Ok, I got mirroring working. Here's an example.

Starting with moving the mouse over this corner:



If you click down and start to drag, a little target marker will appear on the opposite side of the shape, shown with the red arrow here:



If you move your mouse over to that opposite side point, it will snap on and do a mirror just as if you had run the mirror command along the edge of the object's bounding box:



So it will be possible to do simple scaling, rotation, and now also mirroring by using the frame grips instead of firing up the full transform commands for those.




Also I've set it up so that holding down shift will do a 2D transform on a 3D volume object, so you can hold down shift and drag on a sphere in the Top view to scale it in x and y but leave z as it is, same as the Scale2D command.


- Michael