Avoid unnecessary calls to gimp_temp_buf_data_clear() in various
places, where either the entire buffer is being written to, or most
of it is, only requiring clearing the edges.
(cherry picked from commit 9d19e804ed)
Promote the precision of generated brushes to 32-bit float, and
modify brush preview generation, and gimpbrushcore-loops, to handle
float brushes. This avoids posterization in large brushes.
Note that non-generated brushes are still uint8.
(cherry picked from commit 8ef1113dee)
The parallel_distribute() family of functions has been migrated to
GEGL. Remove the gimp_parallel_distribute() functions from
gimp-parallel, and replace all uses of these functions with the
corresponding gegl_parallel_distrubte() functions.
(cherry picked from commit 2736cee577)
Move gimp_brush_core_{subsample,pressurize,solidify}_mask() to a
separate gimpbrushcore-loops.cc file, so that they can be C++-ified
independently from the rest of the code. The next commit
parallelizes them.
