1351131 - (wr-displayitems) [meta] Display Item Conversion

Status: RESOLVED FIXED

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

Description

[Mason Chang [Inactive] [:mchang]]

We have bugs all over the place to track display item layer conversions. Let's make this the default meta. 

The giant list of items: https://public.etherpad-mozilla.org/p/wr-plan#lineNumber=167


As of today:
Open - 
Background
ThemedBackground
nsDisplaySVGGeometry
Gradients - Bug 1347469 - Add gradient border support in quantum render.
Background image gradients - https://bugzilla.mozilla.org/show_bug.cgi?id=1341101
AltFeedback - https://bugzilla.mozilla.org/show_bug.cgi?id=1345388
Bullet - https://bugzilla.mozilla.org/show_bug.cgi?id=1349500 
ColumnRule - https://bugzilla.mozilla.org/show_bug.cgi?id=1344079
TableBorderBackground - https://bugzilla.mozilla.org/show_bug.cgi?id=1344082

Done
Image - https://bugzilla.mozilla.org/show_bug.cgi?id=1345053 - Done
Text - https://bugzilla.mozilla.org/show_bug.cgi?id=1329314 - Done
ButtonBorderBackground - https://bugzilla.mozilla.org/show_bug.cgi?id=1343979 - Done
ButtonForeground - https://bugzilla.mozilla.org/show_bug.cgi?id=1344622 - Done
CanvasBackgroundColor - https://bugzilla.mozilla.org/show_bug.cgi?id=1343450 - Done
BackgroundColor - https://bugzilla.mozilla.org/show_bug.cgi?id=1349497 - Done
Border - Bug 1322079 - Add support for border layers in WebRender LayerManager/Bridge code - Done
Outline - https://bugzilla.mozilla.org/show_bug.cgi?id=1348755

Items that don't need work:
https://bugzilla.mozilla.org/show_bug.cgi?id=1344002#c2
sDisplayTransform, nsDisplayBlendMode, nsDisplayBlendContainer, nsDisplayMask, nsDisplayOwnLayer, nsDisplayOpacity

Comment 1

[Mason Chang [Inactive] [:mchang]]

Done: Box shadow inset - bug 1349843

Comment 2

[Mason Chang [Inactive] [:mchang]]

Outer box shadows, almost done - 1347727

Comment 3

[Mason Chang [Inactive] [:mchang]]

Background image - bug 1351242

Comment 4

[Mason Chang [Inactive] [:mchang]]

Text overflow marker - bug 1351508
Bug 1351510 - Conver nsDisplaySolidColor to a WebRender Display Item
Bug 1351511 - Convert nsSolidColorRegion to WR DisplayItems

Comment 5

[Mason Chang [Inactive] [:mchang]]

Attachment: Display item usage telemetry chart

A chart of how many times a display item of a certain type was created compared to all the display items that were created. We see that we don't actually have that many items.

Top 10 are:
1) Layer event regions (27%)
2) text (26%)
3) Background color (13.5%)
4) background (5.8%)
5) border (5.6%)
6) Image (4%)
7) opacity (3.5%)
8) Transform (2.1%)
9) SVG Geometry (1.9%)
10) button border background (1.8%)

Comment 6

[Jamie Nicol [:jnicol]]

It'd also be interesting to see what percentage of display lists each type of display item is present in. eg There would only be one CanvasBackgroundColor per display list, so it is quite low down this list. But it is present in basically every page, (and takes up a large area) so is important that we convert it. I realise this particular example is already implemented, but there might be others.

Comment 7

[Jeff Muizelaar [:jrmuizel]]

I think it would give a more accurate picture to only count each display item once per page.

Comment 8

[Milan Sreckovic [:milan] (needinfo for best results)]

Note: please keep the status of DI up to date in this etherpad: https://public.etherpad-mozilla.org/p/wr-status

Comment 9

[Mason Chang [Inactive] [:mchang]]

I did some local profiling to see what display items are actually slow. The list is surprisingly small. In order of importance:

1) Background
2) Text
3) Images
4) Box Shadows both inner and outer
5) nsDisplaySVGGeometry

After browsing for quite some time, it's rare that we see other display items ever take more than 1 ms to render.

Backgrounds wildly vary, but by far are much slower than every other item. Sometimes I've seen 300 +ms to render a background.
Text is next, but most of the time takes 1-2 ms, with max of ~30ms.
Next are images, usually take 3-4 ms with a max of ~8ms
Finally box shadows with average 1-2ms with maxes of 5ms.
SVG Geometry ~1-2ms.

All tests done on Windows 10 w/ d2d on a late 2013 MacBook pro + NVidia gpu.

Comment 10

[Mason Chang [Inactive] [:mchang]]

Also once in a very rare while, borders can sometimes take ~5ms.

Comment 11

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

Old metabug, no open deps, closing.