shithub: freetype+ttf2subf

ref: c4f622c3411141e1dfa94813a6c111b67f4f233e
dir: /docs/BUGS/

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List of known FreeType 2 Bugs
-----------------------------

"Identifier" is a unique string used to uniquely identify the bug
A more complete description of the bug is found below the table of
opened bugs..

"Date" is the date where the bug was first reported or entered
in this document. Dates are in _european_ format, i.e day/month/year

"Opened By" is the name of the people who first spotted the bug.
Note that we can use abbreviations here, like:

   "David"  for David Turner
   "Werner" for Werner Lemberg
    etc..

"Reproducable" indicates wether the bug could be reproduced by the
development team or not (it can be specific to a given platform),
wether it always happen, or only sporadically, etc..



I. Opened bugs:
===============

Identifier                Date        Opened by                 Reproducable
------------------------------------------------------------------------------
NO-CID-CMAPS            13-09-2001     David                     always
AUTOHINT-NO-SBITS       13-09-2001     David                     always
BAD-TT-RENDERING        12-09-2001     Paul Pedriana             ?
BAD-THIN-LINES          13-09-2001     David                     ?

--------------------END-OF-OPENED-BUGS-TABLE----------------------------------



II. Table of closed bugs:
=========================

Identifier                Date         Closed by                Closure date
------------------------------------------------------------------------------
BAD-TTNAMEID.H          12-09-2001     Antoine                   N/A


--------------------END-OF-CLOSED-BUGS-TABLE----------------------------------



II. Bug descriptions:
=====================

NO-CID-CMAPS:
   Not exactly a bug, but the CFF font driver doesn't build a Unicode
   charmap from the content of font files, which prevents efficiently
   using fonts in this format..
   
   
BAD-TTNAMEID.H
   the file "ttnameid.h" contains various constant macro definitions
   corresponding to important values defined by the TrueType specification.
   
   Joe Man <[email protected]> reports that:
   
        According to the information from
        TrueType v1.66
        
        Platform ID = 3 (Microsoft)
        the Encoding ID of GB2312 = 4
        the Encoding ID of big5 = 3
        
        However, I have found that 
        in ttnameid.h
        TT_MS_ID_GB2312 = 3
        TT_MS_ID_BIG_5 = 4
        
        Which one is correct?

  Antoine replied that this was a bug in the TT 1.66 specification, and
  that FreeType followed the most recent TrueType/OpenType specification
  here !!
        

AUTOHINT-SBITS
   when trying to load a glyph, with the auto-hinter activated (i.e.
   when using FT_LOAD_FORCE_AUTOHINT, or when the font driver doesn't
   provide its own hinter), embedded bitmaps are _never_ loaded, unlike
   the default behaviour described by the API specification.

   this seems to be a bug in FT_Load_Glyph, but there is no way to solve it
   efficiently without making a few important internal changes to the library's
   design (more importantly, to the font driver interface)
      
   
   
BAD-TT-RENDERING
   according to Paul Pedriana <[email protected]>, there is a rather
   important difference between the rendering of TrueType-hinted glyphs
   of current FT2 and old betas..
   
   Tests and comparisons show a _major_ discrepancy of monochrome truetype
   bytecode-hinted glyphs !! Something seems to be really fucked here !!



BAD-THIN-LINES
   it seems that the anti-aliased renderer in FreeType has problems
   rendering extremely thin straight lines correctly, at least when using
   the FT_Outline_Render functions..