Do not generate SDF from bitmap if the
flag is not set. In some cases the bitmap buffer is freed but
still points to a valid address, to handle those cases check
the flag before accessing the memory.
src/sdf/ftsdfrend.c (ft_bsdf_render): Handle the above case. Also, return an error message if the bitmap's rows/pitch is invalid, otherwise the slot->buffer might be assigned to some invalid memory location.
src/sdf/ftsdfrend.c (ft_sdf_render): Same as above. Plus, move the outline back to original state after rasterization and not if any error occurs.
Signed-off-by: Anuj Verma email@example.com