• 0

posted a message on Minecraft astrophysical issues
Quote from smurfsahoy »
Okay, no I'm still right. Even with the limit on world size, the sun would have to travel impossibly fast OR the world would have to spin with impossibly huge centrifugal tensions. Here is the math:

1) The distance you can see is about 250m in either direction. So if the world can be 8times the size of Earth, and it has to be 500m wide at all points, the maximum length of a world in MC is 8 million kilometers long.

2) The sun can be seen with and moves at the precision of one pixel on my monitor, and the sky is about 3 monitor heights across = 3000+ pixels for me. This means I am able to detect a change in the sun's apparent angle of 0.06 degrees at noon.

3) We can thus construct a triangle and determine at least how far away the sun must be from me in order for its apparent angle to not change. If this distance is too far for the sun to travel up and down in one day at the speed of light, then we have a problem (under the geocentric hypothesis. There are other problems for heliocentric - see below):

X = 8 million km / (sin(0.06)) = 7.6 billion km

Even if the sun rose straight up and down (it doesn't. it moves in an arc which would take way longer than going straight up and down, but I'm being VERY generous), it would take 14 hours to travel this distance and back. In actuality in game, it only takes 10 minutes.

Which means the sun is moving at well over 100 times the speed of light to make it's journey, if we are geocentric.

_____________________

If we are heliocentric, and we are assuming the earth is spinning and the sun is staying still? Well then, imagine the world is rotating around its center axis, then the furthest point on the map is 4 million km away, and has to sweep out an arc length of pi*(4 million*2) km every 20 minutes, or over a million km per minute.

This is about 5% the speed of light. Okay, so far so good. But what is the centrifugal force of that mass moving at that speed?

Just take the last 50 meters of the earth. About 60 meters deep of feldspar x 500 meters wide by 50 meters long = 1.5 million cubic meters * 2,550 kg/m^3 = 3.8 billion kg

Which is 274,550,000,000,000 N of force, enough to yank the entire cross section of the world's solid rock apart from raw tension. And that's just the last 50 meter's contribution to the tensions!!! There are 4 million km in each direction spinning around!

(In this world, of course, I would travel east-west to make my point, not north-south. A long east-west world would have to spin end over end, causing these problems.)

Assuming MC gold weighs the same in MC as IRL, Minecraftians can lift 400,000 metric tonnes of gold. That's about the same weight as a 747 boeing jumbo jet at take off. They can also run at 14kmph while carrying this weight. I think it's safe to assume the materials their planet is made of is rather strong.
Posted in: Alpha - Survival Single Player
• 0

posted a message on Rough minecart booster length experiment
I did some testing too.

With no one in it = 14x the booster lengeth. With someone in it = 45x. Dunno about uphill.
Posted in: Alpha - Survival Single Player
• 0

posted a message on Tradeoff: Compact Circuits (REVERT CHANGES)
Practically speaking wires are mostly just "OH MY GOD LOGIC GATES ARE AWESOME *nerdgasm*" atm.

Circuit size speaking... I think the changes should be reverted, AND we should be able to choose which way wires 'face'. Only 2 directions to choose from, so it's not hard... Just make the wires 'face' the same way as the player when he places them. This way we'd be able to have wires running right next to each other without them linking up, which would literally HALVE the size of circuits.
Posted in: Alpha - Survival Single Player
• 0

posted a message on Guide: How to build combination locks
Quote from ZarroTsu »
Now explain button bit input locks too for us, since THEY WON'T BE BALLS EASY TO OPEN.

I would if I knew how. :biggrin.gif:

if you wanna stop someone 'cracking it', just make it like 12 bits. That's 4092. don't think anyone is gonna try 4092 combos. o.o

Quote from Blackwind »
So to simplify how this works, the different layouts mean 1 and 0, the levers either way have to match up.
What way is the lever meant to point to mean the different numbers?

Down is 1, up is 0.
Posted in: Alpha - Survival Single Player
• 0

posted a message on "red stuff" logic gates
Quote from Wervyn »
[R] [] [S]

[] [Q] []

Should still work for a NOR latch.

Also you guys are aware that any latch composed of NANDs can generally be converted into something that works almost identically using NORs just by changing replacing the gates one-to-one, right? All that usually changes is that the clock becomes low-edge instead of high-edge, and the positions of the S and R inputs switch.

"Well when life gives you lemons..."

Hrm, you're right. A JK FF made from NORs works fine, albeit J/K inputs have the opposite effect of a NAND JK FF... Tho this is easily gotten around by NOT gates.
Posted in: Alpha - Survival Single Player
• 0

posted a message on Tradeoff: Compact Circuits (REVERT CHANGES)
Hrm... Ironically, this actually make (N)AND gates smaller, altho you have to use 2 layers for the input wires.

Also the idea about the hoes and direction... I like the direction part. Having the wires facing direction be based on what direction your facing would be AWESOME, instead of this "auto" BS.
Posted in: Alpha - Survival Single Player
• 0

posted a message on "red stuff" logic gates
Well, NOR and NAND RS latches are only silghtly larger fortunately.

RS Latch NOR: = block with wire on it.

Or:
Bottom
[]

Top

[] [] []

NAND RS latch suffered the least.

[]
[]
[]
Posted in: Alpha - Survival Single Player
• 0

posted a message on Guide: How to build combination locks
Quote from Epicdemic »
Can't you just mine a hole in any part of this
:s

You clearly didn't read the disclaimer.
Posted in: Alpha - Survival Single Player
• 0

posted a message on Guide: How to build combination locks

Want your own combination lock to keep all your goods safe* behind locked doors? Here's how!

For the rest of this guide, means red stuff. can also be replaced with any block. Also note that should be attached to the dirt block next to them. are levers.

"So, just how do you build a combination lock?" I hear you ask. Well, it's real simple. Lets say you want the combination 1010.

1 is represented like this.

And a 0 this:

Simple eh? One more step! gotta link it all up, like this: (Note: = door on a block)

[] [] [] [] [] [] [] []

[] [] [] [] [] [] [] []

[] [] [] [] [] [] [] []

You can add any number of 1s and 0s. Go crazy and make yourself a 50 combination lock if you want!
Eg: 100010

[] [] [] [] [] [] [] []

[] [] [] [] [] [] [] []

[] [] [] [] [] [] [] []

[] [] [] [] [] [] [] []

[] [] [] [] [] [] [] []

Note that the door should be placed on the side (in an open position), so adding power to it will close it.

In case the door is too far away, add these to extend your cable:

That's all there is to it!

*By reading this document you agree we aren't liable for any goods stolen due to failure of combination locks, doors, or walls.
Posted in: Alpha - Survival Single Player
• 0

posted a message on [NotchBlog]Torches less annoying
Quote from Stakhanov »
Both options are acceptable , right now torches are prone to burning out unexpectedly when circuits and levers are packed in a small area. Note that since wires instantly carry information , this will not change a clock's timing.

You're doing it wrong.
Posted in: Discussion
• 0

posted a message on "red stuff" logic gates
Quote from Cheeseyx »
Anyone have an idea on how a button could be repeated in a button lock, or how to force one order of pressing? That would let you have a 72+ combination lock based on how versatile the repeat is, which would best any would-be thieves trying to guess the combo, and almost all thieves if you got adminium walls. The only weakness there would be the door. If there was a positive charge under the door, the thief wouldn't be able to remotely set off TNT to destroy the door. You could have destroying the door dump sand, filling a corridor with obsidian, but it wouldn't be 100% foolproof as long as steel doors can be destroyed.

If you had 4 buttons, and you wanted say up to 12... It'd be pretty damn complex. You'd need RS flip flops for memory, ways to designate your writing, etc etc.

Edit: Actualy thinking about it some more, it shouldn't be too hard if the combo is hard-coded. A reconfigurable one is the hard bit.
Posted in: Alpha - Survival Single Player
• 0

posted a message on "red stuff" logic gates
NAND RS latch. :biggrin.gif:

[] []
[]

[]
[] []

TNT = input/wire.
Brick = output/wire (this is required even if you don't use it).

Switching the input off will set the closer output on.
Posted in: Alpha - Survival Single Player
• 0

posted a message on "red stuff" logic gates
Quote from Samonite »
http://www.asic-world.com/digital/seq4.html

I just can't make it work though..
Remember that the right part is an RS NOR Latch.

That won't work even in normal circuits (I've tried in logic simulators). You need this... Just make J and K the same to get a T flip flop.

After 2-3 painstaking days I finally got a JK and T flip flop to work properly. Turns out the 4 gate versions don't work properly. Also turns out that the 2x2 RS Latch we're using is made from NORs, which has the lovely effect of breaking flip flops that use NANDs.
Posted in: Alpha - Survival Single Player
• 0

posted a message on "red stuff" logic gates
Quote from Metapyziks »
Reduced the size of my T-Flip-Flop from 16x12 to 12x8 ( half the size ):

Interesting, you came up with a way to pulse it... Neat.
Posted in: Alpha - Survival Single Player
• 0

posted a message on Integrated Circuit (IC) blocks
Yeh, if you gave it say, 3 layers, you could cross wires, which is all you need.
Posted in: Suggestions