[csswg-drafts] [css-backgrounds][css3-background] Consider removing the spread distance adjustment for small border radii

mstange has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-backgrounds][css3-background] Consider removing the spread distance adjustment for small border radii ==
https://drafts.csswg.org/css-backgrounds-3/#shadow-shape contains this piece of text:

> However, in order to create a sharper corner when the border radius is small, when the border radius is less than the spread distance, the spread distance is multiplied by the proportion 1 + (r-1)^3, where r is the ratio of the border radius to the spread distance, in calculating the corner radii of the spread shadow shape.

This seems to have originally been added in this commit: https://github.com/w3c/csswg-drafts/commit/170e7532494d4cadd7eca8bc86d9fbf2a25767fb

Has this been implemented by any browser? Firefox has not implemented it, and judging by the code [here](https://chromium.googlesource.com/chromium/src/+/85c12763181253aab7759f5e18ddf93f485ff304/third_party/WebKit/Source/core/paint/BoxPainterBase.cpp#140) and [here](https://chromium.googlesource.com/chromium/src/+/85c12763181253aab7759f5e18ddf93f485ff304/third_party/WebKit/Source/platform/graphics/GraphicsContext.cpp#510), Chrome hasn't either.

If there has been no interest from browser vendors, it may be a good idea to remove this section again.

If you decide to keep it, I think the case where the spread amount is negative needs some clarification (and the math may need to be double-checked).

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/1900 using your GitHub account

Received on Monday, 23 October 2017 22:14:37 UTC