/// <summary>
 /// Occurs when the mouse moves over the CanvasPane.
 /// Update the CurrentMouseCell in UISettings with the mouse position, and calls the Rulers to update.
 /// </summary>
 /// <param name="sender"></param>
 /// <param name="e"></param>
 private void CanvasPane_MouseMove(object sender, MouseEventArgs e)
 {
     _global.UI.MousePosition = _global.CalcLatticePoint(new Point(e.X, e.Y));
     if (_global.CurrentTool != null)
     {
         _global.CurrentTool.Tool.MouseMove(e.Button, _global.UI.MousePosition, e.Location);
     }
     RefreshRulers();
 }