335076 - [BeOS] Wrong rendering of point-sized font tags

Status: RESOLVED FIXED

(Core Graveyard :: GFX: BeOS, defect)

Description

[Sergei Dolgov]

This problem started to be visible after 
https://bugzilla.mozilla.org/show_bug.cgi?id=327406
checkin.
Two users noticed it with dualhead setup, so virtual screen size was 2560 * 1024.
http://beos.spb.ru/mozilla/MozillaFontPointSizeBug2.png - look at counter at
bottom.
But it should be noticeable with single moder big monitors too, so i'm wondering if someone has 1960*1200 or such monitor here.

Problem is lack of DPI API (and DPI-awarness at all) in BeOS, so we use some tricks here
http://lxr.mozilla.org/seamonkey/source/gfx/src/beos/nsDeviceContextBeOS.cpp#136

but it seems that following code is also not so perfect.

As possible fixes and workarounds i propose
1)add "layout.css.dpi" also to BeOS section of all.js
2)restrict max resolution unconditionally to some valuse in nsDeviceContext - but what that value should be?
72 (this is DPI with which BeOS was designed in mind) produces too small fonts) ?
96?
Looks like it needs testing
3)that hack in source code before - I propose int(mHeightFloat*72./600.);
instead. As hardly someone will set dualhead to increase vertical resolution - it is hard to imagine monitors on top of eachother. Even Bill Gates don't do it with his 3 monitors!

4)Currently we always report single monitor in ScreenManager:
NS_IMETHODIMP
nsScreenManagerBeOS :: GetNumberOfScreens(PRUint32 *aNumberOfScreens)
{
  *aNumberOfScreens = 1;
  return NS_OK;
}
Looks like times are changing, but I'm doubt that there is good piblic BeOS API to handle this poblem

Comment 1

[Sergei Dolgov]

Attachment: screenshot for bug URL

screenshot of haiku CIA

Comment 2

[tqh]

Do you know anything more about why the fonts are to small at 72dpi?

I suspect I might be of little help in fixing this though.

Comment 3

[Sergei Dolgov]

I fount that res somewhere between 84 and 88 is optimal.
And it is approximate DPI for 15" 1024*x and 19" 1280*x and 20" 1680*x monitors.

Comment 4

[Sergei Dolgov]

I think we will use fixed OSDpi value instead that fake-calculated, after getting more feedback from users.

Comment 5

[Sergei Dolgov]

Attachment: patch

adding "layout.css.dpi" to BeOS section of all.js

Comment 6

[Sergei Dolgov]

Attachment: patch

Setting fixed average value (85) as OSVal for Dpi.

Comment 7

[tqh]

Comment on attachment 220240 [details] [diff] [review]
patch

r=[e-mail]

This workaround is ok by me, I assume you have tested this on a few different setups already from what I can understand.

Comment 8

[Sergei Dolgov]

Comment on attachment 220240 [details] [diff] [review]
patch

as this is change inside common for all platforms file, i think it needs second review

Comment 9

[Sergei Dolgov]

Checking in mozilla/gfx/src/beos/nsDeviceContextBeOS.cpp;
/cvsroot/mozilla/gfx/src/beos/nsDeviceContextBeOS.cpp,v  <--  nsDeviceContextBeOS.cpp
new revision: 1.34; previous revision: 1.33
done 

Comment 10

[Sergei Dolgov]

Checking in mozilla/modules/libpref/src/init/all.js;
/cvsroot/mozilla/modules/libpref/src/init/all.js,v  <--  all.js
new revision: 3.635; previous revision: 3.634
done

Comment 11

[Niels Reedijk]

Going to land in the branch.

Comment 12

[Niels Reedijk]

Comment on attachment 220240 [details] [diff] [review]
patch

Requesting permission to land in the MOZILLA_1_8_BRANCH.

This is a BeOS-only change and does not affect other platforms.

Note: sergei_d: Apply after bug 316305.

Comment 13

[Niels Reedijk]

Comment on attachment 220241 [details] [diff] [review]
patch

Requesting permission to land in the MOZILLA_1_8_BRANCH.

This is a BeOS-only change. Testing on the trunk showed that no other platforms were affected.

Note: sergei_d: second and last patch on this bug.

Comment 14

[Mike Beltzner [:beltzner, not reading bugmail]]

Comment on attachment 220241 [details] [diff] [review]
patch

a=drivers, BeOS the TheOS! :)

Comment 15

[Sergei Dolgov]

Checking in mozilla/gfx/src/beos/nsDeviceContextBeOS.cpp;
/cvsroot/mozilla/gfx/src/beos/nsDeviceContextBeOS.cpp,v  <--  nsDeviceContextBeOS.cpp
new revision: 1.31.8.2; previous revision: 1.31.8.1
done
Checking in mozilla/modules/libpref/src/init/all.js;
/cvsroot/mozilla/modules/libpref/src/init/all.js,v  <--  all.js
new revision: 3.585.2.48; previous revision: 3.585.2.47
done