void frame_MouseOver(Element sender, MouseEventArgs e) { var pcur = new Vector2(e.CurrentMouseState.X, e.CurrentMouseState.Y); var pold = new Vector2(e.PreviousMouseState.X, e.PreviousMouseState.Y); if (mactive) { PE.AddInstantaneousForceField(new InstantaneousForceField(pcur, rad, DefaultForces.GenerateDirectionalField(400 * (pcur - pold), rad))); } }