Function `map_fixed_to_sdf` expects spread to be absolute
and not squared.
* src/sdf/ftbsdf.c (finalize_sdf): Pass absolute spread
while `map_fixed_to_sdf`.
* src/sdf/ftsdf.c (sdf_generate_bounding_box): Ditto.
* src/base/ftobjs.c (FT_Get_Paint): Operator has equivalent nested operands.
* src/bdf/bdflib.c (_bdf_add_property): Value stored to `fp` is never read.
* src/sdf/ftbsdf.c (bsdf_init_distance_map): Value stored to `pixel` is
never read.
* src/sdf/ftsdf.c (split_sdf_shape): Value stored to `error` is never read.
* src/sdf/ftbsdf.c (first_pass, second_pass): Fix range during forward pass.
Otherwise the index goes out of range for the last column.
Fixes issue #1077.
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.
Here is a breakdown of what the files will contain.
* src/sdf/ftsdfrend.c, src/sdf/ftsdfrend.h: The 'sdf' and 'bsdf'
renderers.
* src/sdf/ftsdf.c, src/sdf/ftsdf.h: The rasterizer for the 'sdf'
renderer.
* src/sdf/ftbsdf.c, src/sdf/ftbsdf.h: The rasterizer for the 'bsdf'
renderer.
* src/sdf/ftsdfcommon.h: Commmon properties and functions for both
rasterizers.
* src/sdf/ftsdferrs.h: Common error defines.
* src/sdf/sdf.c: For building a single object of the entire module.
Anuj Verma