Re: [csswg-drafts] [css-color] color-contrast() should support ranges of candidate colors, not just discrete color candidates (#7360)

The CSS Working Group just discussed `Ranges of Candidate Colors`, and agreed to the following:

* `RESOLVED: punt for now, revisit later`

<details><summary>The full IRC log of that discussion</summary>
&lt;fantasai> Topic: Ranges of Candidate Colors<br>
&lt;lea> github: https://github.com/w3c/csswg-drafts/issues/7360<br>
&lt;emilio> lea: there's a discontinuity between how designers design UI and how the contrast-color() function works<br>
&lt;emilio> ... they often have a base color and adjust coordinates (usually lightness) to get sufficient contrast<br>
&lt;emilio> ... right now it's possible but you'd need to provide a bunch of colors to simulate a range<br>
&lt;emilio> ... it'd be nice if you could simplify that usage<br>
&lt;emilio> ... not sure if it would need special syntax, or even if we want to do this<br>
&lt;astearns> ack dbaron<br>
&lt;emilio> ... we might want to punt on it and do it only if people actually do this<br>
&lt;emilio> dbaron: when you suggested syntax, before you said gradient my initial reaction was to use the interpolation syntax<br>
&lt;lea> q?<br>
&lt;emilio> ... I think you could reuse the interpolation syntax without specifying the end<br>
&lt;emilio> ... it's basically gradient without direction / radial stuff<br>
&lt;emilio> ... other thought is that this is difficult to explain with multiple contrast functions<br>
&lt;lea> q+<br>
&lt;emilio> ... if you specify something that's a range of color we specify the order in which you process them in<br>
&lt;emilio> q+<br>
&lt;astearns> ack lea<br>
&lt;TabAtkins> q+<br>
&lt;emilio> lea: I think before we dive down into details we should decide if we want to pursue this<br>
&lt;emilio> ... what that syntax would look like is secondary<br>
&lt;astearns> ack emilio<br>
&lt;fantasai> emilio: I think I'd rather act on it for now<br>
&lt;fantasai> emilio: there are a bunch of things to figure out, e.g. what are the steps you use for lightness?<br>
&lt;fantasai> emilio: what's the resolution of all the colors you try?<br>
&lt;fantasai> emilio: you may try 1000s of colors to find somehting<br>
&lt;fantasai> emilio: seems a bit unpredictable, perf-wise<br>
&lt;lea> q+<br>
&lt;fantasai> emilio: I guess you can binary search, maybe?<br>
&lt;astearns> evaluating all the colors for multiple algorithms seems expensive<br>
&lt;fantasai> emilio: assuming contrast is alwasy increasing or decreasing<br>
&lt;lea> q-<br>
&lt;fantasai> emilio: so unless we find ppl actually doing this,<br>
&lt;dbaron> yeah, I think you can't assume that contrast is always increasing/decreasing<br>
&lt;fantasai> emilio: if you pass 1000 colors, then worst case you evaluate 1000 colors<br>
&lt;fantasai> emilio: For now I'd rather defer this<br>
&lt;fantasai> emilio: I'd rather get the bits we know we want right, and then if we want to extend, we can always do it<br>
&lt;astearns> ack TabAtkins<br>
&lt;emilio> TabAtkins: you can't assume contrast is monotonic if you interpolate hue<br>
&lt;emilio> ... so sampling frequency becomes important<br>
&lt;lea> I actually agree<br>
&lt;fantasai> s/rather act/rather punt/<br>
&lt;emilio> ... so I say we punt for now<br>
&lt;lea> RESOLVED: punt for now, revisit later<br>
&lt;lea> github: https://github.com/w3c/csswg-drafts/issues/5153<br>
&lt;emilio> github: https://github.com/w3c/csswg-drafts/issues/7360<br>
</details>


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Received on Tuesday, 2 August 2022 20:07:13 UTC