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A Slower Speed of Light

gamelab.mit.edu

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Re: A Slower Speed of Light

#81

Post by xnxn »

StavrosK wrote: post #66
jasonwatkinspdx wrote: post #65

Earlier quoted context omitted.

Except that's not what we measure. Instead we find the speed of a photon depends only on the medium, not on the motion of the source or receiver.

You aren't listening to me. The speed of the photon is c in the direction it's traveling, a photon traveling due west is going north with no speed at all.

I don't think it makes sense to say that the speed of a photon is c "in a direction", since speed is a scalar quantity.

(correct me if I'm wrong, I'm terrible at physics!)

Re: A Slower Speed of Light

#82

Post by kzahel »

tzs wrote: post #61
flebron wrote: post #56

Earlier quoted context omitted.

I think if you don't go under the white arch, you can stay indefinitely in Lorentz transformations mode. At least, I stayed that way for several seconds if I avoided that arch.

ESC also seems to end it if you have 100 orbs, instead of taking you to the settings screen as I would have expected. Also, be careful running with 100 orbs. I ran into a fence and got stuck on it.

the same thing happened to me (getting suck in the fence), and pressing escape to try and turn the colors back on.

Re: A Slower Speed of Light

#83

Post by m_darkTemplar »

I(Ryan Cheu) was on the team that made this if anyone has questions!

Most of my work was on implementing the actual calculations for relativistic effects.

It was coded in Unity Game engine in C# mostly. The hard calculations are actually all calculated in a shader written in Cg (mostly just C) so they're on the graphics card.

Re: A Slower Speed of Light

#84

Post by m_darkTemplar »

adaml_623 wrote: post #2

I'm quite curious as to whether the speed of light across the game space decreases instantaneously when you pick up an orb or whether the change in the speed of light propagates at the speed of... umm light. Also they definitely need to have a black hole or 2 chucked in and maybe some miniature binary stars orbiting at relativistic speeds

It's instantaneous. There's no answer in physics for what should happen when you change the speed of light because that simply just can't happen. Therefore we didn't bother doing something like prorogation at the speed of light.

We don't do gravity calculations, along with a few other things because we didn't have time and they make the other effects hard to see.

In the future I would have liked to continue with the project and implement some of this though.

Re: A Slower Speed of Light

#85

Post by m_darkTemplar »

aristidb wrote: post #47

It's _barely_ playable on my 2011 MBA. Seems like the limitation is on the CPU side though. Either it's fairly unoptimized, or this relativistic stuff is just really demanding. It's quite awesome anyways. Funnily if you change direction, that alone triggers no relativistic effects.

It had to be written in C# in the Unity Engine so it's kinda slow. The other issue was that I had no access to the culling system besides just turning it off so every object in the scene is rendered every frame.

I think the limitation would be on the GPU side, or at least it was on the system I was testing on.

Re: A Slower Speed of Light

#86

Post by m_darkTemplar »

Deestan wrote: post #23
bobylito wrote: post #21

Is it even a game? It seems to me like a very interesting simulation but I don't see game design there...

> Is it even a game? Technically , yes: It has a goal (collect orbs) a challenge (navigate environment) and a difficulty curve (increased distortion). But it's really a tech demo, though.

The goal we were given at the start of the summer was just to create a tech demo, the team tried to make a game out of it as much as possible though. The original plan was to release a tech demo at the end of the summer and then make a game with it after, the after part hasn't started yet though, and I'm not sure if it will.

Re: A Slower Speed of Light

#88

Post by m_darkTemplar »

jychang wrote: post #30
slackson wrote: post #20

Earlier quoted context omitted.

I imagine it would be quite difficult to have working multiplayer relativistic mechanics. So far, I can only see single player mechanics working, which would restrict the appeal of such a game.

Yeah, multiplayer without a unified sense of "time" doesn't seem to work very well...

It was considered but there are some equations that still need to be worked out. We'd need to store the history of each player but I believe we decided it could be done.

Re: A Slower Speed of Light

#89

Post by gradschool »

The Lorentz transformation (as I understand it) pertains only to inertial reference frames moving at constant velocities relative to one another, hence the "special" rather than the "general" theory. However, the player seems to be able to stop, start, or change course at will. Wouldn't those actions cause lots of effects (e.g., gravitational waves, etc.) that are not accurately modeled in this simulation?

Re: A Slower Speed of Light

#90

Post by btilly »

gradschool wrote: post #89

The Lorentz transformation (as I understand it) pertains only to inertial reference frames moving at constant velocities relative to one another, hence the "special" rather than the "general" theory. However, the player seems to be able to stop, start, or change course at will. Wouldn't those actions cause lots of effects (e.g., gravitational waves, etc.) that are not accurately modeled in this simulation?

The special theory can handle acceleration perfectly well. What it can't handle is gravity.

Therefore the game is fine in so far as it has been presented.

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