FOV/LOS shape can now be altered by modules using a simple: core.fov.set_vision_shape("circle") . The parameter can be one of "circle", "circle_floor", "circle_ceil", "circle_plus1", "diamond", "octagon", "square"


git-svn-id: http://svn.net-core.org/repos/t-engine4@4404 51575b47-30f0-44d4-a5cc-537603b46e54