[cairo] rotated characters does not keep baseline

[Jan Slupski]

On Wed, 4 Apr 2007, Behdad Esfahbod wrote:

> On Wed, 2007-04-04 at 12:47 -0400, Jan Slupski wrote:
>> Hi list,
>>
>> Since 1.4 rush seems to slow down, I would like to bring back
>> a few issues reported before 1.4.0.
>>
>> Problem:
>> (http://lists.freedesktop.org/archives/cairo/2007-February/009686.html)
>>
>> 2. I'm trying to force metrics hinting to be OFF for rotated text
>>      (correct me, but I think that should be default?), but it seems
>>      that some kind of hinting is still applied (or maybe that's some
>>      cache effect?)
>
> This bug was fixed in 1.4.2
>
>
>>      On attached picture you can see that letters are not layed out
>>      on the same baseline.
>>
>>      Also, looking closely (zoom x8) I noticed that shapes of all
>>      same letters looks identically (although they are not necessairly
>>      on the same basline - compare 'l' in "display" and 'l' in "angle").
>>
>>      The same string with the same font at the same angle look way better
>>      at bare FreeType.
>>
>>      ftstring  -m "Hello this is long text to be display at some angle" 10 times.ttf
>>
>>      and rotate with right cursor until 45 degrees.
>>
>> My configuration:
>>     Cairo version: 1.3.14
>>     freetype-2.2.1-16
>>     fontconfig-2.4.1-3
>>
>>
>> ***UPDATE***:
>>    Tested with cairo 1.4.2
>>    Use test string "iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii" to easily see the problem.
>>
>>    During some (unrelated directly) discussions on the list I have learned that
>>    the effect can be due to glyph cache, that stores only single image of a letter
>>    that is later reused.  This seems to be wrong in any (metrics-)unhinted mode
>>    (rotated or not).
>
> True.  We don't have a plan to fix it right now.  Any ideas?

Add to TODO list?  ;-)

Jan

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    | |_| |\ |  S L U P S K I             jslupski at juljas.net
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