Is there a way to know if lava is next?

[Nutty8]

Hello! My first topic here ;)
Sometimes, when playing Minetest, I tried to find lava lakes to make a Nether portal (I have a Nether mod installed). But then, the wiki says that lava are generated below Y = -273 (except for mg v6, but I never use v6). https://wiki.minetest.net/Lava
I digged down until I hit something like Y = -400 and found a HUGE cave, a giant open space in the underground, it was full of ores and way too dark. I walked through the cave placing torches everywhere (almost 600, and didn't covered even a half of the cave), but no sign of lava. It's almost funny how I never saw lava in Minetest unless by screenshots on the web (laughs).
So, is there a way of knowing if there's lava next to me?

[paramat]

What you found was a 'cavern' which is different to the smaller 'large caves' that sometimes contain lava.
Lava is intentionally not in caverns to avoid massive lava floods that also affect game performance.
You can write a mod that searches for lava around you, otherwise just keep exploring, it's easy to miss the lava caves but they certainly do start at y = -273.

[Vapalus]

Is there a mathematical formula which determines where lava is?

[Nutty8]

What you found was a 'cavern' which is different to the smaller 'large caves' that sometimes contain lava.

Understood, I cant lie about being scared of that giant infinite darkness in underground, I looked at the minimap and saw a big green mark and thought "What the hell is going on??".

Lava is intentionally not in caverns to avoid massive lava floods that also affect game performance.

Yeah, I also tried to look at the bottom of the cavern, but there wasn't a single sign of natural light or lava. I was disappointed but I got the reason why it isn't there.

You can write a mod that searches for lava around you,

I would really like to write mods. I know how to program and stuff (mostly in C++) but really get confused when dealing with Lua. And would like to wait until Minetest 0.5 is released.

otherwise just keep exploring, it's easy to miss the lava caves but they certainly do start at y = -273.

I will certainly do that, thanks for the help ;)
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Here's the cavern

[twoelk]

nice
you could share mapgen version, seed and coordinates for others to explore your "situation" :-P

there are a few little cheats to find lava - but that would only be half the fun wouldn't it

[BBmine]

In your mineshaft, you can stand between 2 spots to place blocks, and then place a block in one of the spots at eye level. Now you should be able to see through the stones and ores ;) Or you can make a texture pack that uses default:glass (or something similar) for default:stone.

[paramat]

> Is there a mathematical formula which determines where lava is?

Lava instead of water is determined by a 3D noise, which would help a little, but whether a cave is flooded is determined by a pseudorandom chance which is much more difficult to calculate.