Mark de Wever b5240e1bf9 Rewrite the blending algorithm.
The rewrite only has minor visual differences, ImageMagick's

`composite -compose difference'

shows no visual differences.

The change makes it possible to optimise the code on the ARM Cortex A8
using NEON instructions.
2012-03-31 14:45:23 +00:00
..
2012-03-31 14:45:23 +00:00