09-13-2013, 10:30 PM
Chunk is generated only when it cannot be loaded from any of the supported storage schemas. So when you get an OnChunkGenerating hook, you already know that the chunk cannot be loaded. Now, no matter what that hook returns, the server will still generate the chunk; but you can manipulate the ChunkDesc parameter to force an almost-empty chunk generation - just fill the chunk with all air and set it as not using the default generators. Of course, this is not exactly cancelling the generation, but the MCServer architecture dictates that "any chunk must be available on request, either loaded, or generated". We do not support holes in the chunkmap - and neither does the client.