private void SerializeJoint(FarseerJoint joint)
{
if (joint.IsFixedType())
return;
_writer.WriteStartElement("Joint");
_writer.WriteAttributeString("Type", joint.JointType.ToString());
WriteElement("BodyA", FindBodyIndex(joint.BodyA));
WriteElement("BodyB", FindBodyIndex(joint.BodyB));
WriteElement("CollideConnected", joint.CollideConnected);
WriteElement("Breakpoint", joint.Breakpoint);
if (joint.UserData != null)
{
_writer.WriteStartElement("UserData");
WriteDynamicType(joint.UserData.GetType(), joint.UserData);
_writer.WriteEndElement();
}
switch (joint.JointType)
{
case JointType.Distance:
{
DistanceJoint djd = (DistanceJoint)joint;
WriteElement("DampingRatio", djd.DampingRatio);
WriteElement("FrequencyHz", djd.Frequency);
WriteElement("Length", djd.Length);
WriteElement("LocalAnchorA", djd.LocalAnchorA);
WriteElement("LocalAnchorB", djd.LocalAnchorB);
}
break;
case JointType.Friction:
{
FrictionJoint fjd = (FrictionJoint)joint;
WriteElement("LocalAnchorA", fjd.LocalAnchorA);
WriteElement("LocalAnchorB", fjd.LocalAnchorB);
WriteElement("MaxForce", fjd.MaxForce);
WriteElement("MaxTorque", fjd.MaxTorque);
}
break;
case JointType.Gear:
throw new Exception("Gear joint not supported by serialization");
//case JointType.Wheel:
// {
// WheelJoint ljd = (WheelJoint)joint;
// WriteElement("EnableMotor", ljd.MotorEnabled);
// WriteElement("LocalAnchorA", ljd.LocalAnchorA);
// WriteElement("LocalAnchorB", ljd.LocalAnchorB);
// WriteElement("MotorSpeed", ljd.MotorSpeed);
// WriteElement("DampingRatio", ljd.DampingRatio);
// WriteElement("MaxMotorTorque", ljd.MaxMotorTorque);
// WriteElement("FrequencyHz", ljd.Frequency);
// WriteElement("LocalXAxis", ljd.LocalXAxis);
// }
// break;
case JointType.Prismatic:
{
PrismaticJoint pjd = (PrismaticJoint)joint;
//NOTE: Does not conform with Box2DScene
WriteElement("EnableLimit", pjd.LimitEnabled);
WriteElement("EnableMotor", pjd.MotorEnabled);
WriteElement("LocalAnchorA", pjd.LocalAnchorA);
WriteElement("LocalAnchorB", pjd.LocalAnchorB);
WriteElement("LocalXAxis1", pjd.LocalXAxisA);
WriteElement("LowerTranslation", pjd.LowerLimit);
WriteElement("UpperTranslation", pjd.UpperLimit);
WriteElement("MaxMotorForce", pjd.MaxMotorForce);
WriteElement("MotorSpeed", pjd.MotorSpeed);
}
break;
//case JointType.Pulley:
// {
// PulleyJoint pjd = (PulleyJoint)joint;
// WriteElement("GroundAnchorA", pjd.GroundAnchorA);
// WriteElement("GroundAnchorB", pjd.GroundAnchorB);
// WriteElement("LengthA", pjd.LengthA);
// WriteElement("LengthB", pjd.LengthB);
// WriteElement("LocalAnchorA", pjd.LocalAnchorA);
// WriteElement("LocalAnchorB", pjd.LocalAnchorB);
// WriteElement("MaxLengthA", pjd.MaxLengthA);
// WriteElement("MaxLengthB", pjd.MaxLengthB);
// WriteElement("Ratio", pjd.Ratio);
// }
// break;
case JointType.Revolute:
{
RevoluteJoint rjd = (RevoluteJoint)joint;
WriteElement("EnableLimit", rjd.LimitEnabled);
WriteElement("EnableMotor", rjd.MotorEnabled);
WriteElement("LocalAnchorA", rjd.LocalAnchorA);
WriteElement("LocalAnchorB", rjd.LocalAnchorB);
WriteElement("LowerAngle", rjd.LowerLimit);
WriteElement("MaxMotorTorque", rjd.MaxMotorTorque);
WriteElement("MotorSpeed", rjd.MotorSpeed);
WriteElement("ReferenceAngle", rjd.ReferenceAngle);
WriteElement("UpperAngle", rjd.UpperLimit);
}
break;
case JointType.Weld:
{
WeldJoint wjd = (WeldJoint)joint;
WriteElement("LocalAnchorA", wjd.LocalAnchorA);
WriteElement("LocalAnchorB", wjd.LocalAnchorB);
}
break;
//
// Not part of Box2DScene
//
case JointType.Rope:
{
RopeJoint rjd = (RopeJoint)joint;
WriteElement("LocalAnchorA", rjd.LocalAnchorA);
WriteElement("LocalAnchorB", rjd.LocalAnchorB);
WriteElement("MaxLength", rjd.MaxLength);
}
break;
case JointType.Angle:
{
AngleJoint aj = (AngleJoint)joint;
WriteElement("BiasFactor", aj.BiasFactor);
WriteElement("MaxImpulse", aj.MaxImpulse);
WriteElement("Softness", aj.Softness);
WriteElement("TargetAngle", aj.TargetAngle);
}
break;
case JointType.Slider:
{
SliderJoint sliderJoint = (SliderJoint)joint;
WriteElement("DampingRatio", sliderJoint.DampingRatio);
WriteElement("FrequencyHz", sliderJoint.Frequency);
WriteElement("MaxLength", sliderJoint.MaxLength);
WriteElement("MinLength", sliderJoint.MinLength);
WriteElement("LocalAnchorA", sliderJoint.LocalAnchorA);
WriteElement("LocalAnchorB", sliderJoint.LocalAnchorB);
}
break;
default:
throw new Exception("Joint not supported");
}
_writer.WriteEndElement();
}
/// <summary>
/// Destroy a joint. This may cause the connected bodies to begin colliding.
/// </summary>
/// <param name="joint">The joint.</param>
public void RemoveJoint(FarseerJoint joint)
{
RemoveJoint(joint, true);
}
public static FSGearJoint CreateGearJoint(FSWorld world, FarseerJoint jointA, FarseerJoint jointB, float ratio)
{
FSGearJoint gearJoint = new FSGearJoint(jointA, jointB, ratio);
world.AddJoint(gearJoint);
return gearJoint;
}
private void RemoveJoint(FarseerJoint joint, bool doCheck)
{
if (doCheck)
{
Debug.Assert(!_jointRemoveList.Contains(joint),
"The joint is already marked for removal. You are removing the joint more than once.");
}
if (!_jointRemoveList.Contains(joint))
_jointRemoveList.Add(joint);
}
/// <summary>
/// Create a joint to constrain bodies together. This may cause the connected bodies to cease colliding.
/// </summary>
/// <param name="joint">The joint.</param>
public void AddJoint(FarseerJoint joint)
{
Debug.Assert(!_jointAddList.Contains(joint), "You are adding the same joint more than once.");
if (!_jointAddList.Contains(joint))
_jointAddList.Add(joint);
}
public void Add(FarseerJoint joint)
{
Debug.Assert(JointCount < JointCapacity);
_joints[JointCount++] = joint;
}
/// <summary>
/// Requires two existing revolute or prismatic joints (any combination will work).
/// The provided joints must attach a dynamic body to a static body.
/// </summary>
/// <param name="jointA">The first joint.</param>
/// <param name="jointB">The second joint.</param>
/// <param name="ratio">The ratio.</param>
public GearJoint(FarseerJoint jointA, FarseerJoint jointB, float ratio)
: base(jointA.BodyA, jointA.BodyB)
{
JointType = JointType.Gear;
JointA = jointA;
JointB = jointB;
Ratio = ratio;
m_typeA = jointA.JointType;
m_typeB = jointB.JointType;
// Make sure its the right kind of joint
Debug.Assert(m_typeA == JointType.Revolute || m_typeA == JointType.Prismatic || m_typeA == JointType.FixedRevolute || m_typeA == JointType.FixedPrismatic);
Debug.Assert(m_typeB == JointType.Revolute || m_typeB == JointType.Prismatic || m_typeB == JointType.FixedRevolute || m_typeB == JointType.FixedPrismatic);
float coordinateA = 0.0f, coordinateB = 0.0f;
m_bodyC = JointA.BodyA;
BodyA = JointA.BodyB;
// Get geometry of joint1
Transform xfA = BodyA.Xf;
float aA = BodyA.Sweep.A;
Transform xfC = m_bodyC.Xf;
float aC = m_bodyC.Sweep.A;
if (m_typeA == JointType.Revolute)
{
RevoluteJoint revolute = (RevoluteJoint)jointA;
m_localAnchorC = revolute.LocalAnchorA;
m_localAnchorA = revolute.LocalAnchorB;
m_referenceAngleA = revolute.ReferenceAngle;
m_localAxisC = FVector2.Zero;
coordinateA = aA - aC - m_referenceAngleA;
}
else
{
PrismaticJoint prismatic = (PrismaticJoint)jointA;
m_localAnchorC = prismatic.LocalAnchorA;
m_localAnchorA = prismatic.LocalAnchorB;
m_referenceAngleA = prismatic.ReferenceAngle;
m_localAxisC = prismatic.LocalXAxisA;
FVector2 pC = m_localAnchorC;
FVector2 pA = MathUtils.MulT(xfC.q, MathUtils.Mul(xfA.q, m_localAnchorA) + (xfA.p - xfC.p));
coordinateA = FVector2.Dot(pA - pC, m_localAxisC);
}
m_bodyD = JointB.BodyA;
BodyB = JointB.BodyB;
// Get geometry of joint2
Transform xfB = BodyB.Xf;
float aB = BodyB.Sweep.A;
Transform xfD = m_bodyD.Xf;
float aD = m_bodyD.Sweep.A;
if (m_typeB == JointType.Revolute)
{
RevoluteJoint revolute = (RevoluteJoint)jointB;
m_localAnchorD = revolute.LocalAnchorA;
m_localAnchorB = revolute.LocalAnchorB;
m_referenceAngleB = revolute.ReferenceAngle;
m_localAxisD = FVector2.Zero;
coordinateB = aB - aD - m_referenceAngleB;
}
else
{
PrismaticJoint prismatic = (PrismaticJoint)jointB;
m_localAnchorD = prismatic.LocalAnchorA;
m_localAnchorB = prismatic.LocalAnchorB;
m_referenceAngleB = prismatic.ReferenceAngle;
m_localAxisD = prismatic.LocalXAxisA;
FVector2 pD = m_localAnchorD;
FVector2 pB = MathUtils.MulT(xfD.q, MathUtils.Mul(xfB.q, m_localAnchorB) + (xfB.p - xfD.p));
coordinateB = FVector2.Dot(pB - pD, m_localAxisD);
}
_ratio = ratio;
m_constant = coordinateA + _ratio * coordinateB;
}
/// <summary>
/// Requires two existing revolute or prismatic joints (any combination will work).
/// The provided joints must attach a dynamic body to a static body.
/// </summary>
/// <param name="jointA">The first joint.</param>
/// <param name="jointB">The second joint.</param>
/// <param name="ratio">The ratio.</param>
public GearJoint(FarseerJoint jointA, FarseerJoint jointB, float ratio)
: base(jointA.BodyA, jointA.BodyB)
{
JointType = JointType.Gear;
JointA = jointA;
JointB = jointB;
Ratio = ratio;
m_typeA = jointA.JointType;
m_typeB = jointB.JointType;
// Make sure its the right kind of joint
Debug.Assert(m_typeA == JointType.Revolute || m_typeA == JointType.Prismatic || m_typeA == JointType.FixedRevolute || m_typeA == JointType.FixedPrismatic);
Debug.Assert(m_typeB == JointType.Revolute || m_typeB == JointType.Prismatic || m_typeB == JointType.FixedRevolute || m_typeB == JointType.FixedPrismatic);
float coordinateA = 0.0f, coordinateB = 0.0f;
m_bodyC = JointA.BodyA;
BodyA = JointA.BodyB;
// Get geometry of joint1
Transform xfA = BodyA.Xf;
float aA = BodyA.Sweep.A;
Transform xfC = m_bodyC.Xf;
float aC = m_bodyC.Sweep.A;
if (m_typeA == JointType.Revolute)
{
RevoluteJoint revolute = (RevoluteJoint)jointA;
m_localAnchorC = revolute.LocalAnchorA;
m_localAnchorA = revolute.LocalAnchorB;
m_referenceAngleA = revolute.ReferenceAngle;
m_localAxisC = FVector2.Zero;
coordinateA = aA - aC - m_referenceAngleA;
}
else
{
PrismaticJoint prismatic = (PrismaticJoint)jointA;
m_localAnchorC = prismatic.LocalAnchorA;
m_localAnchorA = prismatic.LocalAnchorB;
m_referenceAngleA = prismatic.ReferenceAngle;
m_localAxisC = prismatic.LocalXAxisA;
FVector2 pC = m_localAnchorC;
FVector2 pA = MathUtils.MulT(xfC.q, MathUtils.Mul(xfA.q, m_localAnchorA) + (xfA.p - xfC.p));
coordinateA = FVector2.Dot(pA - pC, m_localAxisC);
}
m_bodyD = JointB.BodyA;
BodyB = JointB.BodyB;
// Get geometry of joint2
Transform xfB = BodyB.Xf;
float aB = BodyB.Sweep.A;
Transform xfD = m_bodyD.Xf;
float aD = m_bodyD.Sweep.A;
if (m_typeB == JointType.Revolute)
{
RevoluteJoint revolute = (RevoluteJoint)jointB;
m_localAnchorD = revolute.LocalAnchorA;
m_localAnchorB = revolute.LocalAnchorB;
m_referenceAngleB = revolute.ReferenceAngle;
m_localAxisD = FVector2.Zero;
coordinateB = aB - aD - m_referenceAngleB;
}
else
{
PrismaticJoint prismatic = (PrismaticJoint)jointB;
m_localAnchorD = prismatic.LocalAnchorA;
m_localAnchorB = prismatic.LocalAnchorB;
m_referenceAngleB = prismatic.ReferenceAngle;
m_localAxisD = prismatic.LocalXAxisA;
FVector2 pD = m_localAnchorD;
FVector2 pB = MathUtils.MulT(xfD.q, MathUtils.Mul(xfB.q, m_localAnchorB) + (xfB.p - xfD.p));
coordinateB = FVector2.Dot(pB - pD, m_localAxisD);
}
_ratio = ratio;
m_constant = coordinateA + _ratio * coordinateB;
}
