It's always treated as a down event. By default our tools support a drag operation by just having _OnDataButton called from _OnModelEndDrag. This way the exact same logic can be used for example to create a line by down->drag->up as click, click.
If you want to distinguish between the two, you can override _OnModelEndDrag. HTH
-B
If you want to distinguish between the two, you can override _OnModelEndDrag. HTH
-B