void OnMouseMove(object sender, MouseEventArgs args)
{
switch (_dragMode)
{
case DragMode.None:
var hit = HitTest(_graph.Window, args.Location);
switch (hit)
{
case HitKind.None:
_graph.Control.Cursor = Cursors.Default;
_dragMode = DragMode.None;
_hypotheticalDragMode = DragMode.None;
_dragStart = null;
break;
case HitKind.LeftEdge:
_graph.Control.Cursor = Cursors.SizeWE;
_hypotheticalDragMode = DragMode.ResizeLeft;
break;
case HitKind.RightEdge:
_graph.Control.Cursor = Cursors.SizeWE;
_hypotheticalDragMode = DragMode.ResizeRight;
break;
case HitKind.Center:
_graph.Control.Cursor = Hand;
_hypotheticalDragMode = DragMode.Center;
break;
}
break;
case DragMode.ResizeLeft:
ResizeLeft(_graph.Window, _dragStart.Value, args.Location);
_dragStart = args.Location;
_graph.Draw();
break;
case DragMode.ResizeRight:
ResizeRight(_graph.Window, _dragStart.Value, args.Location);
_dragStart = args.Location;
_graph.Draw();
break;
case DragMode.Center:
Drag(_graph.Window, _dragStart.Value, args.Location);
_dragStart = args.Location;
_graph.Draw();
break;
default:
throw new ArgumentOutOfRangeException();
}
}