818935 - [HiDPI] Download Manager file icons are disproportionately large

Status: RESOLVED FIXED

(Toolkit :: Downloads API, defect)

Description

[Greg Edwards]

Attachment: Download Manager in 192dpi setup

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:19.0) Gecko/20121204 Firefox/19.0
Build ID: 20121204042015

Steps to reproduce:

Set Windows to a DPI higher than 96.
Download some files.
Open the Download Manager if it isn't already.


Actual results:

Observe that the icons are much bigger relative to font sizes and other UI elements.
(In other words, icon pixel sizes are scaling proportionate to the *square* of the DPI scale.)


Expected results:

Icons should scale proportionately.

I figure icon sizes from Windows are being interpreted as px units instead of device pixels.

Comment 1

[Greg Edwards]

Attachment: 96DPI reference

Comment 2

[Ioana (away)]

Reproduced on the 12/10 Nightly, on Windows 7 64bit.

Comment 3

[Marco Bonardo [:mak]]

This is not the panel

Comment 4

[Felix Miata]

The only problem I see @ 192 is other icons too small.

Comment 5

[Jim Mathies [:jimm]]

Attachment: current screenshot

We need to do a better job of using the appropriate resolution if it is available. We are currently scaling up a lower resolution icon in some cases.

Comment 6

[Jim Mathies [:jimm]]

What do we have to do in these cases? I sense the patch might be a pretty simple moz-icon change, but I'm not sure.

Comment 7

[Jonathan Kew [:jfkthame]]

Attachment: explicitly control the size of icons in the downloaded items list

This is a simple fix, actually. We just need to ensure the icon is always displayed at the proper size (in terms of CSS pixels), so that the larger icons we get on a hidpi system are used to provide better resolution, not simply rendered at a larger physical size (with blurry, upscaled pixels).

Comment 8

[Greg Edwards]

I see this method still producing less-than-perfect results if devPixelsPerPx doesn't match the platform's scale. (But it's a step in the right direction.)
Ideally, Fx would fetch the raw .ico and run it through the new media fragment parser from Bug 419588.

Comment 9

[Jonathan Kew [:jfkthame]]

(In reply to Greg Edwards from comment #8)
> I see this method still producing less-than-perfect results if
> devPixelsPerPx doesn't match the platform's scale.

FWIW, I suspect many things will be less-than-perfect in that scenario. We should be (strongly) discouraging people from messing with devPixelsPerPx, and focus on making the browser work correctly (and look good) by default.

Comment 10

[Jonathan Kew [:jfkthame]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/404e8ab42a22

Comment 11

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/404e8ab42a22