bugThe FreeType Project - Bugs: bug #34507, Distorted fonts after 2.4.4 to...

 
 

bug #34507: Distorted fonts after 2.4.4 to 2.4.6 upgrade

Submitted by:  Marek Kozłowski <guayasil>
Submitted on:  Sat 08 Oct 2011 05:04:03 PM UTC  
 
Severity: 3 - NormalItem Group: Incorrect behaviour
Status: DuplicatePrivacy: Public
Assigned to: Werner LEMBERG <wl>Open/Closed: Closed
Planned Release: None

Add a New Comment (Rich MarkupRich Markup):
   

You are not logged in

Please log in, so followups can be emailed to you.

 

Mon 10 Oct 2011 06:32:05 AM UTC, comment #3:

Essentially, it's the same problem. Version 2.4.6 has added this important line (file truetype/ttdriver.c, at the end of function tt_size_request) which was missing in previous versions:

ttsize->root.metrics = ttsize->metrics;

This copies the freshly calculated TrueType metrics into the root structure. For example, if you debug `ftdiff -r 120 verdana.ttf', you get

(gdb) p *metrics
$8 = {
x_ppem = 27,
y_ppem = 27,
x_scale = 54624,
y_scale = 54624,
ascender = 1728,
descender = -384,
height = 2048,
max_advance = 2624
}

with version 2.4.4, and

(gdb) p *metrics
$8 = {
x_ppem = 27,
y_ppem = 27,
x_scale = 55296,
y_scale = 55296,
ascender = 1728,
descender = -384,
height = 2112,
max_advance = 2624
}

with 2.4.6; without the copying, the specially computed TrueType values are not properly propagated to the top-level. In particular, the TrueType specification asks for rounding of (some) metrics values, while FreeType by default uses flooring and ceiling.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sun 09 Oct 2011 06:00:50 PM UTC, comment #2:

But those bug reports concern monospace and dejavu fonts. I experience it with other fonts including, for example, Verdana (used on attached pictures)...
BTW: my desktop is XFCE, I'm using custom resolution of 120 DPI.

Marek Kozłowski <guayasil>
Sat 08 Oct 2011 09:43:44 PM UTC, comment #1:

Please read bug reports #33939 and #34156; I'm quite sure that one of the two problems is affecting you.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sat 08 Oct 2011 05:04:03 PM UTC, original submission:

An excerpt from my config:

<match target="font" >
<edit mode="assign" name="rgba" <const>rgb</const</edit>
<edit mode="assign" name="hinting" ><bool>true</bool></edit>
<edit mode="assign" name="autohint" ><bool>false</bool></edit>
<edit mode="assign" name="antialias" ><bool>true</bool></edit>
<edit mode="assign" name="hintstyle" ><const>hintslight</const></edit>
<edit name="lcdfilter" mode="assign"><const>lcddefault</const></edit>
</match>

I described the bug in Arch bugzilla although the same bug persists under Gentoo:

https://bugs.archlinux.org/task/25333

Especially you can compare the screenshots attached to that bug report:

2.4.4:
https://bugs.archlinux.org/task/25333?getfile=7584
https://bugs.archlinux.org/task/25333?getfile=7585

2.4.6
https://bugs.archlinux.org/task/25333?getfile=7586
https://bugs.archlinux.org/task/25333?getfile=7587

Wrong proportion lead to some deformation of the fonts.

Marek Kozłowski <guayasil>

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach File(s):
   
   
Comment:
   

No files currently attached

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -unavailable- added by wl (Posted a comment)
  • -unavailable- added by guayasil (Submitted the item)
  •  

    Do you think this task is very important?
    If so, you can click here to add your encouragement to it.
    This task has 0 encouragements so far.

    Only logged-in users can vote.

     

    Please enter the title of George Orwell's famous dystopian book (it's a date):

     

     

    Follow 4 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Mon 10 Oct 2011 06:32:05 AM UTCwlStatusNeed Info=>Duplicate
      Open/ClosedOpen=>Closed
    Sat 08 Oct 2011 09:43:44 PM UTCwlStatusNone=>Need Info
      Assigned toNone=>wl

    Back to the top


    Powered by Savane 3.1-cleanup