Add support for display-p3 canvas and ImageData

• Component: Canvas
• Status: RESOLVED FIXED

[Christopher Cameron]

Proposal document:
https://github.com/WICG/canvas-color-space/blob/main/CanvasColorSpaceProposal.md

Syntax for creating such a canvas is
     var context = canvas.getContext('2d', {colorSpace:'display-p3'});

Similar syntax for use with ImageData.

Corresponding bugs:
Chromium: crbug.com/1083693
Mozilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1703654

[Sam Weinig]

Created attachment 427308 [details]
basic test case

[Sam Weinig]

Created attachment 427309 [details]
Proof of concept patch that gets things working

[Sam Weinig]

Created attachment 427479 [details]
Now with ImageData support

[Christopher Cameron]

Very excited to see this!

There are a couple of things that changed from the proposal to what was agreed upon in the WhatWG PR. To draw your attention to them:

* The PredefinedColorSpace interface to query for valid PredefinedColorSpaceEnum values is gone. There's just PredefinedColorSpace as an enum (with "srgb" and "display-p3" as options). 

* For ImageDataSettings, the PredefinedColorSpace is optional. The canvas methods getImageData and createImageData will use the color space of the canvas if colorSpace was not specified in ImageDataSettings.

* The ImageBitmap part was taken out (ImageBitmapOptions will change to have an optional PredefinedColorSpace, rather than a required one, so that the ImageBitmap will default internally to "whatever is the best internal color space")

I think that's it. We're working on upstreaming WPT tests for all of this. Feel free to reach out.

[Sam Weinig]

(In reply to Christopher Cameron from comment #4)
> Very excited to see this!
> 
> There are a couple of things that changed from the proposal to what was
> agreed upon in the WhatWG PR. To draw your attention to them:

Great. Thanks for letting me know and continuing to drive this.

Is that PR up for review anywhere?

[Sam Weinig]

(In reply to Sam Weinig from comment #5)
> (In reply to Christopher Cameron from comment #4)
> > Very excited to see this!
> > 
> > There are a couple of things that changed from the proposal to what was
> > agreed upon in the WhatWG PR. To draw your attention to them:
> 
> Great. Thanks for letting me know and continuing to drive this.
> 
> Is that PR up for review anywhere?

Found it. Better yet, it is now in main!

https://github.com/whatwg/html/commit/85cb202a052c462bd6830b3dda96e7edbd1dcd75

[Sam Weinig]

Tracking initial support (no ImageData) in https://bugs.webkit.org/show_bug.cgi?id=225286.

[Radar WebKit Bug Importer]

<rdar://problem/77542907>

[Sam Weinig]

ImageData support now being worked on in https://bugs.webkit.org/show_bug.cgi?id=225841.

[Sam Weinig]

Additional things to do after ImageData:
- Ensure it works and add tests for drawing non-sRGB CanvasImageSources (image, videos, other canvases) into canvas (including patterns).
- Ensure it works and add tests for drawing non-sRGB gradients.
- Ensure it works and add tests for drawing non-sRGB shadows.

[Cameron McCormack (:heycam)]

We can consider this done.

[Cameron McCormack (:heycam)]

*** Bug 188320 has been marked as a duplicate of this bug. ***