846218 - [Homescreen] Dragging performance enhancement

Status: RESOLVED FIXED

(Firefox OS Graveyard :: Gaia::Homescreen, defect, P1)

Description

[Leo]

We have tested the dragging performance on leo device using the high speed camera. The result of the dragging is 46fps. We need to improve the performace of dragging over 50fps.

Comment 1

[Cristian Rodriguez (:crdlc)]

Attachment: First patch

https://github.com/crdlc/gaia/tree/846218

Sorry, because I don't have leo devices, could you tell me if fps are better with this patch? 

Thanks

Comment 2

[Cristian Rodriguez (:crdlc)]

Attachment: Less allocations

Comment 3

[Cristian Rodriguez (:crdlc)]

Attachment: Patch v3

https://github.com/crdlc/gaia/tree/846218

This patch is based on the idea to avoid reflows while dragging

Comment 4

[Cristian Rodriguez (:crdlc)]

Attachment: Patch v4

Basically I've re-implemented some functions in order to achieve more fps dragging. The great goal here is to avoid reflows while dragging, keeping the elements that we animate and putting off the inserBefore operation when the user releases the finger and not between movements

Comment 5

[Cristian Rodriguez (:crdlc)]

https://github.com/mozilla-b2g/gaia/commit/ee236c942f2b9abe9065c2fb967b715770a43d9c

Comment 6

[Julien Wajsberg [:julienw]]

in case this is needed, I resolved the v1-train conflicts here :

https://github.com/julienw/gaia/commit/e71d872aa99d26d0016848501d77bf5ffdedaac8

The sensation when dragging is really better with this patch, I'm asking for tef+.

Cristian, do you think that we could use transitions and transformations to control the dragged icon too (in a follow-up bug of course) ?

Comment 7

[Michael Vines [:m1] [:evilmachines]]

(tef- from my POV as this isn't a key area of UI perf that we are tracking for v1.0.1)

Comment 8

[Cristian Rodriguez (:crdlc)]

> Cristian, do you think that we could use transitions and transformations to control the dragged icon too (in a follow-up bug of course)

Hi friend, sorry, could you explain me a bit more? Such as icons below dragged icon as this one are translated. Maybe I didn't understand the question jejeje. But sure I could always do something to improve Firefox OS!!

Comment 9

[Julien Wajsberg [:julienw]]

Well, with this patch, the icons that move on the homescreen because of the drag are not laggy anymore. However, the icon being moved is still laggy... is it clearer ?

Comment 10

[Cristian Rodriguez (:crdlc)]

umm alright, the icon that is being moved use mozRequestAnimationFrame, maybe, in your local laptop change

window.mozRequestAnimationFrame(move);

move()

and check results...

https://github.com/mozilla-b2g/gaia/blob/master/apps/homescreen/js/dragdrop.js#L240

Comment 11

[Peter Dolanjski [:pdol]]

Sandip, based on the performance targets that you are working off of, would we block the release on this?

Comment 12

[Julien Wajsberg [:julienw]]

v1-train: 160a4117c242aa45ca5b9cf7574e394f786832c8

Comment 13

[Julien Wajsberg [:julienw]]

Bug 854610 is tracking a regression.

Comment 14

[Julien Wajsberg [:julienw]]

marking 1.0.1 wontfix per comment 7