protected override void MouseUp(MapDocument document, MapViewport viewport, PerspectiveCamera camera, ViewportEvent e) { if (viewport != ActiveViewport) { return; } if (_mouseDown != CircleType.None && _mouseMovePoint != null) { e.Handled = true; } var transformation = GetTransformationMatrix(viewport); OnTransformed(transformation); _mouseDown = CircleType.None; _mouseMovePoint = null; viewport.ReleaseInputLock(this); }