1214759 - layout/generic/test/test_selection_underline.html fails under Skia content from buggy dashed line optimization

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Lee Salzman [:lsalzman]]

The test layout/generic/test/test_selection_underline.html is currently failing when using Skia as the content backend. This is due to a dashed line optimization in Skia that is applying to the reference but not the test case itself, with slightly different rendering results.

Comment 1

[Lee Salzman [:lsalzman]]

Attachment: backport SkDashPathEffect::asPoints fix from upstream Skia

SkDashPathEffects::asPoints fails to apply in some situations. This is because a tangent vector was being normalized and compared exactly to 1. Since normalizing a vector may result in values close-to-but-not-exactly 1, this fails.

Skia fixed this upstream by using an inexact comparison, so this is just a straight backport of their fix and shouldn't pose a problem with updates.

It makes the effect optimization apply to the test-case so it matches the ref and thus passes.

Comment 2

[Lee Salzman [:lsalzman]]

Try results: https://treeherder.mozilla.org/#/jobs?repo=try&revision=dcb74cb20086

Comment 3

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/92a790ce42a3

Comment 4

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/92a790ce42a3

Comment 5

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/92a790ce42a3