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Modem Range

Started by dexter9, 05 January 2013 - 08:19 AM
dexter9 #1
Posted 05 January 2013 - 09:19 AM
Hi
I have my own 24/7 tekkit server and i recently started using computercraft. I never new it was as good till now :)/> . I heard rumours that when the modems high into the air the range increases.Is it true and by how much? I was thinking about making a satellite as my base using redpower2 frames and launching it into space and using ccserver to forward rednet messages.Is it worth my time or does the altitude just increase the range so little that its not worth it?
Thanks in advance
Lyqyd #2
Posted 05 January 2013 - 09:24 AM
Default range at sea level is 64 meters, default range at skylimit is 384 meters.
dexter9 #3
Posted 05 January 2013 - 09:52 AM
Hi
In what way do you mean 384m? Is that how far down and across or is it just across?
dexter9 #4
Posted 05 January 2013 - 09:57 AM
And how do i download programs of the internet for computer os?
pielover88888 #5
Posted 07 January 2013 - 02:38 PM
You first must enable the HTTP api, (you can google how) and then if you see a pastebin link that's a computercraft program, use pastebin get (and then what you see after pastebin.com/, like: x094lxDE)
Lyqyd #6
Posted 07 January 2013 - 04:14 PM
Moved to Ask a Pro.
Heracles421 #7
Posted 07 January 2013 - 04:18 PM
Hi
In what way do you mean 384m? Is that how far down and across or is it just across?
Just across, the height doesn't matter
immibis #8
Posted 07 January 2013 - 04:49 PM
Hi
In what way do you mean 384m? Is that how far down and across or is it just across?
Just across, the height doesn't matter
Actually, it does matter. If they're at the same height, they can be up to 384m apart horizontally. If one is at the sky limit and the other is at bedrock, they can be up to approximately 290m apart horizontally, by Pythagoras' Theorem.
Heracles421 #9
Posted 08 January 2013 - 01:13 AM
Hi
In what way do you mean 384m? Is that how far down and across or is it just across?
Just across, the height doesn't matter
Actually, it does matter. If they're at the same height, they can be up to 384m apart horizontally. If one is at the sky limit and the other is at bedrock, they can be up to approximately 290m apart horizontally, by Pythagoras' Theorem.
Oh, so it's overall distance then, thanks for the correction
dexter9 #10
Posted 11 January 2013 - 06:19 AM
Thanks alot. It maybe is worth making a few satellites then.
ChunLing #11
Posted 11 January 2013 - 08:46 AM
It is totes worth it.
vcordie #12
Posted 13 February 2013 - 05:33 AM
Really sorry about the thread necro, but I didn't want to open a new thread:
Does anyone actually HAVE the formula for determining the range of rednet at different heights?
Does anyone know if the signal is "created" inside the block that the modem/turtle is in or is it created in the blocks surronding the turtle/modem? For example if I have a modem at skylimit at 0, 0, will a modem at 385, 0, or 0, 385, or -385, 0, or 0, -385 be able to recieve a rednet message from the first modem. If the signal is propucated from the same block, then no I wouldn't be able to, but if it's created in the blocks around it, then I should
Will a rednet signal cross an unloaded chunk? For example, if I have chunk 1, 2, and 3. Chunk 1 has a wireless chunk loading turtle at skylimit. Chunk 2 is unloaded. Chunk 3 has a wireless chunk loading turtle at skylimit. All chunks other then chunk 1 and 3 are unloaded. The rednet signal will have ot pass through unloaded chunk 2 to get to chunk 3. If I rednet.broadcast on turtle in chunk 1, will the turtle in chunk 3 recieve it or will chunk 2 have to be loaded.

Since turtles can only go up to 254 (one below sky limit) will they be broadcasting at the maximum range there or will they never be able to broadcast at 384m

Does the 384m include diagonally? Therefor if you were to look at a modem at skylimit from top down, on a 2d grid, thats 400x400, and marked every block that is within rednet range of that modem, would it be a giant square?

Does it propugate 384m from each side. That is, 384 in the -x direction, 384m in the +x direction, or does it go 384m as a total displacement for the signal.

I know im asking a lot of questions but I want to know everything about rednet, and how altitude interacts with it.
Lyqyd #13
Posted 13 February 2013 - 07:15 AM
1. minRange + (position.yCoord - 96.0) * ((maxRange - minRange) / ((world.getHeight() - 1) - 96.0))
2. The computer's coordinates are used. The range is from the center of the block. Any computer where the center of its block is within the range sphere is in range.
3. Yes.
4. Answer 1 will provide all necessary data on ranges at given heights. World Height is 256, I believe.
5., 6. The range is a sphere.
vcordie #14
Posted 14 February 2013 - 05:17 AM
Erm, I'm having issues visualizing the range as a sphere since everything is made out of voxels. Wouldn't it just end up as a giant cube?
Lyqyd #15
Posted 14 February 2013 - 06:39 AM
Nope, it's a sphere. If the point at the center of the block is inside the sphere, it's in range. I believe they iterate through the list of computers, calculate the distance between it and the sender, and queue the event if it is in range.
ChunLing #16
Posted 14 February 2013 - 01:02 PM
If you want to visualize a sphere of minecraft voxels, here's a link. These are the results of a sphere making turtle program.
daman4567 #17
Posted 12 September 2013 - 10:30 PM
the distance is not a space moved range, as in many turn based strategies, or a separate x, y, and z calculation, which would result in the cube mentioned above, but it is the pythagorean distance as calculated by x2 + y2 + z2 = d2 where d is distance in meters, and x, y, and z are difference in the respective coordinates in meters.