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/*
* Copyright (c) Contributors, http://opensimulator.org/
* See CONTRIBUTORS.TXT for a full list of copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyrightD
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the OpenSimulator Project nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using OMV = OpenMetaverse;
namespace OpenSim.Region.PhysicsModule.BulletS
{
public class BSActorLockAxis : BSActor
{
private BSConstraint LockAxisConstraint = null;
private bool HaveRegisteredForBeforeStepCallback = false;
// The lock access flags (which axises were locked) when the contraint was built.
// Used to see if locking has changed since when the constraint was built.
OMV.Vector3 LockAxisLinearFlags;
OMV.Vector3 LockAxisAngularFlags;
public BSActorLockAxis(BSScene physicsScene, BSPhysObject pObj, string actorName)
: base(physicsScene, pObj, actorName)
{
m_physicsScene.DetailLog("{0},BSActorLockAxis,constructor", m_controllingPrim.LocalID);
LockAxisConstraint = null;
HaveRegisteredForBeforeStepCallback = false;
}
// BSActor.isActive
public override bool isActive
{
get { return Enabled && m_controllingPrim.IsPhysicallyActive; }
}
// Release any connections and resources used by the actor.
// BSActor.Dispose()
public override void Dispose()
{
Enabled = false;
UnRegisterForBeforeStepCallback();
RemoveAxisLockConstraint();
}
// Called when physical parameters (properties set in Bullet) need to be re-applied.
// Called at taint-time.
// BSActor.Refresh()
public override void Refresh()
{
// Since the axis logging is done with a constraint, Refresh() time is good for
// changing parameters but this needs to wait until the prim/linkset is physically
// constructed. Therefore, the constraint itself is placed at pre-step time.
// If all the axis are free, we don't need to exist
// Refresh() only turns off. Enabling is done by InitializeAxisActor()
// whenever parameters are changed.
// This leaves 'enable' free to turn off an actor when it is not wanted to run.
if (m_controllingPrim.LockedAngularAxis == m_controllingPrim.LockedAxisFree
&& m_controllingPrim.LockedLinearAxis == m_controllingPrim.LockedAxisFree)
{
Enabled = false;
}
if (isActive)
{
RegisterForBeforeStepCallback();
}
else
{
RemoveDependencies();
UnRegisterForBeforeStepCallback();
}
}
// The object's physical representation is being rebuilt so pick up any physical dependencies (constraints, ...).
// Register a prestep action to restore physical requirements before the next simulation step.
// Called at taint-time.
// BSActor.RemoveDependencies()
public override void RemoveDependencies()
{
RemoveAxisLockConstraint();
}
private void RegisterForBeforeStepCallback()
{
if (!HaveRegisteredForBeforeStepCallback)
{
m_physicsScene.BeforeStep += PhysicsScene_BeforeStep;
HaveRegisteredForBeforeStepCallback = true;
}
}
private void UnRegisterForBeforeStepCallback()
{
if (HaveRegisteredForBeforeStepCallback)
{
m_physicsScene.BeforeStep -= PhysicsScene_BeforeStep;
HaveRegisteredForBeforeStepCallback = false;
}
}
private void PhysicsScene_BeforeStep(float timestep)
{
// If all the axis are free, we don't need to exist
if (m_controllingPrim.LockedAngularAxis == m_controllingPrim.LockedAxisFree
&& m_controllingPrim.LockedLinearAxis == m_controllingPrim.LockedAxisFree)
{
Enabled = false;
}
// If the object is physically active, add the axis locking constraint
if (isActive)
{
// Check to see if the locking parameters have changed
if (m_controllingPrim.LockedLinearAxis != this.LockAxisLinearFlags
|| m_controllingPrim.LockedAngularAxis != this.LockAxisAngularFlags)
{
// The locking has changed. Remove the old constraint and build a new one
RemoveAxisLockConstraint();
}
AddAxisLockConstraint();
}
else
{
RemoveAxisLockConstraint();
}
}
// Note that this relies on being called at TaintTime
private void AddAxisLockConstraint()
{
if (LockAxisConstraint == null)
{
// Lock that axis by creating a 6DOF constraint that has one end in the world and
// the other in the object.
// http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?p=20817
// http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?p=26380
// Remove any existing axis constraint (just to be sure)
RemoveAxisLockConstraint();
BSConstraint6Dof axisConstrainer = new BSConstraint6Dof(m_physicsScene.World, m_controllingPrim.PhysBody,
OMV.Vector3.Zero, OMV.Quaternion.Identity,
false /* useLinearReferenceFrameB */, true /* disableCollisionsBetweenLinkedBodies */);
LockAxisConstraint = axisConstrainer;
m_physicsScene.Constraints.AddConstraint(LockAxisConstraint);
// Remember the clocking being inforced so we can notice if they have changed
LockAxisLinearFlags = m_controllingPrim.LockedLinearAxis;
LockAxisAngularFlags = m_controllingPrim.LockedAngularAxis;
// The constraint is tied to the world and oriented to the prim.
if (!axisConstrainer.SetLinearLimits(m_controllingPrim.LockedLinearAxisLow, m_controllingPrim.LockedLinearAxisHigh))
{
m_physicsScene.DetailLog("{0},BSActorLockAxis.AddAxisLockConstraint,failedSetLinearLimits",
m_controllingPrim.LocalID);
}
if (!axisConstrainer.SetAngularLimits(m_controllingPrim.LockedAngularAxisLow, m_controllingPrim.LockedAngularAxisHigh))
{
m_physicsScene.DetailLog("{0},BSActorLockAxis.AddAxisLockConstraint,failedSetAngularLimits",
m_controllingPrim.LocalID);
}
m_physicsScene.DetailLog("{0},BSActorLockAxis.AddAxisLockConstraint,create,linLow={1},linHi={2},angLow={3},angHi={4}",
m_controllingPrim.LocalID,
m_controllingPrim.LockedLinearAxisLow,
m_controllingPrim.LockedLinearAxisHigh,
m_controllingPrim.LockedAngularAxisLow,
m_controllingPrim.LockedAngularAxisHigh);
// Constants from one of the posts mentioned above and used in Bullet's ConstraintDemo.
axisConstrainer.TranslationalLimitMotor(true /* enable */, 5.0f, 0.1f);
axisConstrainer.RecomputeConstraintVariables(m_controllingPrim.RawMass);
RegisterForBeforeStepCallback();
}
}
private void RemoveAxisLockConstraint()
{
UnRegisterForBeforeStepCallback();
if (LockAxisConstraint != null)
{
m_physicsScene.Constraints.RemoveAndDestroyConstraint(LockAxisConstraint);
LockAxisConstraint = null;
m_physicsScene.DetailLog("{0},BSActorLockAxis.RemoveAxisLockConstraint,destroyingConstraint", m_controllingPrim.LocalID);
}
}
}
}
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