I think a question of something similar has been asked and answered, but mine is different:
So, say I want the system to perform an action when a circle is drawn on the screen, in the middle. I want to be able to draw a circle on the screen, then, as soon as you stop drawing it, the system would read the canvas and say "well hey that's a circle" and associate that with a certain action.
Basically, I want to have the system associate different hand-drawn symbols with pre-programmed symbols, and perform an action after the user-friendly symbol is associated with the system's symbol in its memory.
Can I do this in a practical way, and if so, how would I go about doing this?