527750 - Fonts are too large when styled using physical sizes

Status: VERIFIED FIXED

(Firefox for Android Graveyard :: General, defect)

Description

[Mark Finkle (:mfinkle) (use needinfo?)]

For some reason the fonts are just way to big. Works fine in microb on N900.

Comment 1

[Mark Finkle (:mfinkle) (use needinfo?)]

Looks horrible on desktop too

Comment 2

[Mark Finkle (:mfinkle) (use needinfo?)]

Removing the body { font-size: 10pt; } fixes the font appearance

Comment 3

[Aakash Desai [:aakashd]]

This is the same on http://blogs.mercurynews.com/kawakami/ and blog.mozilla.com/addons/ I believe.

Comment 4

[Aakash Desai [:aakashd]]

Sorry for the double post, but this should also block fennec I think. Please marking this as blocking-fennec? after bug 528867 is fixed.

Comment 5

[Stuart Parmenter]

amazon.com search area too.

Comment 6

[Mark Finkle (:mfinkle) (use needinfo?)]

A general summary of the problem:

Devices have small screens, but high DPI. So a webpage might fit nicely into the 800px width of the N900/N810 screen. Default fonts are sized using pixels, so the text appears to be scaled appropiately, where "appropriately" means the text is small (maybe even hard to read). The browser allows the webpage to be "zoomed" without reflow so the text can be read.

However, if some text is styled with physical sizes (pt, mm, in), then the platform will try to size the text to the physical dimension. The problem is this: 800px on a 20 inch desktop monitor (96 DPI) means the 16pt (0.22 inches) font might look fine. On the 3.5 inch mobile device (265 DPI), the 16pt (0.22 inches) font looks enormous.

Think of it this way: on a 20 inch monitor, 16pt (0.22 inches) is about 1% of the screen size. On the 3.5 inch mobile device, 16pt (0.22 inches) is about 6% of the screen size.

Everything else being equal (or pixel based in this case), the font difference is out of balance.

Comment 7

[Mark Finkle (:mfinkle) (use needinfo?)]

(In reply to comment #6)
> However, if some text is styled with physical sizes (pt, mm, in), then the
> platform will try to size the text to the physical dimension. The problem is
> this: 800px on a 20 inch desktop monitor (96 DPI) means the 16pt (0.22 inches)
> font might look fine. On the 3.5 inch mobile device (265 DPI), the 16pt (0.22
> inches) font looks enormous.

Even though the fonts are actually the same size on both screens: 0.22 inches is the same everywhere. It's the out-of-balance part that makes the 0.22 inch font now look way too big.

Comment 8

[Mark Finkle (:mfinkle) (use needinfo?)]

fixed by bug 531102 and bug 530931

Comment 9

[Aakash Desai [:aakashd]]

verified FIXED on builds:

Mozilla/5.0 (X11; U; Linux armv7l; Nokia N900; en-US; rv:1.9.2b5pre) Gecko/20091130 Firefox/3.6b5pre Fennec/1.0b6pre

and

Mozilla/5.0 (X11; U; Linux armv6l; Nokia N8xx; en-US; rv:1.9.3a1pre) Gecko/20091130 Firefox/3.7a1pre Fennec/1.0b5

Comment 10

[Aakash Desai [:aakashd]]

We need to create a local test page that includes variations of text sizing mentioned in commet #6 before we can add this testcase to litmus. I'll get to it when I get the chance to do so.

Comment 11

[Martijn Wargers (dead)]

I'm reassigning this to myself for adding litmus testcases for this (aakashd discussed this on irc with blassey and ted on #mobile).