Still one flaw, fat lines aren't expanded with strokes in path coarse rasterization. But that's a small visual ding, and can be fixed
That said, there is some really strange stuff going on in tile_alloc. It's using storage to do a uniform broadcast (the result of bump allocation for the workgroup), which is not great at all. It should be using workgroup storage, but on my mac it behaves as if the workgroup barrier is not in place. Investigating.
The bones of coarse rasterization are in place (so far, fills only). Still not suitable for end-to-end (need to generate bounding boxes, among other things), but getting closer.
