Topic: Interesting things when attempting to build underwater fortresses (Read 1454 times)

Andy Korth · « **on:** February 07, 2009, 01:33:22 am »

Hi all.

I was attempting to build an underwater fortress. But rather than the drain the ocean method, I decided to pump vast volumes of lava into the ocean, in the hope of carving out a large obsidian tower to the ocean floor.

I tried dropping the lava from the level immediately above the water and also two levels above the ocean. The result was the same:

A single tall spire of obsidian was created, and from there, the obsidian pancaked out into a circle, rarely extending beyond that one z-level. This meant I wouldn't be able to reach the ocean floor easily, this way.

Well, I took the next step of digging down into the disk I had created. I went down into that level, and channeled down, expecting the water pressure of the ocean all around me to swell up from the hole at my feet. Strangely, it did not. Well, from here, you could channel out the entire bottom of the construction, fill it with lava again, and repeat, all the way to the ocean floor. This would kind of suck, because you'd have to wait around for lava to dry up, or mix in more water, or something.. but I wanted to try it.

Well, this is where it gets weird. I accidentally channeled out the obsidian spire holding the whole thing up (I got to it via a bridge). Without the support, the whole thing fell down about 4 z levels and landed intact on the ocean floor:

http://kortham.net/temp/ISankThis4OceanLevels.png

This makes me wonder if I could somehow sink intact structures onto the ocean floor and make some good use out of them. One caveat is that the obsidian disk was not constructed- I understand constructions would have been destroyed.

For the interested, here was an earlier attempt- a bigger circle that connected with the land:

http://kortham.net/temp/oceanObsidian.png
http://kortham.net/temp/oneLevelLower.png

As you can see, there isn't much underneath that disk. It poured in just to the right of the three tile wide set of water tiles. That's where I feed the magma in.

Does anyone have more information about pouring magma into water in a multilevel situation?

sneakey pete · « **Reply #1 on:** February 07, 2009, 01:50:46 am »

Yes, i have a couple of techniques that i've always thought of for constructing underwater forts.

One of them is to drop "sheets" of magma down all at once. Do this by creating a holding chamber the same size as the area you want to create the obsidian on, with walls around a floor made of bridges. hook all bridges to a level, and pull all at once. Hopefully you have a falling sheet of lava (though i don't think this'll work).

The other method i was thinking of was simply casting the entire block (x*y*z tiles) above the ocean, removing the constructions, connecting it to a support and then dropping it into place.

Warlord255 · « **Reply #2 on:** February 07, 2009, 02:01:52 am »

Quote from: sneakey pete on February 07, 2009, 01:50:46 am

Yes, i have a couple of techniques that i've always thought of for constructing underwater forts.

One of them is to drop "sheets" of magma down all at once. Do this by creating a holding chamber the same size as the area you want to create the obsidian on, with walls around a floor made of bridges. hook all bridges to a level, and pull all at once. Hopefully you have a falling sheet of lava (though i don't think this'll work).

The other method i was thinking of was simply casting the entire block (x*y*z tiles) above the ocean, removing the constructions, connecting it to a support and then dropping it into place.

A less magma-intensive alternative would be to drop a "ring" of magma; this is much easier time-wise, and can be accomplished with the limited reserves of a magma pool, if necessary. It functions on the same principle as the sheet method, and upon completion, you drain out the water level by level.

Draining said water is difficult, however. Putting a central column in, hollowing it out, installing your pump chain and then opening up the bottom with a sacrificial dwarf might work.

An important consideration is that your target area of ocean floor is perfectly flat, or else your dropped sheets/block will be distorted.

Fossaman · « **Reply #3 on:** February 07, 2009, 02:04:41 am »

I think water pressure loses one z-level in height; I've noticed that it only flows up to the level below the highest level of the source, anyway.

The method I've considered using (haven't actually done it) is dropping one level's worth of magma at a time, so that it doesn't form a spire as you've described. Each layer would stack on the one below; it might be a little ragged, though. You'd want a larger diameter plug of obsidian than the fortress footprint.

Quote

The other method i was thinking of was simply casting the entire block (x*y*z tiles) above the ocean, removing the constructions, connecting it to a support and then dropping it into place.

I like. I suspect this would give you the most precision in the shape that your obsidian plug takes.

Martin · « **Reply #4 on:** February 07, 2009, 02:11:51 am »

Can you post the seed and location? I've never found magma next to ocean to play with something like this.

Andy Korth · « **Reply #5 on:** February 07, 2009, 02:27:18 am »

I actually didn't have much problems finding a location. I just ran around all the coastlines and found this map on the first one I looked at.

Here's the location:
http://kortham.net/temp/locationOfLavaAndDeepOcean.png

And the info and seed:

Spoiler (click to show/hide)

I kinda like the sheet idea, but boy.. it'd be a lot of work to set up the architecture for that. Even more so for making obsidian above the ocean and collapsing it. Other constructions would deconstruct themselves, correct?

sneakey pete · « **Reply #6 on:** February 07, 2009, 05:43:58 am »

Correct.

Now that i think of it, there's a series of maps on the DFMA where someone has done this (collapsing sheets of obsidian in at a time, i think). i'll try dig it up.

Edit: here it is
http://mkv25.net/dfma/map-3664-blockaderhyming

Andy Korth · « **Reply #7 on:** February 07, 2009, 11:48:42 am »

Quote from: sneakey pete on February 07, 2009, 05:43:58 am

Now that i think of it, there's a series of maps on the DFMA where someone has done this (collapsing sheets of obsidian in at a time, i think). i'll try dig it up.

Edit: here it is
http://mkv25.net/dfma/map-3664-blockaderhyming

That is fantastic! Thank you so much for finding this! Yeah, I can see he's got a pretty huge construction there for the sheet method, but it seems to be working pretty well. He's also alternating water and lava to speed things up, so that's cool.

I was very excited to see this:
http://mkv25.net/dfma/poi-7988-zerowaterpressureintheocean

It's the same thing that I had observed, where the ocean seems to have no pressure.

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Author Topic: Interesting things when attempting to build underwater fortresses (Read 1454 times)

Andy Korth

Interesting things when attempting to build underwater fortresses

sneakey pete

Re: Interesting things when attempting to build underwater fortresses

Warlord255

Re: Interesting things when attempting to build underwater fortresses

Fossaman

Re: Interesting things when attempting to build underwater fortresses

Martin

Re: Interesting things when attempting to build underwater fortresses

Andy Korth

Re: Interesting things when attempting to build underwater fortresses

sneakey pete

Re: Interesting things when attempting to build underwater fortresses

Andy Korth

Re: Interesting things when attempting to build underwater fortresses