[raster] Remove 5-level gray AA mode from monochrome rasterizer.

It was off by default and couldn't be turned on at runtime.  And the
smooth rasterizer superceded it over ten years ago.  No point in
keeping.  Comments suggested that it was there for compatibility
with FreeType 1.

550 lines down.

* src/raster/ftraster.c (FT_RASTER_OPTION_ANTI_ALIASING,
RASTER_GRAY_LINES): Remove macros and all associated code.

(black_TWorker): Remove `gray_min_x' and `gray_max_x'.
(black_TRaster): Remove `grays' and `gray_width'.

(Vertical_Sweep_Init, Vertical_Sweep_Span, Vertical_Sweep_Drop,
ft_black_render): Updated.

* src/raster/ftrend1.c (ft_raster1_render): Simplify code.
(ft_raster5_renderer_class): Removed.
4 files changed