Dividing the map into areas seems to be easiest solution and I will probably take that route. Though I still wonder how games like DwarfFortress or townseed, or others of thet style manage to do it. They can walk between zones like if it was a huge continous world.

A link to that engine you mention would be great, but I am not sure about SSE2. All of today's computers have multithreading, but if I understood SSE2 correctly it is 128bit processing? If so I guess I won't be able to use it, most processors are 64bit now (like mine). Unless by having a dual core 64 bit processor that engine does it's magic on it's own to push 128 bits to both simultaneously... Mabe I have understood SSE2 wrong and am just speaking nonsense. I guess that is probably the case as a 128bit engine seems not very practical as most of the developer's potenciall clients would probably have the standard 64bit processing (and some may even still be using 32bit processors), so I guess I have understood SSE2 wrong?