private void DoPIDMoveTarget(float timeStep, uint frameNum)
{
float tau;
OpenMetaverse.Vector3 target;
float gtau;
lock (_properties)
{
tau = _properties.MoveTargetTau;
target = _properties.MoveTarget;
gtau = _properties.GrabTargetTau;
}
// Grab overrides move to target
if (gtau != 0)
{
return;
}
if (tau > MIN_TAU)
{
//i had a whole elaborate setup here to do this.. turns out the linden
//implementation was much simpler
OpenMetaverse.Vector3 distance = target - _position;
if (distance.LengthSquared() <= AT_TARGET_TOLERANCE_SQUARED)
{
if (_velocity != OpenMetaverse.Vector3.Zero)
{
StopLinearMovement();
return;
}
}
ChangeGravityIfNeeded();
_dynActor.AddForce(PhysUtil.OmvVectorToPhysx((distance * (1.0f / tau)) - _velocity), PhysX.ForceMode.VelocityChange, true);
}
else // Check for stop move to target - need to turn gravity back on if buoyancy isn't enabled
if ((target == OpenMetaverse.Vector3.Zero) && (tau == 0.0f))
{
ChangeGravityIfNeeded();
}
}
private bool DoGrabTarget(float timeStep, uint frameNum)
{
float tau;
OpenMetaverse.Vector3 target;
lock (_properties)
{
tau = _properties.GrabTargetTau;
target = _properties.GrabTarget;
}
if (tau > MIN_TAU)
{
_dynActor.AddTorque(PhysUtil.OmvVectorToPhysx(-_angularVelocity * 0.9f), PhysX.ForceMode.VelocityChange, false);
OpenMetaverse.Vector3 distance = target - _position;
if (distance.LengthSquared() <= AT_TARGET_TOLERANCE_SQUARED)
{
if (_velocity != OpenMetaverse.Vector3.Zero)
{
StopLinearMovement();
return(true);
}
}
_grabDisableGravity = true;
ChangeGravityIfNeeded();
_dynActor.AddForce(PhysUtil.OmvVectorToPhysx((distance * (1.0f / tau)) - _velocity), PhysX.ForceMode.VelocityChange, true);
}
else
{
// Check for stop move to grab - need to turn gravity back on if buoyancy isn't enabled
if (tau == 0.0f)
{
_grabDisableGravity = false;
ChangeGravityIfNeeded();
return(false);
}
}
return(true);
}
private void DecayForces(float secondsSinceLastSync)
{
if (_vForces != OpenMetaverse.Vector3.Zero)
{
if (_vTarget != OpenMetaverse.Vector3.Zero)
{
if (!_flying)
{
//user movement instantly cancels any x or y axis movement, but
//it does not cancel z axis movement while jumping. This allows the user to have
//a nice jump while walking
_vForces.X = 0f;
_vForces.Y = 0f;
}
else
{
_vForces = OpenMetaverse.Vector3.Zero;
}
}
else
{
//decay velocity in relation to velocity to badly mimic drag
OpenMetaverse.Vector3 decayForce;
if (_collidingGround)
{
decayForce = OpenMetaverse.Vector3.Multiply(_vForces, 2.0f * secondsSinceLastSync);
}
else
{
decayForce = OpenMetaverse.Vector3.Multiply(_vForces, 1.0f * secondsSinceLastSync);
}
_vForces -= decayForce;
if (_vForces.LengthSquared() < MIN_FORCE_MAG_BEFORE_ZEROING_SQUARED)
{
_vForces = OpenMetaverse.Vector3.Zero;
}
}
}
}
