Universe.Physics.BulletSPlugin.BSDynamics.ComputeLinearMotorUp C# (CSharp) Method

        public void ComputeLinearMotorUp(float pTimestep)
        {
            if ((m_flags & (VehicleFlag.LIMIT_MOTOR_UP)) != 0)
            {
                // This code tries to decide if the object is not on the ground and then pushing down
                /*
                float targetHeight = Type == Vehicle.TYPE_BOAT ? GetWaterLevel(VehiclePosition) : GetTerrainHeight(VehiclePosition);
                distanceAboveGround = VehiclePosition.Z - targetHeight;
                // Not colliding if the vehicle is off the ground
                if (!Prim.IsColliding)
                {
                    // downForce = new Vector3(0, 0, -distanceAboveGround / m_bankingTimescale);
                    VehicleVelocity += new Vector3(0, 0, -distanceAboveGround);
                }
                // TODO: this calculation is wrong. From the description at
                //     (http://wiki.secondlife.com/wiki/Category:LSL_Vehicle), the downForce
                //     has a decay factor. This says this force should
                //     be computed with a motor.
                // TODO: add interaction with banking.
                VDetailLog("{0},  MoveLinear,limitMotorUp,distAbove={1},colliding={2},ret={3}",
                                Prim.LocalID, distanceAboveGround, Prim.IsColliding, ret);
                 */

                // Another approach is to measure if we're going up. If going up and not colliding,
                //     the vehicle is in the air.  Fix that by pushing down.
                if (!ControllingPrim.IsColliding && VehicleVelocity.Z > 0.1)
                {
                    // Get rid of any of the velocity vector that is pushing us up.
                    float upVelocity = VehicleVelocity.Z;
                    VehicleVelocity += new Vector3(0, 0, -upVelocity);

                    /*
                    // If we're pointed up into the air, we should nose down
                    Vector3 pointingDirection = Vector3.UnitX * VehicleOrientation;
                    // The rotation around the Y axis is pitch up or down
                    if (pointingDirection.Y > 0.01f)
                    {
                        float angularCorrectionForce = -(float)Math.Asin(pointingDirection.Y);
                        Vector3 angularCorrectionVector = new Vector3(0f, angularCorrectionForce, 0f);
                        // Rotate into world coordinates and apply to vehicle
                        angularCorrectionVector *= VehicleOrientation;
                        VehicleAddAngularForce(angularCorrectionVector);
                        VDetailLog("{0},  MoveLinear,limitMotorUp,newVel={1},pntDir={2},corrFrc={3},aCorr={4}",
                                    Prim.LocalID, VehicleVelocity, pointingDirection, angularCorrectionForce, angularCorrectionVector);
                    }
                        */
                    VDetailLog("{0},  MoveLinear,limitMotorUp,collide={1},upVel={2},newVel={3}",
                        ControllingPrim.LocalID, ControllingPrim.IsColliding, upVelocity, VehicleVelocity);
                }
            }
        }