Impl copyTexImage2D and copyTexSubImage2D
- [X] `./mach build` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes
Implement copyTexImage2D and copyTexSubImage2D for WebGLRenderingContext. Feedback would be appreciated. I did my best to follow the [spec](https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.8). Please let me know if I missed anything. I couldn't find tests for this. Let me know if I should create one. I'm more than happy to do so. As always any feedback, comments,or critiques are very welcome 😄
Part of #10209
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It's a pointless abstraction that propagates the obsolete chan terminology,
swaps the order in which the sender and receiver are returned, and hides a
source of panics.
webgl: Implement the pending texImage2D overload, and add more validation
This is a large-ish refactor of the Texture2D code, but it should be
easier to read and of course more correct.
I tried to annotate every error condition with a spec paragraph.
I made just a reftest to ensure this works as intended, since I expect #10373 to land pretty soon.
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It's broken for uniform arrays, since uniform.id() stops being the index
then.
We need to add a more complex integration with angle for this to ever
be correct.
Unfortunately the ANGLE part that we should touch is C++, and it has
destructors, so we need to hook destructors there, and I can't do it
right now.
This is a large-ish refactor of the Texture2D code, but it should be
easier to read and of course more correct.
I tried to annotate every error condition with a spec paragraph.
This allows keeping the VertexAttrib* calls asynchronous.
Another option would be to do the validation in the apply() function,
but that'd require us passing an unnecessary channel around and add
extra synchronization.
The counterpart of this is that it has to be updated when the context
changes, but that's less problem.
WebRender is an experimental GPU accelerated rendering backend for Servo.
The WebRender backend can be specified by running Servo with the -w option (otherwise the default rendering backend will be used).
WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!
