Previously, we would always use a transparent background,
even if the BitmapData is not transparent. This would normally
be corrected on the next frame when we copied the pixels to the
CPU. However, if an SWF ran `BitmapData.draw` on every frame,
this would never be corrected.
When rendering offscreen, we want the resulting image to use
premultiplied alpha, since the image will be stored in a texture.
However, when capturing an image in the exporter or test framework,
we want to use straight alpha, so that the resulting image can
be saved as a PNG.
Previously, we incorrectly used straight alpha everywhere, resulting
in incorrect output when using BitmapData.draw with transparency.
Our AVM2 `SharedObject` support is now *almost* equivalent
to our avm1 `SharedObject` support. We implement serialization
and deserialization for primitives, arrays, and `Object` instances
with local properties. We also implement serialization for `Date`,
but not `Xml` (since our AVM2 `Xml` class is just a stub at the moment).
This is enough to make 'This is the only level too' save level
progress to disk.
Currently, we always serialize to AMF3. When we implement
the `defaultObjectEncoding` and `objectEncoding`, we'll need
to adjust this.
An AVM2 movie can repeatedly remove and add a DisplayObject from/to
a parent. This was causing SolarMax to stop working after advancing
to the next level.
We now check if a BitmapData has been disposed by checking
for a zero width or height (which cannot happen otherwise).
As a result, we no longer need the 'disposed' field on the AVM1
BitmapData object.
The SWF19 specs incorrectly state DefineEditText tag only contains
font height if the HasFont flag is set. The tag also contains
the height if the HasFontClass flag is set. This indicates that a
font is used via runtime sharing.
* avm2: Implement `BitmapData.draw` for `wgpu` backend
This method requires us to have the ability to render directly to a
texture. Fortunately, the `wgpu` backend already supports this in
the form of `TextureTarget`. However, the rendering code required
some refactoring in order to avoid creating duplicate `wgpu` resources.
The current implementation blocks on copying the pixels back
from the GPU to the CPU, so that we can immediately set them in
the Ruffle `BitmapData`. This is likely very inefficient, but will
work for a first implementation.
In the future, we could explore allowing the CPU image data and GPU
texture to be out of sync, and only synchronized when explicitly
necessary (e.g. on `getPixel` or `setPixel` calls).
* Rename `with_offscreen_backend` to `render_offscreen` and use Bitmap
* Don't panic when backend doesn't implement `render_offscreen`
We already have `&mut self` available whenever we write to it,
and we never made use of the `Clone` impl. As far as I can tell,
we don't have any unimplemented features that would require a `GcCell`.