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Infinality 79e36baebb [truetype] Support subpixel hinting.
This is the large, famous `Infinality' patch to support ClearType
bytecode which has been available from
http://www.infinality.net/blog/ for some time, and which has been
refined over the last years.  While still experimental, it is now
mature enough to be included directly into FreeType.

Most of the code is based on the ClearType whitepaper written by
Greg Hitchcock

  http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx

which gives a detailed overview of the necessary changes to the
Microsoft rasterizer so that older fonts are supported.  However, a
lot of details are still missing, and this patches provides a
framework to easily handle rendering issues down to the glyph level
of certain fonts.

Note that ClearType support is not completely implemented!  In
particular, full support for the options `compatible_widths',
`symmetrical_smoothing, and `bgr' (via the GETINFO bytecode
instruction) is missing.

* src/truetype/ttsubpix.c: New file, providing code to handle
`tweaks', this is, rules for certain glyphs in certain fonts
(including wildcards) which need a special treatment.

* src/truetype/ttsubpix.h: New file, holding the tweaking rules.

* include/freetype/config/ftoption.h, src/devel/ftoption.h
(TT_CONFIG_OPTION_SUBPIXEL_HINTING): New macro.

* include/freetype/internal/ftobjs.h (FT_PIX_FLOOR_GRID,
FT_PIX_ROUND_GRID, FT_PIX_CEIL_GRID): New macros.

* src/truetype/truetype.c [TT_USE_BYTECODE_INTERPRETER]: Include
`ttsubpix.c'.

* src/truetype/ttgload.c: Include `ttsubpix.h'.
[All changes below are guarded by TT_CONFIG_OPTION_SUBPIXEL_HINTING.]

(tt_get_metrics): Set tweak flags.
(TT_Hint_Glyph): Call `FT_Outline_EmboldenXY' if necessary.
(TT_Process_Simple_Glyph): Compensate emboldening if necessary.
(compute_glyph_metrics): Handle `compatible widths' option.
(tt_loader_init): Handle ClearType GETINFO information bits.

* src/truetype/rules.mk (TT_DRC_SRC): Updated.

* src/truetype/ttinterp.c: Include `ttsubpix.h'.
[Where necessary, changes below are guarded by
TT_CONFIG_OPTION_SUBPIXEL_HINTING.]

(Direct_Move, Direct_Move_X): Extended.
(Round_None, Round_To_Grid, Round_To_Half_Grid, Round_Down_To_Grid,
Round_Up_To_Grid, Round_To_Double_Grid, Round_Super, Round_Super_45,
SetSuperRound): Add parameter to handle the number of grid lines per
pixel.
(SET_SuperRound, ROUND_None, CUR_Func_round): Updated.
(DO_SROUND, DOS45ROUND, DO_ODD, DO_EVEN): Updated.
(DO_ROUND, DO_NROUND): Updated.
(DO_RS): Take care of `Typeman' bytecode patterns.
(Ins_FDEF): Add some debugging code.  Commented out.
(Ins_ENDF): Restore state.
(Ins_CALL, Ins_LOOPCALL): Handle inline delta functions.
(Ins_MD): Handle `Vacuform' rounds.
(Move_Zp2_Point, Ins_SHPIX, Ins_MSIRP, Ins_MDAP, Ins_MIAP,
Ins_MDRP, Ins_MIRP): Handle tweaks.
(Ins_ALIGNRP): Add tweak guard.
(Ins_IUP, Ins_DELTAP): Handle tweaks.
(Ins_GETINFO): Handle new ClearType bits.
(TT_RunIns): Handle tweaks.

* src/truetype/ttinterp.h: Updated.
(SPH_TweakRule, SPH_ScaleRule): New structures for tweaks.
(TT_ExecContextRec): Add members for subpixel hinting support.

* src/truetype/ttobjs.h (TT_DefRecord): Add `inline_delta' member.
2012-06-18 10:36:06 +02:00
builds * Version 2.4.10 released. 2012-06-15 06:45:12 +02:00
devel [truetype] Support subpixel hinting. 2012-06-18 10:36:06 +02:00
docs * Version 2.4.10 released. 2012-06-15 06:45:12 +02:00
include [truetype] Support subpixel hinting. 2012-06-18 10:36:06 +02:00
objs Ignore *.o and *.a files. 2011-03-20 18:28:31 +01:00
src [truetype] Support subpixel hinting. 2012-06-18 10:36:06 +02:00
.gitignore We no longer use CVS. 2010-01-23 16:19:33 +01:00
ChangeLog [truetype] Support subpixel hinting. 2012-06-18 10:36:06 +02:00
ChangeLog.20 Add one more example to the documentation of FT_Glyph_To_Bitmap. 2008-08-06 09:09:41 +00:00
ChangeLog.21 Formatting, copyright years. 2008-07-27 06:27:21 +00:00
ChangeLog.22 Formatting, copyright years. 2008-07-27 06:27:21 +00:00
ChangeLog.23 Fix ChangeLogs. 2010-08-29 06:04:51 +09:00
Jamfile * Version 2.4.10 released. 2012-06-15 06:45:12 +02:00
Jamrules Add license. 2005-06-04 23:04:30 +00:00
Makefile * Makefile, *.mk: Use `?=' where appropriate. 2006-02-01 07:52:11 +00:00
README * Version 2.4.10 released. 2012-06-15 06:45:12 +02:00
README.git Typo. 2010-07-12 21:25:01 +02:00
autogen.sh Set the executable bit of autogen.sh. 2011-11-29 23:56:23 +01:00
configure Whitespace. 2011-12-02 20:22:04 +01:00
modules.cfg Add new error code FT_Err_Missing_Module. 2011-11-26 13:38:26 +01:00
version.sed Put version information into the configure script. Reported by Paul 2006-05-08 07:10:29 +00:00
vms_make.com typo 2007-02-12 14:35:15 +00:00

README

  FreeType 2.4.10
  ===============

  Please   read   the  docs/CHANGES   file,   it  contains   IMPORTANT
  INFORMATION.

  Read the files `docs/INSTALL' for installation instructions.

  See the  file `docs/LICENSE.TXT'  for the available licenses.   Note
  that we use ranges (`2008-2010') for copyright years also instead of
  listing individual years (`2008, 2009, 2010').

  The FreeType 2 API reference is located in `docs/reference'; use the
  file   `ft2-doc.html'   as   the   top  entry   point.    Additional
  documentation is available as a separate package from our sites.  Go
  to

    http://download.savannah.gnu.org/releases/freetype/

  and download one of the following files.

    freetype-doc-2.4.10.tar.bz2
    freetype-doc-2.4.10.tar.gz
    ftdoc2410.zip


  Bugs
  ====

  Please report bugs  by e-mail to `freetype-devel@nongnu.org'.  Don't
  forget to  send a  detailed explanation of  the problem --  there is
  nothing  worse than  receiving a  terse message  that only  says `it
  doesn't work'.

  Alternatively, you may submit a bug report at

    https://savannah.nongnu.org/bugs/?group=freetype


  Enjoy!


    The FreeType Team

----------------------------------------------------------------------

Copyright 2006-2011 by
David Turner, Robert Wilhelm, and Werner Lemberg.

This  file is  part of  the FreeType  project, and  may only  be used,
modified,  and distributed  under the  terms of  the  FreeType project
license,  LICENSE.TXT.  By  continuing to  use, modify,  or distribute
this file you  indicate that you have read  the license and understand
and accept it fully.


--- end of README ---