Is it possible to have loaded 2 worlds at the same time? For example I want player to operate on one world, but have preview (could be in viewport) of second one. It can't be static image it have to be in real time. Maybe somebody have idea for some workarounds? I know I can make my own worldmanager class but that would be a LOT of work.

Well, if you use the correct area mapping(eg the two worlds do not overlap eachothers areas then yes, you could load two worlds with adding another world manager alongside the default world manager), and draw both of them(then again, you would either need to remap/recreate the player when he leaves on and enters the other, or you need to make him separately as a global object).

Without your own manager though, I am not sure it will contain all features you might want from having multiple worlds,eg how will it deal with physics objects(for alot of things having physical objects calculated while it being of no importance when you are on the other world far away from it, crossing from one world to the next(without doing something like waypoints along the world edges), the the question also comes in, should the world be using streaming mode or fully loaded mode).

Like zervox said it really depends on what you need in the second world and how different it is from the first one. You could use different drawing method to make changes in only the viewport for example if you dont want him to affect both, and then switch the drawing of the main screen and viewport when you want.

Ok, thanks you guys. It's looks like it can't be done without some solid work. With the deadline on the road, even the far one, I'm trying speed up things as much as can. Sadly I need two world working at the same time. (For my Tavern Simulator, one world is inside tavern, second is local map).

well, as I said in the first, you could do two worlds, the one world which the tavern inhabits(I am guessing it is really small compared to your world).

so lets say you have local map which is set to 50x50 areas, all you need to do is place the Tavern map(either in the same world or having a separate world) but place it at offset 100x100(this way you should be able to have them both updating and rendering and not collide) at the same time.

I just have to toss out ideas, because I am not sure of all the features you require of two connected worlds. : )