* wpgu: Initial implementation of PixelBender shader execution
The implementation is split across four crates:
* `ruffle_render` now holds the main PixelBender bytecode parsing
implementation (previously, this was in `ruffle_core`).
* `ruffle_core` holds some helper functions for converting between
AVM2 `Value`s and the PixelBender vector types.
* `naga-pixelbender` (newly created) constructs a Naga `Module`
from parsed PixelBender bytecode
* `ruffle_render_wgpu` sets up the render pipeline for the shader
constructed by `naga-pixelbender`, and actually executes the shader.
The Actionscript-side shader parameters are passed in through uniforms.
This allows us to cache the compiled `naga::Module` and associated
wgpu types inside `ShaderData`, when it's first created. Each invocation
of a `ShaderJob` only needs to create a bind group and render pass.
Limitations:
* Only a few of the PixelBender opcodes are implemented - however, this is
enough to get Stemlands cannon rotation working, as well as a cool
"donut" shader that I found and included as a test.
* PixelBender matrix types are not supported.
* Only BitmapData is supported as an input/output type - Flash Player
also supports using Vector and ByteArray
* ShaderJob execution is always synchronous.
* Adjust comments
* Address review comments
* Bump bitflags to 2.0.0
* Sprinkle Clone, Copy, Eq, PartialEq, and Debug derives where needed
* Call `bits` on bitflags, as it is now a method
* Switch from `from_bits_truncate` to `from_bits_retain` on bitflags where needed
* Bump h263-rs for the bitflags 2.0.0 dependency
As part of porting to bitflags 2.0.0, see:
https://kodraus.github.io/rust/2022/10/07/bitflags2.html#upgrading-to-2x
This is the first part of the Stage3D implementation, and can
be reviewed independently.
Stage3D shaders use the Adobe Graphics Assembly Language (AGAL),
which is a binary shader format. It supports vertex attributes,
varying registers, program constants (uniforms), and texture sampling.
This PR only implements a few parts of AGAL:
* The 'mov' and 'm44' opcodes
* Vertex attributes, varying registers, program constants, and 'output'
registers (position or color, depending on shader type)
This is sufficient to get a non-trivial Stage3D program
running (the rotating cube demo from the Adobe docs).
The output of `naga-agal` is a `naga::Module`. This can be passed
directly to wgpu, or compiled into a shader language using
a Naga backend (glsl, wgsl, SPIR-V, etc). The test suite
output WGSL files, and uses the 'insta' crate to compare against
saved files on disk.
Currently, the only real way to write AGAL bytecode is using
the Adobe-provided 'AGALMiniAssembler' flash class.
This class assembles the textual reprentation of AGAL into
the binary format.
To make writing tests easier, I've added a 'agal_compiler' test, which
can easily be modified to add more Agal textual assembly.