Hey there, Time for me to ask a question again (it's been a while since I've been sitting on this side of the thread). Basically my objective is to convert an entire world into another format. The conversion and all is working nicely, the only problem is that it currently only works with 2 settings: Convert all loaded chunks of the world Convert all chunks in a cuboid area, loading (generating) the ones that aren't loaded yet While this works in many cases, I want to be able to handle a world save of arbitrary size and completely get all the data out of it without creating all the unrequired chunks. (Think of minigame-maps for example. They are often full of empty space with relevant stuff here and there, possibly very far away.) Does anyone have an idea how this could be accomplished elegantly? Oh and the world I'm converting is temporary, so I load it manually in the plugin and unload it afterwards. If at all reasonably possible, I'd like to go without NMS code, but it probably won't be. Manually reading all the existing "r.x.z.mca" files requires NMS or you'll get insane. Just taking all their filenames and trying to load all 1024 chunks that they could possible contain also seems overkill. Any ideas? Thanks in advance! Okay, more digging through NMS code brought me back to RegionFileCache and RegionFile. I still can't wrap my head around how chunk saving and indexing is done with Java's RandomAccessFile, though. It looks like there could be a way to detect whether a chunk exists or not with some method in RegionFile. Anyone experience with it by any chance? EDIT by Moderator: merged posts, please use the edit button instead of double posting.