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Re:Minecraft@Home by siraben on Monday July 20, 2020 @07:13AM (#23896659)
I should also follow up with a technique that might be of interest to programmers. Some Minecraft blocks have textures that appear rotated in one of four ways. Turns out this rotation is pseudorandom, the rotation number is a result of seeding Java's rand.nextLong() with the (x,y,z) coordinate of that block.[0] This has been used for "malicious" purposes such as finding the location of a base from a single screenshot, which can lead to its destruction on anarchy servers. The author of the linked video used a CUDA search to find the location of a wall of netherrack.

[0] https://youtube.com/watch?v=6__hO4cc1pA

Re:Minecraft@Home by Balgair on Monday July 20, 2020 @03:54PM (#23901262)
Aside: 2b2t is the most notable of MC anarchy servers. Whenever I read about it, I'm amazed at the machinations of the people that play there. It's kinda like reading Eve Online after action reports of their big battles. I've no inclination to play on 2b2t, but it's great reading all the same.
Re:Minecraft@Home by Nannooskeeska on Monday July 20, 2020 @05:04PM (#23901895)
I have the same feeling about Dwarf Fortress. I absolutely love reading DF stories (see [0]), but the couple times I tried to play I just couldn't get into it.

[0] https://lparchive.org/Dwarf-Fortress-Boatmurdered/

Re:Minecraft@Home by kiaulen on Tuesday July 21, 2020 @03:23PM (#23910002)
I'm with you. Also hopeful that the DF steam release comes with a slightly easier to use UI.

If you want similarly hilarious stories, try rimworld.

Re:Minecraft@Home by sorahn on Tuesday July 21, 2020 @04:17AM (#23905197)
I'm curious about what the implications of some of these projects will be for 2b2t. Given that the seed is known, couldn't people start finding bases from screenshots using some of these clusters of 'rotations of textures 'tricks?
Re:Minecraft@Home by siraben on Tuesday July 21, 2020 @09:32AM (#23906654)
Yes, these techniques have been used to find bases and destroy them. Along with the texture rotation trick, there's also the position of bedrock whose distribution is fixed in every Minecraft world, so if you show exposed bedrock during a base tour you are at risk of leaking coordinates. Natural terrain is also another factor, so share enough images of the area surrounding the base and it can be leaked similarly.

See https://www.youtube.com/watch?v=I7Jz9RMybfM

Re:Minecraft@Home by hinkley on Wednesday July 22, 2020 @07:07PM (#23922538)
Shouldn't...

I know that Minecraft lazily generates the world, so the RNG for an arbitrary location has to be deterministic otherwise you get a mess.

Why isn't the RNG for tiles based on the world seed and the location? That's at least a billion times more search space, still deterministic.