protected internal void jointMoved(PhysicsJoint joint)
{
// m_parentScene.PhysicsScene.DumpJointInfo(); // non-thread-locked version; we should already be in a lock (OdeLock) when this callback is invoked
SceneObjectPart jointProxyObject = GetSceneObjectPart(joint.ObjectNameInScene);
if (jointProxyObject == null)
{
jointErrorMessage(joint, "WARNING, joint proxy not found, name " + joint.ObjectNameInScene);
return;
}
// now update the joint proxy object in the scene to have the position of the joint as returned by the physics engine
SceneObjectPart trackedBody = GetSceneObjectPart(joint.TrackedBodyName); // FIXME: causes a sequential lookup
if (trackedBody == null) return; // the actor may have been deleted but the joint still lingers around a few frames waiting for deletion. during this time, trackedBody is NULL to prevent further motion of the joint proxy.
jointProxyObject.Velocity = trackedBody.Velocity;
jointProxyObject.AngularVelocity = trackedBody.AngularVelocity;
switch (joint.Type)
{
case PhysicsJointType.Ball:
{
Vector3 jointAnchor = PhysicsScene.GetJointAnchor(joint);
Vector3 proxyPos = new Vector3(jointAnchor.X, jointAnchor.Y, jointAnchor.Z);
jointProxyObject.ParentGroup.UpdateGroupPosition(proxyPos); // schedules the entire group for a terse update
}
break;
case PhysicsJointType.Hinge:
{
Vector3 jointAnchor = PhysicsScene.GetJointAnchor(joint);
// Normally, we would just ask the physics scene to return the axis for the joint.
// Unfortunately, ODE sometimes returns <0,0,0> for the joint axis, which should
// never occur. Therefore we cannot rely on ODE to always return a correct joint axis.
// Therefore the following call does not always work:
//PhysicsVector phyJointAxis = _PhyScene.GetJointAxis(joint);
// instead we compute the joint orientation by saving the original joint orientation
// relative to one of the jointed bodies, and applying this transformation
// to the current position of the jointed bodies (the tracked body) to compute the
// current joint orientation.
if (joint.TrackedBodyName == null)
{
jointErrorMessage(joint, "joint.TrackedBodyName is null, joint " + joint.ObjectNameInScene);
}
Vector3 proxyPos = new Vector3(jointAnchor.X, jointAnchor.Y, jointAnchor.Z);
Quaternion q = trackedBody.RotationOffset * joint.LocalRotation;
jointProxyObject.ParentGroup.UpdateGroupPosition(proxyPos); // schedules the entire group for a terse update
jointProxyObject.ParentGroup.UpdateGroupRotationR(q); // schedules the entire group for a terse update
}
break;
}
}
