Under normal circumstances we are usually close to the desired range
of angle values, so that the remainder is not really necessary.
* src/base/fttrigon.c (FT_Angle_Diff): Use loops instead of remainder.
* src/autofit/aftypes.h (AF_ANGLE_DIFF): Ditto in the unused macro.
`API functions' are functions tagged with `FT_EXPORT_DEF'.
Besides trivial fixes, the following changes are included, too.
* src/base/ftbdf.c (FT_Get_BDF_Charset_ID, FT_Get_BDF_Property): Set
error code if no service is available.
* src/base/ftinit.c (FT_Done_FreeType): Change return value for
invalid `library' parameter to `Invalid_Library_Handle'.
* src/base/ftobjs.c (FT_New_Size): Change return value for invalid
`asize' parameter to `Invalid_Argument'.
* src/base/ftoutln.c (FT_Outline_Copy): Change return value for
invalid `source' and `target' parameters to `Invalid_Outline'.
(FT_Outline_Done_Internal): Change return value for invalid
`outline' parameter to `Invalid_Outline'.
The scaling between the hypotenuse and its CORDIC approximation is
based on regression analysis. The smaller padding for `theta' is
justifed by its maximum error of less than 6.
* src/base/fttrigon.c (ft_trig_downscale): Borrow code from
./ftcalc.c (ft_multo64), change linear intercept.
(ft_trig_pseudo_polarize): Decrease `theta' padding.
* src/base/ftcalc.c (FT_DivFix): Use unsigned values for
computations which use the left shift operator and convert to signed
as the last step.
* src/base/fttrigon.c (ft_trig_prenorm, FT_Vector_Rotate,
FT_Vector_Length, FT_Vector_Polarize): Ditto.
* src/cff/cffgload.c (cff_decoder_parse_charstrings): Simplify.
* src/cff/cffload.c (cff_subfont_load): Fix constant.
* src/cff/cffparse.c (cff_parse_integer, cff_parse_real, do_fixed,
cff_parse_fixed_dynamic): Use unsigned values for computations which
use the left shift operator and convert to signed as the last step.
* src/cid/cidload.c (cid_get_offset): Ditto.
* src/psaux/psconv.c (PS_Conv_ToFixed): Ditto.
* src/psaux/t1decode.c (t1_decoder_parse_charstrings): Ditto.
* src/truetype/ttinterp.c (TT_MulFix14, TT_DotFix14): Ditto.
* include/freetype/fttrigon.h (FT_Hypot): Declare it.
* src/base/fttrigon.c (FT_Hypot): Define it.
* src/truetype/ttgload.c (TT_Process_Composite_Component): Use it
instead of explicit expressions.
* src/truetype/ttinterp.c (Current_Ratio, Normalize): Use it instead
of TT_VecLen.
(TT_VecLen): Removed.
The recent optimizations of CORDIC iterations drastically reduce
the expansion factor. The vector components with MSB of 29 are now
safe from overflow.
* src/base/fttrigon.c (FT_TRIG_SAFE_MSB): New macro.
(ft_trig_prenorm): Use it and remove dead code.
* src/base/fttrigon.c: Document the algorithm in a large comment.
(FT_TRIG_COSCALE): Remove macro.
(FT_Tan: Use `FT_TRIG_SCALE' instead.
(FT_Cos, FT_Vector_Unit): Ditto and round the return values.
After we get within 45 degrees by means of true 90-degree rotations,
we can remove initial 45-degree CORDIC iteration and start from
atan(1/2) pseudorotation, reducing expansion factor thereby.
* src/base/fttrigon.c (FT_TRIG_SCALE, FT_TRIG_COSCALE): Update macros.
(ft_trig_pseudo_rotate, ft_trig_pseudo_polarize): Update.
* src/tools/cordic.py: Bring up to date with trigonometric core.
* docs/CHANGES: Old typo.
FreeType used to rely on a 24-step iteration CORDIC algorithm to
calculate trigonometric functions and rotate vectors. It turns out
that once the vector is in the right half-plane, the initial rotation
by 63 degrees is not necessary. The algorithm is perfectly capable
to converge to any angle starting from the second 45 degree rotation.
This patch removes the first rotation and makes it a 23-step CORDIC
algorithm.
* src/base/fttrigon.c (FT_TRIG_SCALE, FT_TRIG_COSCALE): Update macro
values.
(ft_trig_pseudo_rotate, ft_trig_pseudo_polarize): Remove initial
rotation.
Since the initial commit (ebe85f59) the value of FT_TRIG_SCALE has
always been slightly less than the correct value, which has been
given in the comment as a hexadecimal. As a result, vector lengths
were underestimated and rotated vectors were shortened.
invalid computations, resulting in very weird bugs in TrueType
bytecode hinted fonts
* src/truetype/ttinterp.c: redefined FT_UNUSED_EXEC to not perform
a structure copy each time. Wooot. !
- fixing apinames.c, adding support for Watcom and Borland compilers
- adding generation of exported symbols list to the build system, including the Unix one !!
sorry Werner, I have no time to document this in ChangeLog at the moment
* src/autofit/*: Add copyright messages.
Formatting.
* src/autofit/afhints.c (af_glyph_hints_done): Don't use
`AF_Dimension' but `int' for loop counter.
* src/autofit/aflatin.c (af_latin_metrics_init_widths): Don't use
`AF_Dimension' but `int' for loop counter.
Use proper enumeration value for `render_mode'.
(af_latin_metrics_scale_dim): Don't shadow variables.
(af_latin_hints_compute_segments): Use proper cast for `major_dir'
and `segment_dir'.
(af_latin_align_linked_edge, af_latin_hint_edges): Fix arguments of call to
`af_latin_compute_stem_width'.
(af_latin_hints_apply): Don't use `AF_Dimension' but `int' for loop
counter.
* src/base/ftdbgmem.c (ft_mem_table_get_source, FT_DumpMemory): Use
proper cast for memory allocation.
* src/cff/cffdrivr.c (cff_get_kerning): Use proper cast for
initialization of `sfnt'.
* src/sfnt/sfdriver.c: Include `ttkern.h'.
* src/sfnt/ttkern.c (tt_face_get_kerning): Don't shadow variables.
* src/truetype/ttgload.c: Include `ttpload.h'.
* src/truetype/ttpload.c (tt_face_load_loca) [FT_OPTIMIZE_MEMORY]:
Remove redundant variable.
FT_INTERNAL_OBJECTS_H.
* src/base/ftstroke.c (FT_Outline_GetInsideBorder,
FT_Outline_GetOutsideBorder): s/or/o/ to make it compile with
C++ compilers.
* src/cache/ftcmru.c, include/freetype/cache/ftcmru.h:
s/select/selection/ to avoid compiler warning.
* src/cff/cffload.h: s/select/ftselect/ to avoid potential
compiler warning.
Formatting.
the API is likely to change however.
* src/base/fttrigon.c (FT_Angle_Diff): fixing function, it returned
invalid values for large negative angle differences (resulting in
incorrect stroker computations, among other things)
* src/cache/ftccache.c (ftc_node_unlink): removing incorrect
assertion, and changing code to avoid hash table size contraction
* src/base/Jamfile, src/base/rules.mk, src/base/descrip.mms:
adding "ftstroker.obj" to default build, as optional component
Werner Lemberg