Sprite trim

[monoloco]

Hi there,

 

I'm trying to make some kind of a worm bit on my map, the problem is that the map is not a tile map, it's a sprite and has p2 physics on it so that I can use it as a sensor.

 

I've been trying to make a bitmapData onto which I copy a circle of the background and overlap it to the map, but it does not work.

 

Any idea is much appreciated.