title: sprite kit collisions: ignore transparency?
body: <p>I am building a game with Xcode's spritekit.  Its a platform game and right now it functions well with flat ground pieces.  I was wondering if it was possible to ignore transparency in the png for collisions.  That is to say, If i have a ground piece with a curved floor and transparency filling the troughs, can i make the player walk the curves instead of a square bounding box covering the whole thing?  The only example i can find is in the Gamemaker GML language, you can do "precise" collisions such that blank space in the images do not count as part of the sprite. I can supply code if necessary but this seems like more of a conceptual question. Thanks in advance</p>