[Ohrrpgce] SVN: teeemcee/11708 Implement Multiply blend mode.

[subversion at HamsterRepublic.com]

teeemcee
2020-04-08 05:44:23 -0700 (Wed, 08 Apr 2020)
361
Implement Multiply blend mode.

The reason I've picked these three is because they are the ones SDL2 supports
with all rendering backends (SDL_BLENDMODE_MUL was only added in the latest SDL
2.0.12, and I'm surprised to discover it requires premultiplied alpha unlike
the others). SDL also has SDL_BLENDMODE_MOD which is like MUL but total ignores
alpha/opacity.
---
U   wip/blit.c
U   wip/ohrhelp/sliceedit_blend_mode.txt
U   wip/sliceedit.bas
U   wip/surface.bi
U   wip/surface.cpp
U   wip/surface.h
U   wip/whatsnew.txt