[Etoys] Jiggling the mouse

[K. K. Subramaniam]

On Friday 01 Aug 2008 4:23:49 am Scott Wallace wrote:
> Therefore, when a child wanted to drag a Sketch, just moving the mouse
> pointer over it brought up a halo, and that halo always included the
> "center of rotation" handle, typically right at the center of Sketch,
> right where the child was likely to grab it if intending to "pick it
> up."
mouse over halos are useful when the pointer has a single button only (e.g. 
handhelds with touch stylus.

Pick-on-click changes the z-order and I have seen children getting flustered 
when many minutes of careful stacking gets changed by a casual click. 
Treating click-drag as a move may be a better option.

How about the following for handling mouse events?

   if mouse-over-halos is true then
	on hover bring up halo. bring up direction handles based on pref
   if bluebutton is pressed
	bring up halo with direction handles always.
and then
   if halo is on
	ignore mouse clicks outside of halo buttons and dir handles.
        allow dir handle to be moved/rotated using direct drag.
   else
	allow morph to be moved using direct drag.

> Nowadays, however, we operate with mouse-over-halos turned off, and
> with the showDirectionForSketches preference turned off as well.
If direction handles are always shown, kids learn to anticipate its 
appearance. I introduce it to them as "legs" (arrow is the big toe) around 
which the morph can turn or leave a trail. This metaphor goes well with the 
overall theme of costumes and players.

Subbu