Conditions for Grass Spreading

[Kimbblesrath 503]

I have some questions about how grass spreads. 

 

• Does it require a certain rain, evt, temperature, etc. value?
• Will it grass from one type of dirt spread to another type of dirt?

As much info as I could get about grass would be good. thanks.

[tenterro 60]

Yeah, I noticed too that grass spreads too slow. I formed ground many days (irl) ago and grass still covered all dirt blocks. How can you make it spread faster?

[Kittychanley 1,002]

The grass spread mechanic is essentially the exact same as in vanilla. If a grass block has a light level of at least 9, is not underwater, and it is touching a soil (dirt, clay, peat) block, there is a chance that it will spread onto that soil block. It doesn't matter if the grass block is made out of a different type of dirt, peat or clay, as long as it is a grass block. The same goes for dry grass.

 

If you want the grass to grow faster, use the same mechanic as in vanilla and light the whole area up with torches. That way at night, those are the only grass blocks that are even trying to spread.

[Kimbblesrath 503]

So rain, EVT, and things like that have no effect on it?

[Kittychanley 1,002]

Rain and EVT simply determine if it will be regular grass, or dry grass. They have nothing to do with the actual spreading of the grass.

[Kimbblesrath 503]

Well, this is odd. My grass has started spreading much faster than it used to (only one block had spread over a long period of time before) now that I've replaced the top layer with granite dirt (the same type of dirt as the grass I was trying to get to spread).

[micmastodon 41]

The grass spread mechanic is essentially the exact same as in vanilla. If a grass block has a light level of at least 9, is not underwater, and it is touching a soil (dirt, clay, peat) block, there is a chance that it will spread onto that soil block. It doesn't matter if the grass block is made out of a different type of dirt, peat or clay, as long as it is a grass block. The same goes for dry grass.

 

If you want the grass to grow faster, use the same mechanic as in vanilla and light the whole area up with torches. That way at night, those are the only grass blocks that are even trying to spread.

 

I have a lot of grass that wasn't spreading AT ALL (it has been years in-game) so I did an experiment. It turns out that at least in 0.79.17, grass won't spread from clay or peat grass blocks. I don't know if that's a bug, or just part of the game.  Dirt-based grass spreads just like vanilla. Here is a link to my video experiment.

[GopherAtl 22]

micmastodon, not sure if it would be a bug or not, that's up to bioxx & dunk, but that's not surprising to me. It's not dirt that random ticks to grow grass if grass is nearby, it's grass that random ticks to have a random chance to spread. So, kimbblesrath, it sounds like in your case the small amount of grass took a long time to start to grow - it had to wait for the few grass blocks to get random ticks, and for one of those ticks to successfully spread. In the most extreme case, starting from one grass block, once it spreads to a 2nd, it will take, on average, half the time to spread to a third, a third the original time to spread to a fourth, etc. It'll slow back down somewhat when it starts running out of places to spread to, as I'm pretty sure, like mushrooms, on a random tick it picks an offset first, then spreads only if that tile can accept grass, so by the time you're down to a single dirt block left to cover, even though there's a lot of grass random ticking, one has to randomly pick that one specific block to try to spread to.

[Kittychanley 1,002]

I have a lot of grass that wasn't spreading AT ALL (it has been years in-game) so I did an experiment. It turns out that at least in 0.79.17, grass won't spread from clay or peat grass blocks. I don't know if that's a bug, or just part of the game.  Dirt-based grass spreads just like vanilla. Here is a link to my video experiment.

 

Assuming you mean 78.17, but looking at the code its probably a bug. PeatGrass and ClayGrass both correctly extend the DirtGrass class, but it appears they accidentally overwrote the method that DirtGrass uses to spread. So what you saw makes sense because the peat and clay grass blocks aren't ticking or even trying to spread.