The intent of this patch is to reveal attackers when they are in FOW/SOD, to avoid situations where attackers outrange their target.
I believe it works from the simulation POV, however the shaders make it buggy: because LOS is a texture, the units in SOD are rendered black-on-black, and in SOD are rendered 'grayed out' (but you can see it works).
I need to find a fix for that, obviously.
Looks like this: