Since wgpu hasn't yet released a version with this feature, I manually
backported it to the 0.17 branch.
This doesn't work on Windows (HLSL), but works on all other platforms.
* core: add temporary, ruffle-internal copy of `gc-arena` crate
This will allow bumping the upstream `gc-arena` version while
reexporting our own version of the old `GcCell` API, so that
Ruffle's code can be gradually migrated.
Once the migration is done, this crate should be removed.
* core: bump `gc-arena` to kyren/gc-arena#56
Add back the removed `GcCell` to our internal facade crate
* core: bump `gc-arena` to current master
This bump renames `Gc::allocate` to `Gc::new`
* core: rename `GcCell::allocate` to `GcCell::new`, to match `Gc`
* core: bump gc-arena to (slighly after) v0.3.1
Add typedefs for old `*Context` names in the gc-arena facade crate
* core: replace uses of `CollectionContext<'_>` by `&Collection`
* core: Add `gc()` convenience method for `*Context` and `Activation` types
This allows shortening most instances of `[activation.]context.gc_context`
to `activation.gc()` or `context.gc()` (but not all instances, because of
borrowck) Note that this doesn't actually do these shortenings to avoid
major code churn.
* 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
Nathan Adams