Also they definitely need to have a black hole or 2 chucked in and maybe some miniature binary stars orbiting at relativistic speeds
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.
Yes, I imagine it would affect gameplay quite a bit.
Can you think of a way to model a non-instantaneous propagation of this change that doesn't involve simulating oodles of photons wandering around the world?
Light from source A travels at the speed determined by the last speed-wavefront that passed it. This can be modeled by storing the speed on the sources, or by calculating from all gathered orbs in the world, and selecting the most-recent, when the time is calculated by (<time picked up> at <distance when picked up> at <speed of light before picked up>).
All such waves will be entirely contained within the previous wave because you cannot go faster than light and the speed only decreases, so all that matters is the speed before it was picked up, which is the speed the wave-front moves at (or does it move at the new speed? eh, pick either one, it doesn't matter.)
Then, for each orb picked up since the most-recent that affected the source, the time for the light to reach the observer is based on <distance to orb N> at speed <before orb N> until <distance to orb N-1>. Then repeat for orb N-1 until you run out of orbs. In this case, N would be the oldest orb whose wavefront has not yet passed the source.
It's a piece-wise calculation (the reverse of what's described), so it would be slower than instantaneous changes, but there's no need to model photons. And I would guess there's a reasonably-efficient way to calculate this on a GPU, so it could probably be real-time. Or it will be in a year or two.
On the plus side, I think I'm really going to enjoy this one. Thanks for the recommendation. :-)
It's a good story, (acceptably) good science (for a story book), and if I recall correctly from 20 years ago, very well written.
A sandbox approach might be good. I found myself wanting to experiment and change the speed of time myself.
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.
Also why is it that you can't see the Lorentz transformations until the final orb? I'd have thought that they'd be apparent somehow -- is it somehow cancelled out by visual effects?
There were also a few other documents I had but they don't appear to be hosted online anywhere.
The Lorentz transformations are not as apparent as the visual effects, they're not canceled out though. You can actually see them, try speeding up and slowing down when you have >50 orbs. You'll see a warped view and such :)
I also would have expected to see some sort of length contraction evident in things like the fence post spacing, but I never noticed any.
The end has all the crazy distortions that make it fun.
That aside... it's not the first game/toy about illustrating relativistic effects that I've seen before, for instance there's http://lightspeed.sourceforge.net/ and a funny little Flash game that I've tried: http://www.testtubegames.com/velocityraptor.html . Neither of them were very much fun.
This game was not very much fun either, but there was some promise, because at the end once I'd gathered all the orbs by moving slowly and methodically, I enjoyed skating around the level and trying to go as fast as possible without bumping into things. Hopefully someone will use the engine (they say they're releasing it next year) to do something really good.
Looks like the site it was hosted in is gone, though.
Also, be careful running with 100 orbs. I ran into a fence and got stuck on it.
Therefore the game is fine in so far as it has been presented.
You can also think about it being one of these "zero (weight of a photon at rest) multiplied by infinity (energy of objects moving at c) gives a finite number (actual energy of a photon)". The last number still behaves nicely.
Just read this on the site:
Some users have reported that the game may run on Windows XP and 2GB RAM. A known bug will crash the game on computers with some Intel graphics chipsets.
I have one of those hybrid graphics setups for laptops, so maybe that's the problem.
Just installed direct X from microsoft's site, still no joy.
Crashes just after intro.
Any other libraries I might be missing?
That's a hard damn problem. There are some extraordinarily well-funded research groups that are struggling to model any reasonably large number of interactions at that scale. State of the art supercomputing clusters can currently simulate systems of hundreds of thousands of atoms, not even in real-time, and they're still making some assumptions along the way, which might not hold true if you were to arbitrarily modify any fundamental constants.
You could probably write a physics engine that passably pretends to simulate some (non-arbitrary!) changes in fundamental constants. But it would be hard to guess what matter would even look like for different values of, say, Z0.
So the first thing I thought was, well low-scale speed of light giving wonky graphics is both cool and help getting the feel of relativity, but what about some Homeworld or a Master of Orion type of game with relativity ingrained inside the game rules and mechanics? Probably the music sounding Homeworld-esque helped.
Consider a turn-based game: a turn being irrevocably discrete and the same for all players, each entity, depending on its relative speed - hence time dilation/compression ratio - would get a different number of action points to spend each turn. You can globally compute each item action points because you're simulating the game universe.
You can extend this to virtually continuous time by compressing/dilating time depending on the player's relative reference frame, and then you could cap the flow of time so that min_flow=real_time or max_flow=real_time, or even mean_flow=real_time. I could see this becoming a problem for say, a FPS game where the player would feel relativity as time slows down or goes faster, but for a much more global game applying such a scheme would make him witness each unit/planet/whatever relative reference frame time dilations/contractions from a sort of god-like reference frame. In a single player scenario (where you don't need base time flow synchronicity between players) this god-player could even change his own reference frame by scaling his base time flow between say min_flow and max_flow.
Try modelling the twin paradox that way, for instance...
It's totally worth getting to the end (took me about 10 minutes) so you can play around for a moment without the colour shift affects. Would be really cool to have a version where you could do that.
Well done to the creators.
It's quite awesome anyways. Funnily if you change direction, that alone triggers no relativistic effects.
I think the limitation would be on the GPU side, or at least it was on the system I was testing on.
The person mentioned they would be doing some gaming on it, so I pointed out that the new Air would almost certainly have Intel HD 3000 graphics and that the Nvidia chipset in the older MacBook Air was better overall for that sort of thing.
Someone proceeded to try and rip me a new one, chastising me for having the gall to recommend purchasing a previous generation laptop. I said I owned an Intel HD 3000 MacBook Pro and even on that vs the Nvidia 320M MacBook Air, the Air performed better when it came to gaming.
He called me a liar, said it wasn't possible and that the HD 3000 chipset couldn't be the culprit. Here we are a year later, and I've been proven right countless times. I'm sure this is interesting to nobody, but it's nice to get a little vindication when someone was laying into you that hard.
e: Ah, but it actually runs fine on my 2010 unupgraded 11" Air. I'd guess a higher resolution screen would hurt performance, though.
That captures what distinguishes a game (as an artform) from other media. You could throw in some qualifiers to perhaps narrow it down (is paying your taxes a a game?) but it's not really necessary.
Although your particular example is kind of amusing, given the prominent role of the Prisoner's Dilemma in discussing elementary game theory! :P
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.
> IN PROGRESS OpenRelativity is a set of tools for simulating the effects of traveling near the speed of light in the Unity3D game engine.
> The team is currently refining the documentation, usability and features in OpenRelativity, targeted for release as a free, open-source package in 2013, to allow others to produce more simulations and games about traveling near the speed of light.
So, it will only be availible in 2013
However, this may be the Portal 2 Episode 1 game mechanic.
Also, relativistic motion doesn't appear to affect the movements of the other actors, though it's kind of hard to tell for certain.
As you move in relativistic speeds, your eye hits more photos, even those going sideways (or backwards), because the photons at an angle are slower than your eye (imagine a car moving fast through the rain, even drops that go in the other direction will hit your windshield).
Therefore, your field of vision grows (you can see things behind you), but only when walking forward.
I haven't read anything about going backwards, but I imagine that your field of vision would shrink, as you are now faster than photons that would previously hit your eye. My guess is that you would only see photons coming directly to you from your front, until you reached the speed of light and went blind (or could see 360 degrees, moving forward).
The observable change is the separation between photons (wavelength) caused by a moving source.
(correct me if I'm wrong, I'm terrible at physics!)
It actually helps to just forget about relativity for a moment, and think about the angles light from distant objects will have to take to intercept you. Then it becomes more clear.
I'm not sure I'm missing a step going from "wider fov" to "things seem farther away", maybe I am...
It would be nice to see a write up of exactly what effects they considered, though.
One is that the actual size of things changes. That's length contraction.
But the other is that, because you are moving at such high speeds, how you observe objects is also affected. That's what StavrosK discusses in the adjacent post.