolygon[n][cutAdded[n]]);
}
else
{
offset = (newPolygon[n][newPolygon[n].Count - 1] - newPolygon[n][0]);
}
offset.Normalize();
newPolygon[n][cutAdded[n]] += splitSize * offset;
if (cutAdded[n] < newPolygon[n].Count - 2)
{
offset = (newPolygon[n][cutAdded[n] + 2] - newPolygon[n][cutAdded[n] + 1]);
}
else
{
offset = (newPolygon[n][0] - newPolygon[n][newPolygon[n].Count - 1]);
}
offset.Normalize();
newPolygon[n][cutAdded[n] + 1] += splitSize * offset;
}
first = newPolygon[0];
second = newPolygon[1];
}
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;
}
private int FindFixtureIndex(Fixture fixture)
{
for (int i = 0; i < _serializedFixtures.Count; ++i)
{
if (_serializedFixtures[i].CompareTo(fixture))
return i;
}
return -1;
}
public void Deserialize(PhysicsWorld world, Stream stream)
{
world.Clear();
XMLFragmentElement root = XMLFragmentParser.LoadFromStream(stream);
if (root.Name.ToLower() != "world")
throw new Exception();
foreach (XMLFragmentElement main in root.Elements)
{
if (main.Name.ToLower() == "gravity")
{
world.Gravity = ReadVector(main);
}
}
foreach (XMLFragmentElement shapeElement in root.Elements)
{
if (shapeElement.Name.ToLower() == "shapes")
{
foreach (XMLFragmentElement n in shapeElement.Elements)
{
if (n.Name.ToLower() != "shape")
throw new Exception();
ShapeType type = (ShapeType)Enum.Parse(typeof(ShapeType), n.Attributes[0].Value, true);
switch (type)
{
case ShapeType.Circle:
{
CircleShape shape = new CircleShape();
foreach (XMLFragmentElement sn in n.Elements)
{
switch (sn.Name.ToLower())
{
case "radius":
shape.Radius = float.Parse(sn.Value);
break;
case "position":
shape.Position = ReadVector(sn);
break;
default:
throw new Exception();
}
}
_shapes.Add(shape);
}
break;
case ShapeType.Polygon:
{
PolygonShape shape = new PolygonShape();
foreach (XMLFragmentElement sn in n.Elements)
{
switch (sn.Name.ToLower())
{
case "vertices":
{
List<Vector2> verts = new List<Vector2>();
foreach (XMLFragmentElement vert in sn.Elements)
verts.Add(ReadVector(vert));
shape.Set(new Vertices(verts.ToArray()));
}
break;
case "centroid":
shape.MassData.Centroid = ReadVector(sn);
break;
}
}
_shapes.Add(shape);
}
break;
case ShapeType.Edge:
{
EdgeShape shape = new EdgeShape();
foreach (XMLFragmentElement sn in n.Elements)
{
switch (sn.Name.ToLower())
{
case "hasvertex0":
shape.HasVertex0 = bool.Parse(sn.Value);
break;
case "hasvertex3":
shape.HasVertex0 = bool.Parse(sn.Value);
break;
case "vertex0":
shape.Vertex0 = ReadVector(sn);
break;
case "vertex1":
shape.Vertex1 = ReadVector(sn);
break;
case "vertex2":
shape.Vertex2 = ReadVector(sn);
break;
case "vertex3":
shape.Vertex3 = ReadVector(sn);
break;
default:
throw new Exception();
}
}
_shapes.Add(shape);
}
break;
}
}
}
}
foreach (XMLFragmentElement fixtureElement in root.Elements)
{
if (fixtureElement.Name.ToLower() == "fixtures")
{
foreach (XMLFragmentElement n in fixtureElement.Elements)
{
Fixture fixture = new Fixture();
if (n.Name.ToLower() != "fixture")
throw new Exception();
foreach (XMLFragmentElement sn in n.Elements)
{
switch (sn.Name.ToLower())
{
case "shape":
fixture.Shape = _shapes[int.Parse(sn.Value)];
break;
case "density":
fixture.Shape.Density = float.Parse(sn.Value);
break;
case "filterdata":
foreach (XMLFragmentElement ssn in sn.Elements)
{
switch (ssn.Name.ToLower())
{
case "categorybits":
fixture._collisionCategories = (Category)int.Parse(ssn.Value);
break;
case "maskbits":
fixture._collidesWith = (Category)int.Parse(ssn.Value);
break;
case "groupindex":
fixture._collisionGroup = short.Parse(ssn.Value);
break;
}
}
break;
case "friction":
fixture.Friction = float.Parse(sn.Value);
break;
case "issensor":
fixture.IsSensor = bool.Parse(sn.Value);
break;
case "restitution":
fixture.Restitution = float.Parse(sn.Value);
break;
case "userdata":
fixture.UserData = ReadSimpleType(sn, null, false);
break;
}
}
_fixtures.Add(fixture);
}
}
}
foreach (XMLFragmentElement bodyElement in root.Elements)
{
if (bodyElement.Name.ToLower() == "bodies")
{
foreach (XMLFragmentElement n in bodyElement.Elements)
{
PhysicsBody body = new PhysicsBody(world);
if (n.Name.ToLower() != "body")
throw new Exception();
body.BodyType = (BodyType)Enum.Parse(typeof(BodyType), n.Attributes[0].Value, true);
foreach (XMLFragmentElement sn in n.Elements)
{
switch (sn.Name.ToLower())
{
case "active":
if (bool.Parse(sn.Value))
body.Flags |= BodyFlags.Enabled;
else
body.Flags &= ~BodyFlags.Enabled;
break;
case "allowsleep":
body.SleepingAllowed = bool.Parse(sn.Value);
break;
case "angle":
{
Vector2 position = body.Position;
body.SetTransformIgnoreContacts(ref position, float.Parse(sn.Value));
}
break;
case "angulardamping":
body.AngularDamping = float.Parse(sn.Value);
break;
case "angularvelocity":
body.AngularVelocity = float.Parse(sn.Value);
break;
case "awake":
body.Awake = bool.Parse(sn.Value);
break;
case "bullet":
body.IsBullet = bool.Parse(sn.Value);
break;
case "fixedrotation":
body.FixedRotation = bool.Parse(sn.Value);
break;
case "lineardamping":
body.LinearDamping = float.Parse(sn.Value);
break;
case "linearvelocity":
body.LinearVelocity = ReadVector(sn);
break;
case "position":
{
float rotation = body.Rotation;
Vector2 position = ReadVector(sn);
body.SetTransformIgnoreContacts(ref position, rotation);
}
break;
case "userdata":
body.UserData = ReadSimpleType(sn, null, false);
break;
case "fixtures":
{
foreach (XMLFragmentElement v in sn.Elements)
{
Fixture blueprint = _fixtures[int.Parse(v.Value)];
Fixture f = new Fixture(body, blueprint.Shape);
f.Restitution = blueprint.Restitution;
f.UserData = blueprint.UserData;
f.Friction = blueprint.Friction;
f.CollidesWith = blueprint.CollidesWith;
f.CollisionCategories = blueprint.CollisionCategories;
f.CollisionGroup = blueprint.CollisionGroup;
}
break;
}
}
}
_bodies.Add(body);
}
}
}
foreach (XMLFragmentElement jointElement in root.Elements)
{
if (jointElement.Name.ToLower() == "joints")
{
foreach (XMLFragmentElement n in jointElement.Elements)
{
PhysicsJoint joint;
if (n.Name.ToLower() != "joint")
throw new Exception();
JointType type = (JointType)Enum.Parse(typeof(JointType), n.Attributes[0].Value, true);
int bodyAIndex = -1, bodyBIndex = -1;
bool collideConnected = false;
object userData = null;
foreach (XMLFragmentElement sn in n.Elements)
{
switch (sn.Name.ToLower())
{
case "bodya":
bodyAIndex = int.Parse(sn.Value);
break;
case "bodyb":
bodyBIndex = int.Parse(sn.Value);
break;
case "collideconnected":
collideConnected = bool.Parse(sn.Value);
break;
case "userdata":
userData = ReadSimpleType(sn, null, false);
break;
}
}
PhysicsBody bodyA = _bodies[bodyAIndex];
PhysicsBody bodyB = _bodies[bodyBIndex];
switch (type)
{
case JointType.Distance:
joint = new DistanceJoint();
break;
case JointType.Friction:
joint = new FrictionJoint();
break;
case JointType.Line:
joint = new LineJoint();
break;
case JointType.Prismatic:
joint = new PrismaticJoint();
break;
case JointType.Pulley:
joint = new PulleyJoint();
break;
case JointType.Revolute:
joint = new RevoluteJoint();
break;
case JointType.Weld:
joint = new WeldJoint();
break;
case JointType.Rope:
joint = new RopeJoint();
break;
case JointType.Angle:
joint = new AngleJoint();
break;
case JointType.Slider:
joint = new SliderJoint();
break;
case JointType.Gear:
throw new Exception("GearJoint is not supported.");
default:
throw new Exception("Invalid or unsupported joint.");
}
joint.CollideConnected = collideConnected;
joint.UserData = userData;
joint.BodyA = bodyA;
joint.BodyB = bodyB;
_joints.Add(joint);
world.AddJoint(joint);
foreach (XMLFragmentElement sn in n.Elements)
{
// check for specific nodes
switch (type)
{
case JointType.Distance:
{
switch (sn.Name.ToLower())
{
case "dampingratio":
((DistanceJoint)joint).DampingRatio = float.Parse(sn.Value);
break;
case "frequencyhz":
((DistanceJoint)joint).Frequency = float.Parse(sn.Value);
break;
case "length":
((DistanceJoint)joint).Length = float.Parse(sn.Value);
break;
case "localanchora":
((DistanceJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((DistanceJoint)joint).LocalAnchorB = ReadVector(sn);
break;
}
}
break;
case JointType.Friction:
{
switch (sn.Name.ToLower())
{
case "localanchora":
((FrictionJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((FrictionJoint)joint).LocalAnchorB = ReadVector(sn);
break;
case "maxforce":
((FrictionJoint)joint).MaxForce = float.Parse(sn.Value);
break;
case "maxtorque":
((FrictionJoint)joint).MaxTorque = float.Parse(sn.Value);
break;
}
}
break;
case JointType.Line:
{
switch (sn.Name.ToLower())
{
case "enablemotor":
((LineJoint)joint).MotorEnabled = bool.Parse(sn.Value);
break;
case "localanchora":
((LineJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((LineJoint)joint).LocalAnchorB = ReadVector(sn);
break;
case "motorspeed":
((LineJoint)joint).MotorSpeed = float.Parse(sn.Value);
break;
case "dampingratio":
((LineJoint)joint).DampingRatio = float.Parse(sn.Value);
break;
case "maxmotortorque":
((LineJoint)joint).MaxMotorTorque = float.Parse(sn.Value);
break;
case "frequencyhz":
((LineJoint)joint).Frequency = float.Parse(sn.Value);
break;
case "localxaxis":
((LineJoint)joint).LocalXAxis = ReadVector(sn);
break;
}
}
break;
case JointType.Prismatic:
{
switch (sn.Name.ToLower())
{
case "enablelimit":
((PrismaticJoint)joint).LimitEnabled = bool.Parse(sn.Value);
break;
case "enablemotor":
((PrismaticJoint)joint).MotorEnabled = bool.Parse(sn.Value);
break;
case "localanchora":
((PrismaticJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((PrismaticJoint)joint).LocalAnchorB = ReadVector(sn);
break;
case "local1axis1":
((PrismaticJoint)joint).LocalXAxis1 = ReadVector(sn);
break;
case "maxmotorforce":
((PrismaticJoint)joint).MaxMotorForce = float.Parse(sn.Value);
break;
case "motorspeed":
((PrismaticJoint)joint).MotorSpeed = float.Parse(sn.Value);
break;
case "lowertranslation":
((PrismaticJoint)joint).LowerLimit = float.Parse(sn.Value);
break;
case "uppertranslation":
((PrismaticJoint)joint).UpperLimit = float.Parse(sn.Value);
break;
case "referenceangle":
((PrismaticJoint)joint).ReferenceAngle = float.Parse(sn.Value);
break;
}
}
break;
case JointType.Pulley:
{
switch (sn.Name.ToLower())
{
case "groundanchora":
((PulleyJoint)joint).GroundAnchorA = ReadVector(sn);
break;
case "groundanchorb":
((PulleyJoint)joint).GroundAnchorB = ReadVector(sn);
break;
case "lengtha":
((PulleyJoint)joint).LengthA = float.Parse(sn.Value);
break;
case "lengthb":
((PulleyJoint)joint).LengthB = float.Parse(sn.Value);
break;
case "localanchora":
((PulleyJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((PulleyJoint)joint).LocalAnchorB = ReadVector(sn);
break;
case "maxlengtha":
((PulleyJoint)joint).MaxLengthA = float.Parse(sn.Value);
break;
case "maxlengthb":
((PulleyJoint)joint).MaxLengthB = float.Parse(sn.Value);
break;
case "ratio":
((PulleyJoint)joint).Ratio = float.Parse(sn.Value);
break;
}
}
break;
case JointType.Revolute:
{
switch (sn.Name.ToLower())
{
case "enablelimit":
((RevoluteJoint)joint).LimitEnabled = bool.Parse(sn.Value);
break;
case "enablemotor":
((RevoluteJoint)joint).MotorEnabled = bool.Parse(sn.Value);
break;
case "localanchora":
((RevoluteJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((RevoluteJoint)joint).LocalAnchorB = ReadVector(sn);
break;
case "maxmotortorque":
((RevoluteJoint)joint).MaxMotorTorque = float.Parse(sn.Value);
break;
case "motorspeed":
((RevoluteJoint)joint).MotorSpeed = float.Parse(sn.Value);
break;
case "lowerangle":
((RevoluteJoint)joint).LowerLimit = float.Parse(sn.Value);
break;
case "upperangle":
((RevoluteJoint)joint).UpperLimit = float.Parse(sn.Value);
break;
case "referenceangle":
((RevoluteJoint)joint).ReferenceAngle = float.Parse(sn.Value);
break;
}
}
break;
case JointType.Weld:
{
switch (sn.Name.ToLower())
{
case "localanchora":
((WeldJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((WeldJoint)joint).LocalAnchorB = ReadVector(sn);
break;
}
}
break;
case JointType.Rope:
{
switch (sn.Name.ToLower())
{
case "localanchora":
((RopeJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((RopeJoint)joint).LocalAnchorB = ReadVector(sn);
break;
case "maxlength":
((RopeJoint)joint).MaxLength = float.Parse(sn.Value);
break;
}
}
break;
case JointType.Gear:
throw new Exception("Gear joint is unsupported");
case JointType.Angle:
{
switch (sn.Name.ToLower())
{
case "biasfactor":
((AngleJoint)joint).BiasFactor = float.Parse(sn.Value);
break;
case "maximpulse":
((AngleJoint)joint).MaxImpulse = float.Parse(sn.Value);
break;
case "softness":
((AngleJoint)joint).Softness = float.Parse(sn.Value);
break;
case "targetangle":
((AngleJoint)joint).TargetAngle = float.Parse(sn.Value);
break;
}
}
break;
case JointType.Slider:
{
switch (sn.Name.ToLower())
{
case "dampingratio":
((SliderJoint)joint).DampingRatio = float.Parse(sn.Value);
break;
case "frequencyhz":
((SliderJoint)joint).Frequency = float.Parse(sn.Value);
break;
case "maxlength":
((SliderJoint)joint).MaxLength = float.Parse(sn.Value);
break;
case "minlength":
((SliderJoint)joint).MinLength = float.Parse(sn.Value);
break;
case "localanchora":
((SliderJoint)joint).LocalAnchorA = ReadVector(sn);
break;
case "localanchorb":
((SliderJoint)joint).LocalAnchorB = ReadVector(sn);
break;
}
}
break;
}
}
}
}
}
}
private void SerializeFixture(Fixture fixture)
{
_writer.WriteStartElement("Fixture");
_writer.WriteElementString("Shape", FindShapeIndex(fixture.Shape).ToString());
_writer.WriteElementString("Density", fixture.Shape.Density.ToString());
_writer.WriteStartElement("FilterData");
_writer.WriteElementString("CategoryBits", ((int)fixture.CollisionCategories).ToString());
_writer.WriteElementString("MaskBits", ((int)fixture.CollidesWith).ToString());
_writer.WriteElementString("GroupIndex", fixture.CollisionGroup.ToString());
_writer.WriteEndElement();
_writer.WriteElementString("Friction", fixture.Friction.ToString());
_writer.WriteElementString("IsSensor", fixture.IsSensor.ToString());
_writer.WriteElementString("Restitution", fixture.Restitution.ToString());
if (fixture.UserData != null)
{
_writer.WriteStartElement("UserData");
WriteDynamicType(fixture.UserData.GetType(), fixture.UserData);
_writer.WriteEndElement();
}
_writer.WriteEndElement();
}
