1388299 - Enable OffscreenCanvas with WebGL 2

Status: RESOLVED DUPLICATE of bug 1736177

(Core :: Graphics: CanvasWebGL, enhancement, P3)

Description

[Jukka Jylänki]

It looks like OffscreenCanvas-based WebGL 2 contexts do not have the .commit() function. Enabling pref gfx.offscreencanvas.enabled to true, and running in web page console in Firefox Nightly 57.0a1 (2017-08-07) (64-bit) on Windows 10:

> > new OffscreenCanvas(128,128).getContext('webgl').commit()
> undefined
> > new OffscreenCanvas(128,128).getContext('webgl2').commit()
> TypeError: (new OffscreenCanvas(...)).getContext(...).commit is not a function

I wonder if this is due to some WebGL 2 specific enable check missing, or if there is something more fundamental that is needed to enable WebGL 2 on OffscreenCanvases?

Comment 1

[Daosheng Mu[:daoshengmu]]

(In reply to Jukka Jylänki from comment #0)
> It looks like OffscreenCanvas-based WebGL 2 contexts do not have the
> .commit() function. Enabling pref gfx.offscreencanvas.enabled to true, and
> running in web page console in Firefox Nightly 57.0a1 (2017-08-07) (64-bit)
> on Windows 10:
> 
> > > new OffscreenCanvas(128,128).getContext('webgl').commit()
> > undefined
> > > new OffscreenCanvas(128,128).getContext('webgl2').commit()
> > TypeError: (new OffscreenCanvas(...)).getContext(...).commit is not a function
> 
> I wonder if this is due to some WebGL 2 specific enable check missing, or if
> there is something more fundamental that is needed to enable WebGL 2 on
> OffscreenCanvases?

According to the spec, https://wiki.whatwg.org/wiki/OffscreenCanvas, commit() is not belong to OffscreenCanvas.

We already have it at WebGLRenderingContext when OffscreenCanvas is enabled. One thing you might be interested is our OffscreenCanvasRenderingContext2D::commit() is not implemented yet, https://dxr.mozilla.org/mozilla-central/source/servo/components/script/dom/webidls/CanvasRenderingContext2D.webidl#28

Comment 2

[Jukka Jylänki]

(In reply to Daosheng Mu[:daoshengmu] from comment #1)
> (In reply to Jukka Jylänki from comment #0)
> > I wonder if this is due to some WebGL 2 specific enable check missing, or if
> > there is something more fundamental that is needed to enable WebGL 2 on
> > OffscreenCanvases?
> 
> According to the spec, https://wiki.whatwg.org/wiki/OffscreenCanvas,
> commit() is not belong to OffscreenCanvas.

Sorry, I meant to write "if there is something more fundamental that is needed to enable WebGL 2 on GL contexts based on OffscreenCanvases?" Like the code shows, it is not attempting to access .commit() on OffscreenCanvas, but on a WebGL 1/2 context obtained from it.

Comment 3

[Milan Sreckovic [:milan] (needinfo for best results)]

Offscreen canvas not in 57.

Comment 4

[Andrew Osmond [:aosmond] (he/him)]

There were open questions about commit but otherwise OffscreenCanvas WebGL2 was implemented in with bug 1736177.