1206704 - ContainerLayerOGL doesn't deal well with big intermediate surfaces

Status: RESOLVED INVALID

(Core :: Graphics: Layers, defect, P3)

Description

[Markus Stange [:mstange]]

Attachment: testcase

Steps to reproduce:
 1. Load the testcase on a Retina Macbook Pro using the integrated GPU.
 2. Start scrolling.

The blue box disappears and the green box gets scaled up.

This happens because the opacity requires an intermediate surface to be used during compositing, and the size of this intermediate surface exceeds the maximum texture size.

The size of the intermediate surface is based on the visible region of the container layer. The second patch in bug 1136766 clips the visible region before compositing if the container layer's transform is just an integer translation, so it will help in some cases but not in all.

Comment 1

[Markus Stange [:mstange]]

(In reply to Markus Stange [:mstange] from comment #0)
> The second patch in bug 1136766 clips the visible region
> before compositing if the container layer's transform is just an integer
> translation, so it will help in some cases but not in all.

That patch has now moved to bug 1021845 and deals with all transforms, not just integer translations. However, there can still be cases where even the clipped intermediate surface is bigger than the maximum texture size. We still need a solution for those cases.

Comment 2

[Liz Henry (:lizzard) (relman/hg->git project)]

Is this still an issue for 46? Thanks.

Comment 3

[Markus Stange [:mstange]]

Bug 1021845 took care of it mostly - instead of learning to deal with big intermediate surfaces, we just create smaller intermediate surfaces. There are still some cases where we can't do that, so it would be nice to fix this one, but it's not a high priority.