ske: One draw call renderer.

[marekmaskarinec]

Original issue:

~mrms/tophat#41

Initial message:

The one draw call renderer should stop web version and desktop versions from lagging/overloading the computer, it should especially optimize the main problem tophat has, which is switching textures and scissor rects. Scissor rects will be implemented via shaders now, which reduces complexity of switching between draw calls. I might need some help. One important part of this technique is to pack images into one atlas image since you can't attach much more than a few textures per draw call.

[marekmaskarinec]

If I understand correctly, you want to implement scissor rects inside shaders now. Do we pass them as attributes (a lot of data, but few draw calls), or as uniforms (less data, more draw calls).

[skejeton]

Probably attributes, we can have only simple clipping shapes like quads. Anything more complex we can think about later, but we have more lee way since the pipeline is 2D not 3D.