904304 - Firefox transform3D CSS appears broken when there are large amount of elements with transform3D present on the page.

Status: RESOLVED WORKSFORME

(Core :: Layout, defect)

Description

[Silent Imp]

Attachment: bug.zip

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1500.95 Safari/537.36

Steps to reproduce:

Create large amount of elements with 3D Transformation applied.


Actual results:

Wrong visibility calculation. Elements cover each other in wrong order.



Expected results:

Right visibility calculation.

Comment 1

[Silent Imp]

problem is common for all FF versions

Comment 2

[Silent Imp]

Attachment: this is screenshot of expected behaviour

Comment 3

[Silent Imp]

Attachment: this is screenshot of behaviour in Gecko on a small amount of elements

Comment 4

[Silent Imp]

Attachment: this is screenshot of behaviour in Gecko on a big amount of elements

Comment 5

[Robert O'Callahan (:roc) (email my personal email if necessary)]

I assume this is just the lack of plane splitting. Currently we have some heuristics for z-ordering 3D transformed elements that don't always work. I.e., bug 689498.

Comment 6

[:kip (Kearwood Gilbert)]

In addition to the plane splitting being required for correct rendering in many cases, there is currently a hard-coded limit to the number of layers that will be sorted:

https://dxr.mozilla.org/mozilla-central/source/gfx/layers/LayerSorter.cpp?from=LayerSorter.cpp&case=true#236

This is currently set to 100.  When the layer sorting is fixed, this limit will be bumped up to a more reasonable ceiling that is less likely to be hit.

Comment 7

[Gregory Pappas [:gregp]]

This demo renders correctly now.