bugThe FreeType Project - Bugs: bug #28021, Strictly aligned text rendered...

 
 

bug #28021: Strictly aligned text rendered irregular in several mono-width fonts, please see the attachment.

Submitted by:  Igor M Podlesny <poige>
Submitted on:  Sun 15 Nov 2009 07:19:59 AM UTC  
 
Severity: 3 - NormalItem Group: Incorrect behaviour
Status: FixedPrivacy: Public
Assigned to: Werner LEMBERG <wl>Open/Closed: Closed
Planned Release: 2.3.12

Add a New Comment(Rich Markup)
   

You are not logged in

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

 

(Jump to the original submission Jump to the original submission)

Mon 16 Nov 2009 02:15:41 PM UTC, comment #14:

Basically, you are correct. However, only the autohinter is
affected; using the native TrueType bytecode interpreter, you
won't see any problems.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Mon 16 Nov 2009 08:06:15 AM UTC, comment #13:

Thank you. So can we conclude it in this way(?) -- there wasn't such problem in Freetype2 at all, and the screenshot I had attached reflected just those two font's bugs.

Igor M Podlesny <poige>
Mon 16 Nov 2009 08:01:02 AM UTC, comment #12:

It's exactly the same problem. FontForge determines automatically
whether it is a fixed-width font – all glyphs which contain
outlines are taken into account. For example, in
LiberationMono-Regular.ttf, the .notdef glyph has a different
width than all others, which I consider a bug. If you fix this,
the isFixedPitch flag is correctly set (I've just tried that,
BTW).

You should report it to the font maintainers...

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Mon 16 Nov 2009 07:02:12 AM UTC, comment #11:

> if you have a buggy font, you get a buggy result.


It's clearly understood (actually, that's why I said "I'm not fully sure it's freetype2's bug." in the original bug submission).

Well, "Monaco_Linux" is quite easy to suppose to be buggy, but what about RedHat's "Liberation Mono" ( http://en.wikipedia.org/wiki/Liberation_fonts )?

Igor M Podlesny <poige>
Mon 16 Nov 2009 06:26:41 AM UTC, comment #10:

I have two older versions of `Monaco' (version 1.0 from 1997 and
version 4.1d3 from 2003-09-16). Monaco_Linux.ttf which I've
found at

http://www.gringod.com/wp-upload/software/Fonts/Monaco_Linux.ttf

is version 5.1d1e1 (from 2005-05-18); contrary to the other
two versions it contains some embedded bitmaps, but this is of
no importance here.

The very problem of this font is that it doesn't identify itself
as fixed-width: The `isFixedPitch' flag in the `post' table is
not set, which I consider a bug. Consequently, this means that
the autohinter has no clue that it must not change the widths of
the glyphs. I've recently added some code (and fixed due to
your bug report) to assure that the widths of the digits don't
get changed by the autohinter if they are all the same.
However, FreeType doesn't check the whole font for this
property – if you have a buggy font, you get a buggy result.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sun 15 Nov 2009 03:43:18 PM UTC, comment #9:

+ May be it worth mentioning that I don't use TT_CONFIG_OPTION_BYTECODE_INTERPRETER.

Also, what do you think -- should I try applying not only that patch, but rather use all changes in git since 2.3.11?

Igor M Podlesny <poige>
Sun 15 Nov 2009 03:36:35 PM UTC, comment #8:

Try testing "Monaco", 12 (DPI 96^2). BTW, which Monaco do you use? I have one named Monaco_Linux, IIRC. You can also try using Liberation Mono, it's just the same artifacts.

> Are you sure that you have replaced the FreeType library


Yes, verified.

Igor M Podlesny <poige>
Sun 15 Nov 2009 03:11:23 PM UTC, comment #7:

It works for me; I've tested with ftview: The Monaco font now
shows equal width for all digits after pressing the `f' key to
force autohinting. For my tests I use `make devel' which creates
a static library which then gets linked into the ftdemo programs.
This assures that I can't use the wrong library version.

Are you sure that you have replaced the FreeType library
correctly (or using a proper LD_LIBRARY_PATH environment
variable)?

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sun 15 Nov 2009 11:52:25 AM UTC, comment #6:

I've tried patch "7635ba64", alas -- the problem remains...

Igor M Podlesny <poige>
Sun 15 Nov 2009 10:16:38 AM UTC, comment #5:

The Savannah admins know about this problem – I've reported it about half a year ago. Apparently, nothing has improved meanwhile. I've sent them a reminder email right now.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sun 15 Nov 2009 10:03:56 AM UTC, comment #4:

Thanks!

I had tried cloning git-repo, cause it's not clear how to use searching for commit @ WEB-source browser:

$ git clone git://git.savannah.nongnu.org/freetype.git
Initialized empty Git repository in /tmp/free/freetype/.git/
warning: You appear to have cloned an empty repository.

Eventually, I've found it should be like that:

git clone git://git.savannah.nongnu.org/freetype/freetype2.git/

So, if I'm right, it's better having https://savannah.nongnu.org/git/?group=freetype corrected.

Igor M Podlesny <poige>
Sun 15 Nov 2009 09:48:42 AM UTC, comment #3:

It's commit 7635ba64.

And no, #25392 hasn't been fixed yet. David apparently no longer
works on FreeType, and I don't have enough time currently to
learn the intricate details of auto hinting.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sun 15 Nov 2009 09:28:55 AM UTC, comment #2:

I see, well, Ok, I'll try to give it a test. BTW, is there any specific commit in the git-repo, so I could just apply the patch?

P. S. Haven't been https://savannah.nongnu.org/bugs/?25392 also fixed already, by any chance? :-)

Igor M Podlesny <poige>
Sun 15 Nov 2009 09:19:54 AM UTC, comment #1:

How embarassing :-) This should have been fixed already, but
a loop was faulty. Fixed now in git. Please test!

Thanks for the report.

Werner LEMBERG <wl>
Project AdministratorIn charge of this item.
Sun 15 Nov 2009 07:19:59 AM UTC, original submission:

Irregularity in this example happened for "Monaco", but not for "Consolas". The same irregularity noticed with "Liberation Mono".

freetype2 ver.: 2.3.11 (2.3.9 also had this)

P. S. I'm not fully sure it's freetype2's bug.

Igor M Podlesny <poige>

 

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

Attach File(s):
   
   
Comment:
   

Attached Files
file #19055:  irregular.png added by poige (215KiB - image/png - "Consolas" -- fine, but not "Monaco".)

 

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 poige (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 5 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Sun 15 Nov 2009 09:19:54 AM UTCwlStatusNone=>Fixed
      Assigned toNone=>wl
      Open/ClosedOpen=>Closed
      Planned ReleaseNone=>2.3.12
    Sun 15 Nov 2009 07:19:59 AM UTCpoigeAttached File-=>Added irregular.png, #19055

    Back to the top


    Powered by Savane 3.1-cleanup1