Not enjoying my time with sunlight propagation in block game but at least it got me to optimize the MarkReachable* function in the lighting propagator which was taking up a third of the runtime for lighting propagation so that's something I guess

*because I propagate lighting to diagonals and corners of all 3x3 neighbors of a block to get more spherical lighting the propagator has to know if those neighbors are actually reachable from the current block which is what MarkReachable does