Bug 114402 – [CSS Exclusions] polygon shape-inside layout fails

• Component: CSS
• Status: RESOLVED FIXED

[Hans Muller]

Created attachment 197456 [details]
Test case screenshot.

As can be seen in the attached screenshot, there's a large gap in the text where no gap should be.

[Hans Muller]

Created attachment 197457 [details]
Test case.

[Hans Muller]

Created attachment 198349 [details]
Simplified test case screenshot.

[Hans Muller]

Created attachment 198350 [details]
Simplified test case.

This version of the test case uses the Ahem font and just a few single-character lines of text to demo the problem.

[Hans Muller]

Created attachment 198388 [details]
Patch

[Hans Muller]

Comment on attachment 198388 [details]
Patch

The firstIncludedIntervalLogicalTop() method's implementation relied on optimistic assumptions about floating point accuracy which, in rare cases, caused it to discard first-fit locations based on the intersection of the minLogicalIntervalTop offset edge and a polygon offset edge. Now: we do not verify that first-fit locations based on the intersection of an offset edge and the minLogicalIntervalTop offset edge are below the horizontal minLogicalIntervalTop line. They're essentially below the line "by definition".

[Dirk Schulze]

Comment on attachment 198388 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=198388&action=review

r=me. Just some editorial change requests.

> Source/WebCore/ChangeLog:18
> +        (WebCore::ExclusionPolygon::firstIncludedIntervalLogicalTop): Avoid floating point problems when checking intersections with the offset edge based on minLogicalIntervalTop.

Split the comment into two lines.

> Source/WebCore/ChangeLog:21
> +        (WebCore::OffsetPolygonEdge::basis): Report what the offset edge is "based on": a polygon edge, the top of the line, or a (reflex) vertex.

Ditto.

> Source/WebCore/rendering/ExclusionPolygon.h:41
> +    enum Basis { Edge, Vertex, LineTop };

I'd like to have a new line for each enum item. This is usually used nowadays.

[Hans Muller]

Created attachment 198447 [details]
Patch

Made the changes that Dirk suggested.

[WebKit Commit Bot]

Comment on attachment 198447 [details]
Patch

Clearing flags on attachment: 198447

Committed r148582: <http://trac.webkit.org/changeset/148582>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.