Yeah, I was having trouble getting the volume to work how I wanted it to. I wanted it to fade away quickly, and not have a harsh on/off effect, but I just couldn't get it working right. Still messing with it.
I can't take full credit for the mouse gestures because cow_trix suggested a system in the help thread. I tried it and it worked and I added in a few extra checks to make sure a circle was drawn exactly.
It's really simple.
Basically, a group of invisible sprites follow the mouse cursor, that look like that diagram. When the mouse button is held down, the group sets into position and will no longer move where the cursor goes. When the mouse button is released the group pops back into position following the cursor.
The little sprites in a circle path can be turned on if the mouse cursor touches them. They will turn off if they touch any of the blue sprites. When all the waypoint sprites are turned on it initiates an event. The player MUST draw some semblance of a circle in order for all the waypoint sprites to be turned on at the same time. See easy?
So now, theoretically, I could make a square or a triangle or any other shape I want with this same premise. Or I could even have smaller circles cause different events.
Something I thought about implementing (but didn't do) was to try scaling. So that the size of the invisible sprite group would change according to how far the mouse is moved, so that a circle could be drawn at any size, so long as it was a circle. It was about 2 or 3 events too much work for me, though. haha. It could be done like that too though.