1058173 - Container layer has incorrect (Shadow)VisibleRegion

Status: RESOLVED INCOMPLETE

(Core :: Graphics: Layers, defect)

Description

[Benoit Girard (:BenWa)]

Attachment: Layer tree showing bug

bug 1010584 has a patch to do culling based on a layers' visible region. layout/reftests/async-scrolling/element01.html is failing. Upon closer inspection it has a container with an empty visible region. This is incorrect because we cull based on that an omit to draw the children which are visible according to how we draw container layers.

Comment 1

[Benoit Girard (:BenWa)]

Attachment: Layer tree from content

The bad value is coming from content

Comment 2

[Benoit Girard (:BenWa)]

Attachment: Display list

Comment 3

[Benoit Girard (:BenWa)]

Ok so this happens with ScrollInfoLayer display item. If the contents are a thebes layer then everything is fine. If the content are promoted a color layer then the thebes layer is kept with no visible region. The container layer for the ScrollInfoLayer then seems to copy the visible region from the thebes layer and not the color layer.

Comment 4

[Kartikaya Gupta (email:[e-mail])]

Without a test page that exercises this behavior this bug is not really actionable. And anyway we got rid of scroll info layers for most things now so this bug probably went away already.