Is that picture the symbol for ACT?

I don't see any permissions for modpacks. I plan to use this a lot on my server, and others will probably need to have it to connect. Would it be OK to add?

Is there something similar for 1.9?

How do you define the size of a chunk?
Is it a square of 1*1 or do you define it with its usually size of 16*16?

If you define it the usual way then you have a calculation error somewhere.

Example:
At the moment you define a square with the size Xmin=0, Xmax=1000 and Ymin=0, Ymax=1000 to have a chunk count of 1000000. But that is not the chunk count. It is the block count of one height layer
To get the usual chunk count you have to divide this through 256 (16*16) which leads to a chunk count of 3906,25

If I'm true there then you should recheck your code to avoid miscalculations and possibly mismatched chunk generation caused by that error.

The LENGTH of a chunk is 16 blocks. Hence, if you say "pregenspawn 100", the mod will pregen in a radius from spawn with a length of 1600 blocks. (100chunks * 16 blocks/chunk).

Your world, in this example, will be 3200 blocks in diameter.

Does it generate mod ores and bioms?
A remember some time ago it didnt

An option to throttle the pregen functionality would be great for those with less than a monster of a machine. It can crash the server even on a fairly beefy dedicated machine.

I have pregenned this on my own machine many times, no problem. I am also currently pregenning on MinecraftServerHost, and CPU is at 23-30%. Unless you have a low end/old machine, I think you'lll be fine! By the way, I'm running with 225 mods. With heavy terrain generation.

This is exactly what I was looking for, works great and there is nothing else like it.

Thank you soo much.

When using the pregen commands, it generates an entity in every chunk, seemingly. Having thousands of entities makes it generate chunks much more slowly. Is there a way to fix this while it generates?

You might want to clarify the pregenspawn description. I thought nchunks was the number of chunks it would generate when it is actually the radius (in chunks) around spawn. I discovered this with the command "/pregenspawn 500" expecting 500 chunks to generate and now my server is generating 1,000,000 chunks.

So the /set spawn is doing nothing for me. It registers that it worked, and the game tells me I've set the spawn, but then when I die, right back to the normal spawn location.

I've tried exiting the world and going back in, still doesn't work.

Any ideas on what I might be doing wrong?

Also, does this allow for spawning underground, or in buildings? It has a Y value, so I assume it would right?

I think many would prefer the pregen command to structure the coördinates as minX minZ maxX maxZ