As per
viewtopic.php?f=25&t=50154
I am trying to make an ambient effect (i.e. not tied to any entity) that transforms tiles into other tiles, but the only way I know of to get the valid "in world" positions are using the surface:getchunks, which returns the ChunkIterator. The problem with that is that it provides no information on the number of chunks that it will return, nor does it provide random access into the chunks. As my script has to run in on_tick, even running every 5s creates a large lag spike on worlds with many chunks.