1577337 - wizard of oz easter egg still not quite optimal even with webrender

Status: RESOLVED WONTFIX

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

Description

[Markus Stange [:mstange]]

From bug 1576404:

STR:

1. Visit www.google.com
2. Search "wizard of oz"
3. click the red shoes on the right of the page. This will do a spinning animation that is janky
4. Click the tornado where the shoes were and the animation will reverse

WebRender does a lot better than non-WebRender Firefox on this page, but it's still a bit janky. It also seems to allocate tons of render targets. WebRender can do better still.

Comment 1

[Nicolas Silva [:nical]]

The page is fairly expensive to render, mostly because the majority of the pixels are blurred and because having a non-axis-aligned transform on all elements moves a lot of work to the alpha pass. In general though we are not running into any pathological case.

We could improve this significantly by caching the transformed picture untransformed and then apply the transform when compositing it each frame (This is what layers-based browsers tend to do in this type of situation).
If we could also cache the blur we'd save a ton of GPU work as well (it would require us to reorder the transform and the blur which would work here but may not be trivial to generalize correctly).

Comment 2

[Glenn Watson [:gw]]

Easter egg no longer appears to exist.