LibGDX has a coordinate system where (0,0) is at the bottom-left. (like this image: http://i.stack.imgur.com/jVrJ0.png)
This has me beating my head against a wall, mainly because I'm porting a game I had already made with the usual coordinate system (where 0,0 is in the Top Left Corner).
My question: Is there any simple way of changing this coordinate system?
If you use a Camera (which you should) changing the coordinate system is pretty simple:
camera= new OrthographicCamera(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
camera.setToOrtho(true, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
If you use TextureRegions and/or a TextureAtlas, all you need to do in addition to that is call region.flip(false, true).
The reasons we use y-up by default (which you can easily change as illustrated above) are as follows:
The only two places in libgdx where we use y-down are:
Again, you can easily change the used coordinate system to whatever you want using either Camera or a tiny bit of matrix math.