Is it worth looking at the McRegion files?

I'm working on a plugin that has to do with saving and loading worlds. I'd like to be able to search through the world and be able to record all of the locations of a certain kind of block (for example a sign).

Code:

for(Chunk c : world.getLoadedChunks()){
            for(int x = 0; x < 16; x++){
                for(int y = 0; y < 128; y++){
                    for(int z = 0; z < 16; z++){
                        Block b = c.getBlock(x, y, z);
                        if(b.getTypeId() == 63 || b.getTypeId() == 68){
                            signSet.add(b);
                        }
                    }
                }
            }
        }

I know that if I use something like what is written above, it will take forever and perhaps even crash the server given the size of the map.

Would it be faster to search directly through the McRegion files stored in the region folder? If so, how would I go about doing this?

I read up on how the data is stored here: http://www.minecraftwiki.net/wiki/Beta_Level_Format

but I'm still not sure about how to go about analyzing the data.

Code:

try{
            InputStream in = new FileInputStream(src);

            System.out.println(src.getName());

            // Transfer bytes from in to out
            byte[] buf = new byte[1024];
            while (in.read(buf) > 0) {
                //What do I do here...?
            }
            in.close();
        }catch(Exception e){
            System.out.println("Could not read file "+src);
        }

Any help or direction would be much appreciated

 

You'd be best off using JNBT to read the actual chunk data if you wanted to go down this route.

 

fullwall's suggestion is a good one, but you will have to parse the MCRegion format before you can get at the NBT data for the chunks. The region files themselves are not in NBT format.

 

Ah, thanks for letting me know. Do you know of any examples of how to search for blocks of a certain type this way? or something similar?

 

@_Zenith_ once you've retrieved the block array, you just need to run through it with a simple loop and look for the block ID(s) you're interested in.

I'm not aware of someone doing this specifically, so unfortunately I can't be of help there. Parsing the MCRegion file will probably be the hard part though; accessing data from the NBT block should be pretty easy with the JNBT libary.

If you need an example of using the JNBT library, I have some code for my world generator that might be useful. It's not the regular chunk format, but it loads an NBT file and retrieves an array of block IDs (among other things).
https://github.com/Timberjaw/Dungeo...eonator/generator/DungeonRoomEditor.java#L241

 

Thanks, I'll check it out

 

sk89q has some mcregion parsing code located inside worldedit. You could check his source out on github...

 

I agree, sk89q has quite a bit of useful things on github.