Right Round

Hey guys,
Before I start, I wanna thank Lizard-13 and everyone else for being so awesome!
As you all know, I’m trying to make a round platform world. Could I make a giant circle Sprite, change the collision mask, and go from there?

In case you mean to walk around the circle, the circle definitely can not be a platform and you definitely can not make it collision mask to be a perfect circle as it requires lot of collision points and that is really bad for performance. You need to make your very own platformer engine from scratch with circle shaped platforms in mind which is definitely involve lot of calculations to make
Personally I can’t help you with that as I have never done it and probably not because the math part is not something I can deal with… The trouble is, in this kind of thing you definitely don’t want it to be a pure circle, you want platforms, slopes and ramps on the circle to walk on it, jump on to, fall from it while you walking around and that is the tricky part that you or someone need to figure out in first place and go from there.

So you definitely can not use the platformer behaviour for this thing unless you just want to rotate the circle below the player as we suggested before but then you need to deal with the same problems that made you think again and ask the same question again.

But what you could do, In case the player never walk upside down on the screen and the platform always fills the entire screen meaning you don’t see much from the actual circle shape, why don’t you just make the illusion of the player walking around by simply change it position at the end of the platform back to the beginning? Similar to Starbound for example. If you design the level to make the start position and the end position look the same and change the position the right moment, the player would notice nothing about it and have the impression of walking “around”.