It turns out that there is significant cost associated with `FT_Span'
creation and calls to `gray_render_span' because it happerns so
frequently. This removes these steps from our internal use but leaves
it alone for `FT_RASTER_FLAG_DIRECT" to preserve API. The speed gain
is about 5%.
* src/smooth/ftgrays.c (gray_render_span): Removed. The code is
migrated to...
(gray_hline): ... here.
Zero coverage is unlikely (1 out of 256) to warrant checking. This
gives 0.5% speed improvement in dendering simple glyphs.
* src/smooth/ftgrays.c (gray_hline, gray_render_span): Remove checks.
This gives 2% speed improvement in rendering simple glyphs.
* src/smooth/ftgrays.c (TPixmap): Reduced pixmap descriptor with a
pointer to its bottom-left and pitch to be used in...
(gray_TWorker): ... here.
(gray_render_span): Move pixmap flow check from here...
(gray_raster_render): .. to here.
This commit avoids `EBDT' and friends being looked up again and
again while loading a single embedded bitmap.
* include/freetype/internal/tttypes.h (TT_FaceRec)
[TT_CONFIG_OPTION_EMBEDDED_BITMAPS]: New fields `ebdt_start' and
`ebdt_size'.
* src/sfnt/ttsbit.c (tt_sbit_decoder_init): Move table lookup to ...
(tt_face_load_sbit): ... this function; also store the table size
and offset.
This removes unnecessary complexity of span merging and buffering.
Instead, the spans are rendered as they come, speeding up the
rendering by about 5% percents as a result.
* src/smooth/ftgrays.c [FT_MAX_GRAY_SPANS]: Macro removed.
(gray_TWorker): Remove span buffer and related fields.
(gray_sweep, gray_hline): Updated.
* include/freetype/ftimage.h: Remove documentation note about
`FT_MAX_GRAY_SPANS', which was never in `ftoption.h' and is now gone.
`FT_Get_Advance' returns 0 for bitmap fonts. It first gets the
advance value from the font table and then scales it by the
`font->size->metrics->x_scale' field. But `FT_Select_Size' doesn't
set that value for bitmap fonts and the advance gets scaled to zero.
Taken from
https://github.com/behdad/harfbuzz/issues/252
* src/sfnt/ttsbit.c (tt_face_load_strike_metrics)
<TT_SBIT_TABLE_TYPE_EBLC>: Set scale values.
Since 2016-05-16 we detect infinite recursion directly.
* src/sfnt/ttload.c (tt_face_load_maxp): Don't adjust
`maxComponentDepth'.
* src/truetype/ttgload.c (load_truetype_glyph): Don't abort if
`maxComponentDepth' is not valid. Instead, simply adjust its value
and emit a tracing message.
To match the logic in FDEF. The value of the end is only used for
bound-checking in `Ins_JMPR', so it may not have been obvious that
it was not recorded. Tested (as part of Font Validator 2.0) all the
fonts on Fedora and did not see any change.
* src/truetype/ttinterp.c (Ins_IDEF): Updated.
