public override bool SliderMotorEnable(BulletConstraint pConstraint, int linAng, float numericTrueFalse)
     {
         SliderConstraint constraint = (pConstraint as BulletConstraintXNA).constrain as SliderConstraint;
 		switch (linAng)
 		{
 			case SLIDER_LINEAR:
 				constraint.SetPoweredLinMotor(numericTrueFalse == 0.0 ? false : true);
 				break;
 			case SLIDER_ANGULAR:
 				constraint.SetPoweredAngMotor(numericTrueFalse == 0.0 ? false : true);
 				break;
 		}
         return true;
     }

 public abstract bool SpringSetEquilibriumPoint(BulletConstraint constrain, int index, float equilibriumPoint);

 public abstract bool TranslationalLimitMotor(BulletConstraint constrain, float enable, float targetVel,
     float maxMotorForce);

 public abstract bool SliderSet(BulletConstraint constrain, int softRestDamp, int dirLimOrtho, int linAng, float val);

 public abstract bool SpringEnable(BulletConstraint constrain, int index, float numericTrueFalse);

 public abstract bool SetFrames(BulletConstraint constrain,
     Vector3 frameA, Quaternion frameArot, Vector3 frameB, Quaternion frameBrot);

 public abstract bool SliderMotor(BulletConstraint constrain, int forceVel, int linAng, float val);

 public virtual void DumpConstraint(BulletWorld sim, BulletConstraint constrain)
 {
 }

 // =====================================================================================
 // btCollisionObject entries
 public abstract Vector3 GetAnisotripicFriction(BulletConstraint constrain);

 public abstract bool CalculateTransforms(BulletConstraint constrain);

 public abstract bool DestroyConstraint(BulletWorld world, BulletConstraint constrain);

 public abstract bool AddConstraintToWorld(BulletWorld world, BulletConstraint constrain,
     bool disableCollisionsBetweenLinkedObjects);

 public abstract void AddConstraintRef(BulletBody obj, BulletConstraint constrain);

     public override bool SliderMotor(BulletConstraint pConstraint, int forceVel, int linAng, float val)
     {
         SliderConstraint constraint = (pConstraint as BulletConstraintXNA).constrain as SliderConstraint;
 		switch (forceVel)
 		{
 			case SLIDER_MOTOR_VELOCITY:
 				switch (linAng)
 				{
 					case SLIDER_LINEAR:
 						constraint.SetTargetLinMotorVelocity(val);
 						break;
 					case SLIDER_ANGULAR:
 						constraint.SetTargetAngMotorVelocity(val);
 						break;
 				}
 				break;
 			case SLIDER_MAX_MOTOR_FORCE:
 				switch (linAng)
 				{
 					case SLIDER_LINEAR:
 						constraint.SetMaxLinMotorForce(val);
 						break;
 					case SLIDER_ANGULAR:
 						constraint.SetMaxAngMotorForce(val);
 						break;
 				}
 				break;
 		}
         return true;
     }

 public abstract void SetConstraintNumSolverIterations(BulletConstraint constrain, float iterations);

 public abstract bool HasAnisotripicFriction(BulletConstraint constrain);

 public abstract bool SetConstraintParam(BulletConstraint constrain, ConstraintParams paramIndex, float value,
     ConstraintParamAxis axis);

 public abstract bool HingeSetLimits(BulletConstraint constrain, float low, float high, float softness, float bias, float relaxation);

 public abstract bool SetLinearLimits(BulletConstraint constrain, Vector3 low, Vector3 hi);

 public abstract bool RemoveConstraintFromWorld(BulletWorld world, BulletConstraint constrain);