Re: [csswg-drafts] [css-color-hdr] How should checking for percentages summing to 0 work in dynamic-range-limit-mix() when calc() is used? (#11678)

The CSS Working Group just discussed `[css-color-hdr] How should checking for percentages summing to 0 work in dynamic-range-limit-mix() when calc() is used?`, and agreed to the following:

* `RESOLVED: remove the sentence in spec that says if sum is zero, treat as invalid; possibly add new prose about splitting the percentage, and update tests`

<details><summary>The full IRC log of that discussion</summary>
&lt;jcraig> weinig: issue is that the spec for dynamic color mix has rules applied at parse time that check if value is zero<br>
&lt;jcraig> if all percentages add up to zero, they are invalid, but calc() may not know if it's invalid yet<br>
&lt;jcraig> options: either define at calc time what do in that scenario, mark as invalid at computed style time, or have it behave as if all percentages are the same; evenly divided<br>
&lt;jcraig> someone brought up the a concern with 50 high 50 low example, nothing constrained, you'd get 33/33/33 (not sure if I scribed that correctly)<br>
&lt;jcraig> currently we even split it, but worth considering when animating the ramps to zero<br>
&lt;jcraig> ChrisL: people will ramp it for animation so we should ensure it's not jarring<br>
&lt;jcraig> weinig: no current test for that.... but yes, should fix that<br>
&lt;jcraig> propose if all zero, treat as all at 33%<br>
&lt;jcraig> ChrisL: sounds reasonable<br>
&lt;jcraig> proposal: remove the sentence in spec that says if sum is zero, treat as invalid<br>
&lt;jcraig> weining: i can take on an item to work up the correct prose for that change to splitting the percentage<br>
&lt;jcraig> s/treat as invalid/treat as invalid; possibly add new prose about splitting the percentage, and update tests/<br>
&lt;jcraig> astearns: no objections resolved...<br>
&lt;jcraig> rrsagent, make minutes<br>
&lt;RRSAgent> I have made the request to generate https://www.w3.org/2025/02/26-css-minutes.html jcraig<br>
&lt;jcraig> RESOLVED: remove the sentence in spec that says if sum is zero, treat as invalid; possibly add new prose about splitting the percentage, and update tests<br>
</details>


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Received on Wednesday, 26 February 2025 20:19:53 UTC