[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.
[cff] Fix Savannah bug #36705.

Handle numbers like 2.001 correctly.

* src/cff/cffparse.c (cff_parse_real): Avoid negative values for
`shift'.
[truetype] Remove unused rounding functionality.
Fix conditional compilation.

* include/freetype/internal/ftcalc.h (FT_MulDiv_No_Round): Don't
enclose with `TT_USE_BYTECODE_INTERPRETER'; we now need the function
elsewhere also.

* src/autofit/afcjk.h: Use AF_CONFIG_OPTION_CJK.

* src/truetype/ttgload.c (tt_loader_init): Fix compiler warning.

* src/truetype/ttinterp.c (Ins_MSIRP): Fix compiler warning.

* src/truetype/ttinterp.h: Use
TT_CONFIG_OPTION_BYTECODE_INTERPRETER.
Fix conditional compilation.

* src/base/basepic.c: Use FT_CONFIG_OPTION_MAC_FONTS.
[truetype] Set the `subpixel_positioned' flag unconditionally.

This is how the code currently behaves.

* src/truetype/ttgload.c (tt_loader_init): Do it.
Fix CFLAGS and LDFLAGS share configure test.

* builds/unix/configure.raw: Fix typo.
[truetype] Fix various artifacts.
Fix `checking if gcc static flag -static works' test.

On my linux build tree, I receive yes answer in in every package I
build except freetype for this test checking if gcc static flag
`-static' works

On freetype, no is received, unless bzip2 and zlib are disabled using

  ./configure --without-bzip2 --without-zlib

The reason is that bzip2 and zlib tests add `-lz' and `-lbz2' to
LDFLAGS and this broke static flag test.

* builds/unix/configure.raw: Update CFLAGS and LDFLAGS only after
LT_INIT has run.
[autofit] Minor speed-up.

* src/autofit/afangles (af_sort_pos, af_sort_widths): Don't swap
elements if they are equal.
[autofit] Quantize stem widths.

* src/autofit/afangles.c (af_sort_widths): Rename to...
(af_sort_and_quantize_widths): This.
Add code to avoid stem widths which are almost identical.
* src/autofit/aftypes.h, src/autofit/aflatin.c, src/autofit/afcjk.c:
Updated.
[autofit] Beautify blue zone tracing.

* src/autofit/aflatin.c (af_latin_metrics_init_blues),
src/autofit/aflatin2.c (af_latin2_metrics_init_blues): Implement it.
[autofit] Improve comment.
Fix Savannah bug #36091.

* src/autofit/aflatin.c (af_latin_metrics_init_blues),
src/autofit/aflatin2.c (af_latin2_metrics_init_blues): Change the
constraint for testing round vs. flat segment: Accept either a
small distance or a small angle.
[autofit] Improve output of debugging information.

* src/autofit/afhints.c (af_glyph_hints_dump_segments): Print more
data; report no data.
(af_glyph_hints_dump_edges): Report no data.
[autofit] Do some code cleanup.

* src/autofit/afglobal.c (af_face_globals_new): Simplify.

* src/autofit/afhints.c: Use `FT_TRACE7' instead of `printf'
everywhere.
(FT_COMPONENT): New macro.
(af_glyph_hints_done): Simplify.

* include/freetype/internal/fttrace.h: Updated.
[ARM] Fix FT_MulFix_arm.

* include/freetype/config/ftconfig.h (FT_MulFix_arm) [__arm__]:
Avoid ADDS instruction to clobber condition codes.
Fix strict-aliasing warning.

* src/base/ftglyph.c (FT_Glyph_To_Bitmap): Avoid double cast.
[autofit] Improve debugging messages; do some code cleanup.

* src/autofit/aflatin.c (af_latin_align_linked_edge,
af_latin_hint_edges): Synchronize with formatting used in the
ttfautohint project.
Fix compilation with MSVC 5.0.

Problem reported by Peter Breitenlohner and Akira Kakuto.

* include/freetype/config/ftstdlib.h (ft_setjmp): Updated.
* src/sfnt/ttcmap.c (tt_face_build_cmaps): Remove cast.