Bug 252043

Summary:	display-p3 isn't supported as interpolation color space
Product:	WebKit	Reporter:	Melvin <melvin.idema30>
Component:	CSS	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Trivial	CC:	heycam, m_dubet, ntim, sam, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	Safari Technology Preview
Hardware:	Mac (Apple Silicon)
OS:	macOS 13

Description Melvin 2023-02-10 03:47:34 PST

When I try to use the color-mix() function in combination with the Display-P3 color function, the function breaks. This is because the first argument, the color-space, is not supported by the color-interpolation-method as defined in CSS Color Module 5. However, it seems like CSS Color Module 5 suggests that one can give a @color-profile as color-interpolation-method in the color-mix() function like this:

color-mix(<dashed-ident>, <color> <percentage, <color>);

Expected Behavior: The color-mix() function should work correctly with the Display-P3 color, creating a mix of two colors in the specified color-space. Or at least work correctly with dashed-ident's and custom @color-profile.

Steps to Reproduce: Try to use the color-mix() function in combination with Display-P3 or @color-profile on Safari 16 or Technology Preview

Comment 1 Tim Nguyen (:ntim) 2023-02-10 17:49:09 PST

`data:text/html,<span%20style="color:%20color-mix(in srgb, color(display-p3%201%200.5%200)%2050%,%20transparent)">dfsdfsdfsdfdsf</span>` seems to work for me. 

Do you have a testcase that doesn't work for you?

Comment 2 Melvin 2023-02-11 10:44:38 PST

Thank you for your response Tim! 

In the provided example the color-space srgb is used instead of display-p3. The function breaks if you try to use display-p3. Like this:

`data:text/html,<span%20style="color:%20color-mix(in display-p3, color(display-p3%201%200.5%200)%2050%,%20transparent)">dfsdfsdfsdfdsf</span>`

In my original comment I described using a custom color space as value in color-mix however I now realize custom color spaces aren't yet supported.

Comment 3 Tim Nguyen (:ntim) 2023-02-11 10:50:50 PST

Ah right, it should work according to https://drafts.csswg.org/css-color/#interpolation-space , thanks!

Sam, do you know if this is a known bug?

Comment 4 Radar WebKit Bug Importer 2023-02-17 03:48:17 PST

<rdar://problem/105591773>

Comment 5 Matthieu Dubet 2024-02-05 15:25:32 PST

Yes we don't support display-p3 yet as an interpolation method.

https://github.com/WebKit/WebKit/blob/main/Source/WebCore/css/parser/CSSPropertyParserHelpers.cpp#L2894