I know that this question was asked a long time ago, but just thought I'd give an update and a correction for future people that read this. (please consider that things may also change in future)
Ok, so first of all, you mentioned that a Chunk is 16x16 block around the player. This is incorrect. A chunk is a section of the terrain and is nothing to do with where the player is. The chunk does not move. A chunk is a 16x16x256 (W,D,H).
So for the mob spawning. The quote you gave is correct, however, does not note that it is centred around the chunk that the player is standing on. So 7 chunks in every direction from the border of the chunk you are standing in.
And now for your question :)
Recently, (not sure when it started) height has become even more important for mob spawning and each chunk is split into segments. This is to reduce the amount the game has to render and does this by going up in 16 block segments starting from 1. So 17, 33, 49, etc. This is called the lc value and can be shown on the debug screen (F3). It is important for mob spawning, why? Because any segments in the chunk above the maximum segment that has anything other than air in do not get checked for spawning conditions. This therefore means that there are many less blocks to check which in theory will make your mob grinder or xp farm more efficient.
There is a fair amount more... however, I think this answers what you wanted. At least I hope it does ;) Best of luck guys.
Best Answer
I did some digging around in the folder that contains my Twitch Launcher's SkyFactory 4 instance, using an IDE to find references to "bounc" (sic) or similar. In
/logs/latest.log, I saw this:So, I removed the following lines from
/config/incontrol/spawn.json(should be at the top of the file):This was done with MC closed. I then saved the file, removed the mod's .jar, started up MC, and entered my existing world again. This time, hostile mobs now continued to spawn naturally despite the removal of the mod, and there were no such "unknown mob" errors relating to the
spawn.jsonfile in the game's latest log.Note that you may get prompted about some missing EntityEntry/SoundEvent IDs in the registry while entering your world, which normally happens when removing a mod. Simply hit "yes" and proceed with the loading.
Also, I did get impatient while waiting as I didn't know if what I did worked at the time, so I did toggle vanilla mob spawning off and on again, after which I saw hostile mobs naturally spawn in a large dark room that I'd built (no, toggling mob spawning didn't work without the edits to the JSON file, and no, the issue isn't the fact that hostile mobs don't naturally spawn too close to or too far from the player). Therefore, if the steps above don't work for you, do this as well:
/gamerule doMobSpawning false/gamerule doMobSpawning true(I posted this QnA pair after finding the solution in hopes that it saves fellow players out there the annoyance of the bouncy creepers. The novelty sure does wear off fast.)