Anurag Thakur authored May 18, 2021 and Werner Lemberg committed Jun 29, 2021

* .gitlab-ci.yml: Added jobs for building freetype on linux.

* src/raster/ftraster.c (black_TWorker): Move `arcs' from here...
(Conic_To, Cubic_To): ... to here to tighten their scope.
(Bezier_Up, Bezier_Down): ... Take the current `arc' argument.

Dominik Röttsches authored Jun 28, 2021 and Werner Lemberg committed Jun 28, 2021

Paint tables can appear before the `base_glyphs_v1` offset if the
font is produced with the layer list before the base glyph list.  In
this case paint tables can occur after the layer list but before the
base glyph list.  Checks in the 'COLR' v1 code were rejecting fonts
with this layout.  Improve these checks by calculating a minimum
offset after which paint tables can occur and use that in safety
checks.

* src/sfnt/ttcolr.c (Colr, tt_face_load_colr): Declare
`paint_start_v1` and calculate that as the minimum of the end of
layer list and base glyph list.
(get_child_table_pointer, read_paint, tt_face_get_paint_layers):
Use that in safety checks.

* src/raster/ftraster.c (black_TWorker): Replace the current line
offset with the pointer and drop the increment.
(Function_Sweep_Init): Take values as arguments instead of pointers.
(Vertical_Sweep_*, Horizontal_Sweep_Init, Draw_Sweep): Updated.

* src/raster/ftraster.c (black_TWorker): Move `band_top' from here...
(Render_Single_Pass): ... to here, and refactor.
(Render_Glyph): Updated.

We can bisect a band until it is just a single scan line.  This might
be slow and cause time-outs but if we need to impose limits it should
be elsewhere.

* src/raster/ftraster.c (Render_Single_Pass): Tweak sub-banding.

Some practical debugging work has shown that displaying level X of
an `FT_TRACEX` macro in the output of `FT2_DEBUG="...  -v"` would be
very helpful to find out which trace level should be selected.  As
an example, we now get output like

```
[ttobjs:2]    TTF driver
[ttobjs:2]      SFNT driver
[sfobjs:2]      not a font using the SFNT container format
[t1objs:2]    Type 1 driver
[stream:7]    FT_Stream_EnterFrame: 14 bytes
```

* include/freetype/internal/ftdebug.h (FT_LOGGING_TAGX): New macro.
(FT_LOG): Use it to add the trace level to the logging tag.

* include/freetype/internal/fttrace.h (FT_MAX_TRACE_LEVEL_LENGTH):
Adjust.

* docs/DEBUG: Updated.

FT_Render_Glyph picked up FAILURE or 1 returned from the raster
function, which became a confusing error code. Instead, return
Raster_Overflow in the unlikely event that banding does not help or
another meaningful error.

* src/smooth/ftgrays.c (gray_convert_glyph_inner, gray_convert_glyph):
Use Raster_Overflow when the rendering pool is exhausted and return it
if banding does not help.
(gray_raster_render): Use Smooth_Err_Ok.

* src/raster/ftraster.c (Render_Single_Pass): Return Raster_Overflow
if banding does not help or another error code.

* src/smooth/ftgays.c [STANDALONE_]: s/ErrRaster_/Smooth_Err_/.
(gray_convert_glyph_inner): Updated accordingly.

* src/raster/ftraster.c [STANDALONE_]: Do not abbreviate error macros.
(New_Profile, End_Profile, Insert_Y_Turn, Line_Up, Bezier_Up,
Decompose_Curve, Draw_Sweep, Render_Single_Pass, ft_black_render):
Updated accordingly.

Dominik Röttsches authored Jun 22, 2021 and Werner Lemberg committed Jun 22, 2021

* include/freetype/ftcolor.h (FT_PaintTransformed, FT_PaintFormat,
FT_COLR_Paint): Do it to make it harmonize with other names such as
'PaintTranslate'.

* src/sfnt/ttcolr.c (read_paint, tt_face_get_paint): Ditto.

Dominik Röttsches authored Jun 22, 2021 and Werner Lemberg committed Jun 22, 2021

* include/freetype/freetype.h: Cut section layer managament
containing 'COLR' v0 and v1 API and move it to `ftcolor.h` as
requested by Werner on freetype-devel.
* include/freetype/ftcolor.h: Paste that section.

Reported as

  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35312

* src/truetype/ttinterp.c (Ins_JMPR): Use `ADD_LONG`.

This speeds up handling of broken glyphs.

Reported as

  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35309

* src/autofit/aflatin.c (af_latin_hints_compute_segments): Implement
it.

See #1063
for more details on the bug.

* tests/README.md: documentation explaining how to
  build and run the tests with the Meson build.

* tests/scripts/download-test-fonts.sh: Simple script
  to download test font files to the 'tests/data/'
  folder.

* meson.build, meson_options.txt, tests/meson.build:
  Add 'tests' option to enable building and running the
  test programs, disabled by default.

* tests/issue-1063/main.c: Simple regression test to
  exhibit issue 1063.

* .gitignore: Ignore the content of the tests/data/
  folder for now.

We need to inverse inheritance of FT_GlyphSlot_Internal so that we
have a chance to free the rendered bitmap from the parent slot.

* src/type42/t42objs.c (T42_GlyphSlot_Init): Remove the internal parts
of the child `ttslot' and replace it with the parent structure.
(T42_GlyphSlot_Done): Updated accordingly.

* src/psaux/psintrp.c (cf2_interpT2CharString)
<cf2_escCALLOTHERSUBR>: Convert assertion into error, since the
problem can happen with invalid user input.

Test case is file

  fuzzing/corpora/legacy/oss-fuzz/5754332360212480-unknown-read

in the `freetype2-testing` repository.

* src/psaux/pshints.c (cf2_hintmap_adjustHints): Check for overflow
before emitting an assertion error.

* src/sdf/ftsdfrend.c (ft_sdf_render, ft_bsdf_render): Add padding to
`bitmap_top' and `bitmap_left'.

* sdf/sdf/ftsdf.c (sdf_generate_with_overlaps): Fix VC++ warning.

* devel/ftoption.h: Synchronize with
  `include/freetype/config/ftoption.h`.

Fixes #1062.

* src/sfnt/ttcmap.c (tt_cmap4_validate): Handle a too-small value of
`length` gracefully.

* src/sfnt/ttcolr.c (tt_face_get_paint_layers): In addition to the
existing sanity checks, ensure that the pointer to the layer to be
read is within the 'COLR' v1 table.

* src/sdf/ftsdf.c: Include `ftbitmap.h`.

* src/sdf/ftsdfcommon.h: Move function bodies to `ftsdfcommon.c`.
Include `ftobjs.h` to get definitions of `FT_LOCAL` and friends.

* src/sdf/ftsdfcommon.c: New file.

* src/sdf/rules.mk, src/sdf/sdf.c: Updated.

Since 8-bits is enough to represent SDF data we no longer require
16-bits for  this purpose. Also, we now normalize the output data
to use the entire 8-bit range efficiently. For example: if we use
3.5 format with a spread of 1 we basically only use the starting
5-bits. By normalizing we can use the entire 8-bit range.

* include/freetype/freetype.h (FT_Render_Mode): Updated description
for `FT_RENDER_MODE_SDF` regarding this change.

* include/freetype/ftimage.h (FT_Pixel_Mode): Removed
`FT_PIXEL_MODE_GRAY16` since no longer required.

* include/freetype/fttypes.h (FT_F6Dot10): Removed since no longer
required.

* src/sdf/ftsdfrend.c (ft_sdf_render, ft_bsdf_render): Allocate 8-bit
bitmap instead of 16-bit buffer.

* src/sdf/ftsdfcommon.h (map_fixed_to_sdf): Added function to convert
16.16 distance value to our desired format.

* src/sdf/ftsdf.c (sdf_generate_with_overlaps,
sdf_generate_bounding_box): Use the new `map_fixed_to_sdf` function
and also use 8-bit output buffer.

* src/sdf/ftbsdf.c (finalize_sdf): Output to a 8-bit buffer instead
of 16-bit buffer.

Ben Wagner authored Jun 01, 2021 and Werner Lemberg committed Jun 02, 2021

* src/sfnt/ttcolr.c (find_base_glyph_record,
find_base_glyph_v1_record): Adjust binary search.

Needs to be updated with change to unsigned.

Problem reported by Alexei.