Suggested by Doug Felt <dougfelt@gmail.com>.
* src/sfnt/ttsbit.c (tt_sbit_decoder_load_metrics): Set
`vertAdvance' to zero...
* src/truetype/ttgload.c (TT_Load_Glyph): ... and set here a default
value for `vertAdvance' based on `linearVertAdvance' in case
`vertAdvance' is zero. Note that the previous computed ad-hoc value
for `linearVertAdvance' was apparently not tested in a real-life
situation.
The legal range for delta shift is zero through six. Negative values
are illegal according to
https://developer.apple.com/fonts/TrueType-Reference-Manual/RM04/Chap4.html#delta%20shift
* src/truetype/ttobjs.h (delta_shift, delta_base): Make unsigned.
* src/truetype/ttinterp.h (DO_SDS): Throw an error if delta_shift
out of range.
(Ins_DELTAP, Ins_DELTAC): Optimize for legal delta_shift.
We shift as many bits as we can into the high register, perform
32-bit division with modulo there, then work through the remaining
bits with long division. This optimization is especially noticeable
for smaller dividends that barely use the high register.
* src/base/ftcalc.c (ft_div64by32): Updated.
This applies to `FT_MulDiv' but not to `FT_DivFix', where overflows or
lack thereof are predicted accurately.
* src/base/ftcalc.c (ft_div64by32): Improve readability.
(FT_MulDiv, FT_MulDiv_No_Round) [!FT_LONG64]: Use straight division
when multiplication stayed within 32 bits.
This fixes a 13-year old bug. The original overflow check should have
been updated when rounding was introduced into this function
(c2cd00443b).
* src/base/ftcalc.c (FT_DivFix) [!FT_LONG64]: Updated.
* include/freetype.h (FT_DivFix): Updated documentation.
* src/truetype/ttinterp.h (TT_ExecContextRec): New field
`cur_ppem_func' with a function pointer.
* src/truetype/ttinterp.c (TT_RunIns): Initialize `cur_ppem_func'
depending on the pixel geometry to either...
(Current_Ppem_Stretched): ... this for stretched pixels.
(Current_Ppem): ... or this for square pixels.
(DO_MPPEM, DO_MPS, Ins_DELTAP, Ins_DELTAC): Use `cur_ppem_func'.
* include/freetype.h (FT_MulFix): Unconditionally defined.
* src/base/ftcalc.c [FT_MULFIX_ASSEMBLER]: Move code from here...
* include/internal/ftcalc.h [FT_MULFIX_ASSEMBLER]: ... to here,
which conditionally replaces the function with an inline version
through the macro.
* src/pfr/pfrobjs.c (pfr_face_get_kerning): Use `FT_MSB' instead of
`ft_highpow2'.
* src/base/ftutil.c, include/internal/ftobjs.h (ft_highpow2): Remove
it.
Werner Lemberg
Alexei Podtelezhnikov
David Weiß
Dave Arnold
Behdad Esfahbod