I decided to go ahead and introduce the Main Menu on application's area. It's going to be a tricky one since everything is tricky in case of multi-touch applications. This one can be in a few states:
1. 2. 3. 4. 5.
1. idle (semitransparent)
2. "on-touch-over" (highlighted) - e.g. when some blob moved from outside
3. "on-touch-press" (highlighted and expanded) - new blob has been created within the button area
4. "on-touch-out" (expanded but not highlighted) - blob goes off the button or dies - after 3. took place
5. "on-touch-press" of first option ("Create a new rectangle"):
On state 5. - the other hand can draw a shape of rectangle which becomes a rectangular object in world of "physics". When 5. is released - the main menu goes to the state 1.
Tweener (caurina) is used for menu visual effects.