This commit reduces the workgroup shared memory of binning to fit in
16k (by packing two u16's in a u32), and moves the config binding to
uniform, from readonly storage.
Progress toward #202
As stated by the README, the intention is for the shaders to be
provided under the terms of the Unlicense in addition to the MIT
and Apache-2.0 licenses.
While here, add a self-contained UNLICENSE file to replace the
external reference to unlicense.org.
This is a checkpoint of partly completed work. Much of the GPU side is done, very little of the CPU side.
For clips, the clip_els bindings (binding 6 of draw_leaf) are not added. Clip logic is missing from coarse. The overflow buffer is missing from fine, as is its size calculation in coarse (but it should work as long as the max depth fits within BLEND_STACK_SPLIT).
For gradients, the texture binding is missing (binding 6) is missing from fine, as is the infrastructure in engine to deal with texture resources, and of course porting over the logic to fill it.
The code is not tested, bugs may lurk.
