Re: [csswg-drafts] [css-borders-4][css-shapes-1]The `round` algorithm is not continuous (#13914)

> @noamr So the issue here is that this isn't CSS border rounding at all, anymore, it's SVG path stroking. You can see the larger difference right here in the example - an *actual* border-radius:1px with a 20px border-width would produce a 1px inner corner and 21px outer corner, not this 0px inner and 10px outer that you get from stroking (because the line is actually in the middle of the stroke, not the "inner" surface, so the "outer" corner only grows by 10px rather than 20px).
> 
> Meanwhile, if you make a `<rect ... rx=.1>` in SVG and stroke it with a 20px stroke, you see the same results as here - a sharp transition from sharp corner, to weird angled corner, to rounded corner, as you change the rx from 0 to 1.
> 
> Are you thinking we solve this for SVG paths in general, then?

SVG (or canvas) doesn't try to optimize for transitioning between round and flat.
Since we "solved" it for border radius I think we can solve it for rounded polygons as well in a similar fashion if we want to optimize for that transition. We don't have to treat rounded polygons as exact strokea of a path. 

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Received on Wednesday, 13 May 2026 06:38:08 UTC