Hahaa. Thanks for the inspirational links Deeph !
After reading about pathfinding algorithms & line of sight & field of vision I now have my first FOV code working. And its freaking awesome ! You can hide behind corners, shadows fall behind stones and stuff. I am projecting 8 rays (N,NE,E,SE,S,SW,W,NW) and interpolating a visibility map.
Walking along, shadow moving behind rocks and stuff ... you see inside buildings through windows and doors... it looks too awesome to leave alone. I'll make a video soon.
So I guess I'll continue for a while