[css-images-4] Computed value of stripes()

[fantasai]

The current spec says that the computed value of stripes() has all length-percentage values “absolutized and computed to the extent possible”. For border widths, that means it'll resolve to an absolute length.

However, I suspect we want to keep percentages uncomputed for inheritance, if we ever do use this in an inherited property, so I propose to use the same formulation as width etc. rather than line-height.

[SebastianZ]

However, I suspect we want to keep percentages uncomputed for inheritance, if we ever do use this in an inherited property, so I propose to use the same formulation as width etc. rather than line-height.

But percentages in width do get computed to a <length>. If we keep percentages (and <flex> values) uncomputed, how would you transition between different values? See also #8163 (comment) and generally the discussion there.

Sebastian

[Loirooriol]

Percentages in width compute as-is, not to a length. In this testcase, width: inherit sees 50% instead of the resolved width.

[SebastianZ]

Percentages in width compute as-is, not to a length. In this testcase, width: inherit sees 50% instead of the resolved width.

You're right. I mixed up the resolved value from getComputedStyle() with the computed value.

Because @fantasai already changed the spec. to keep percentages unchanged, I close this issue now. Feel free to re-open it if I missed anything.

Sebastian

[SebastianZ]

Having said that, #8163 (comment) outlines a reason why keeping percentages as-is restricts us regarding transitions.

Sebastian

[tabatkins]

Actually, I think this was better initially, where flexes were computed to lengths eagerly. That solves the transition issue immediately and clearly, without needing further interventions as I outlined in my comment.

And as stripes are essentially an image type, I find it very unlikely that they'll ever be used in an inherited property.

[SebastianZ]

I added #8622 to the agenda, which will also cover the things discussed here. The proposal is to adopt Tab's suggestion from above.

I assume, if there's a real need to add stripes() to an inherited property at some point, we could still account for that in that specific context.

Sebastian