Canvas2D: Add srgb-linear and display-p3-linear to PredefinedColorSpace enum

[ccameron-chromium]

Canvas2D: Add srgb-linear and display-p3-linear to PredefinedColorSpace enum

• At least two implementers are interested (and none opposed):
  • WebKit (see below)
  • Chromium (proposed)
• [/] Tests are written and can be reviewed and commented upon at:
  • https://chromium-review.googlesource.com/c/chromium/src/+/7082585
• Implementation bugs are filed:
  • Chromium: https://issues.chromium.org/issues/454152417
  • Gecko: https://bugzilla.mozilla.org/show_bug.cgi?id=1996208
  • WebKit: https://bugs.webkit.org/show_bug.cgi?id=301418
• MDN issue is filed:
  • Will file only after landing, per feedback from MDN
• The top of this comment includes a clear commit message to use.

(See WHATWG Working Mode: Changes for more details.)

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/canvas.html ( diff )
/infrastructure.html ( diff )

[annevk]

OP needs filling out. You can consider WebKit interested.

I think we should also have a follow-up issue on formalizing "color space" better. We say these values map to CSS-defined color spaces, but most of the "color space" concepts say they hold a PredefinedColorSpace as value, which seems wrong. We should translate from the string to the CSS color spaces and then use those throughout.

We'll also need tests for all the various things taking a PredefinedColorSpace.

[annevk]

What makes this requirement obsolete?

[ccameron-chromium]

Good catch -- this was a merge conflict badly resolved (this text had moved).

[ccameron-chromium]

I've updated the OP and added tests for the HTML APIs that use PredefinedColorSpace.

I've limited this change to only add the srgb-linear and display-p3-linear spaces that you requested, and not the original rec2100-linear. This is because I want to be very careful about making sure we get the details about rec2020 and rec2100-linear right.

In terms of replacing PredefinedColorSpace with all CSS color spaces, would you be thinking to do just predefined-rgb, or something more expansive (like oklab etc)?

[annevk]

I wasn't thinking of supporting more color spaces. I was mainly thinking of a mostly editorial change where we convert a PredefinedColorSpace to a CSS color space on input and then pass that around in the model instead of a PredefinedColorSpace (which is just a string and devoid of meaning).