589983 - Avoid using svg-mask in the back button in the windows theme

Status: RESOLVED DUPLICATE of bug 752918

(Firefox :: Theme, defect)

Description

[Jeff Muizelaar [:jrmuizel]]

The use of mask in the back button is currently costly to implement with the D2D backend. I don't have any actual numbers but the cost is unfortunately proportional to the size of the entire window and any work to improve this has not been scoped for Firefox 4.

I'm wondering how painful it would be to avoid using mask and just use images instead.

Comment 1

[Robert O'Callahan (:roc) (email my personal email if necessary)]

(In reply to comment #0)
> The use of mask in the back button is currently costly to implement with the
> D2D backend. I don't have any actual numbers but the cost is unfortunately
> proportional to the size of the entire window and any work to improve this has
> not been scoped for Firefox 4.

What's the problem, specifically?

Comment 2

[Jeff Muizelaar [:jrmuizel]]

(In reply to comment #1)
> (In reply to comment #0)
> > The use of mask in the back button is currently costly to implement with the
> > D2D backend. I don't have any actual numbers but the cost is unfortunately
> > proportional to the size of the entire window and any work to improve this has
> > not been scoped for Firefox 4.
> 
> What's the problem, specifically?

acquire_source_image doesn't know how much of the source will be needed so it gets the whole source.

Comment 3

[Jeff Muizelaar [:jrmuizel]]

(In reply to comment #0)
> I don't have any actual numbers but the cost is unfortunately
> proportional to the size of the entire window and any work to improve this has
> not been scoped for Firefox 4.

I just realized something doesn't make sense here. I'll double check tomorrow.

Comment 4

[:Gavin Sharp [email: [e-mail]]]

There are no more svg-masks in any Firefox theme (since bug 752918).