863201 - [B2G] [Settings] Images with alpha channel are slow to decode/paint

Status: RESOLVED WONTFIX

(Core :: Graphics, defect)

Description

[Anthony Ricaud (:rik)]

In bug 840627, we discovered that using section logos with alpha channel was taking 180ms more on startup than using the same logos without an alpha channel. Because of that, we created two versions of those logos with the background hardcoded (inactive [1] and active state [2]). It's creating maintenance problems obviously but it also means decoding an extra sprite when the user taps a section.

Could we make those images with alpha channels faster?

[1] https://github.com/mozilla-b2g/gaia/blob/master/apps/settings/style/images/icons_sprite.gif
[2] https://github.com/mozilla-b2g/gaia/blob/master/apps/settings/style/images/icons_sprite_active.gif

Comment 1

[Jeff Muizelaar [:jrmuizel]]

(In reply to Anthony Ricaud (:rik) from comment #0)
> 
> Could we make those images with alpha channels faster?

Can you profile the slow case?

Comment 2

[Anthony Ricaud (:rik)]

I don't have a phone with the proper setup for profiling. But I've prepared a branch that has the alpha images. https://github.com/Rik/gaia/tree/settings-with-alpha-863201

Comment 3

[Ben Turner (not reading bugmail, use the needinfo flag!)]

http://people.mozilla.com/~bgirard/cleopatra/#report=b5343802b9b4e794c15ed2d48380194425855d78

Comment 4

[Sylvestre Ledru [:Sylvestre]]

Mass closing as we are no longer working on b2g/firefox os.

Comment 5

[Sylvestre Ledru [:Sylvestre]]

Mass closing as we are no longer working on b2g/firefox os.