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Transform Any Unity Project Into a Relativistic Playground With OpenRelativity

Posted by Soulskill on from the aim,-calculate-lorentz-transform,-fire dept.

schirra writes "The MIT Game Lab has just released the graphics/physics engine from its popular game A Slower Speed of Light as an open-source project, allowing anyone to play around with the effects of special relativity using Unity3D. While the hope is that game developers and educators will use OpenRelativity to develop new kinds of relativistic games and simulations, that shouldn't stop those with a casual interest from playing around with these wicked cool effects. For the physics inclined, these effects include Lorentz contraction, time dilation, Doppler shift, and the searchlight effect--though a PhD in theoretical physics isn't required to enjoy or use the project."

28 of 40 comments (clear)

  1. What about by viperidaenz · · Score: 2, Funny

    spaghettification? What good isa physics engine if it can't turn every day objects into noodles?

    1. Re:What about by ArcadeMan · · Score: 1, Funny

      Screw your spaghetti. I want a physics engine that turns every day objects pink and invisible.

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    2. Re:What about by buchner.johannes · · Score: 2

      spaghettification? What good isa physics engine if it can't turn every day objects into noodles?

      Spaghettification is classical tidal forces, you don't need a special relativity engine for that, just a compact heavy object. What I would like to know is whether the engine also considers general relativity? Probably too complicated though, deforming space and so forth.

      --
      NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
    3. Re:What about by Anonymous Coward · · Score: 2, Informative

      From what I can tell (I just played their example game), its not a physics engine, just some tweaked shaders (and likely tweaked culling to match). The only stuff of real interest here are the rendering changes. There may be some physics in there, but the dynamics type physics wasn't very interesting/apparent.

      It looks like the distortions are done in the vertex shader, which means you need high vertex densities for high distortions to look reasonable (geometry shader based tessellation would resolve this). It was hard to notice the issue in the game-play due to the fast motion (it was hard to really see the effects very well), but it really stands out in at least on of their screen shots. In many games this will cause gaps in the models, and where models meet, so expect the distortions to not be a trivial dropping effect when you have overlapping meshes or T joints. I've tried simpler distortion effects in some of my games, and it had bad issues with large triangles not deforming accurately and thus leaving huge gaps between the ground and meshes placed on it. Their map was made with this in mind, and you would need to take it into account if you apply this to your game.

      It looks like they did the minimal thing, plus some UV an IR textures, which is a nice touch. Nothing amazing here, but pretty cool anyway.

    4. Re:What about by fuzzyfuzzyfungus · · Score: 2

      From playing with the demo last time it was mentioned, their implementation simulates the optical effects of varying the speed of light(getting massive doppler shifts at walking pace made me want to puke); but doesn't simulate(beyond a very rudimentary 'running and jumping on a plane with some scattered scenery) changes in mass, deformation of either objects or space or both. The new release may be more comprehensive, haven't had a chance to look at it yet.

    5. Re:What about by Anonymous Coward · · Score: 1

      After playing a bit more, some more bugs:

      Mushrooms, and a couple other things glow really bright in the far UV. Much brighter than any place in the sky, so it can't be scattered light, they are just powerful UV lightbulbs.

      If you just hold "s" to move backwards, even if up against a wall and thus not moving, the relativistic effects are out in full force, as if you were moving.

      Also, the complete lack of any directional lighting is kinda strange. No sun, no shadows. Everything is just kinda lit, and some thing apparently glow in some parts of the spectrum super bright, where other things are solid black. Strange.

      I tried to observe the time dilation effects on the moving dudes, but since they have no animations, I couldn't really see any effect there. I'd much rather have the trivial demo world from their video than a game like this. Or at least a place without so many fences so I could move straight while looking around for a while.

    6. Re:What about by Anonymous Coward · · Score: 1

      The developers had to make a few considerations w/r/t user experience that are not physically accurate. You can move when colliding with objects because testers found jarring halts when colliding with objects disorienting, especially given how intense the relativistic effects can be at particular speeds of light. Also, you can have the trivial demo world—it comes packaged with OpenRelativity!

    7. Re:What about by viperidaenz · · Score: 2

      I just wanted an excuse to mention spaghettification.

    8. Re:What about by CapOblivious2010 · · Score: 1

      What I would like to know is whether the engine also considers general relativity?

      Apparently it considers quantum effects, too - at high speeds I was able to tunnel through the fence, but then I didn't have enough room get to back up to speed to tunnel out!

  2. a newer version.. by gl4ss · · Score: 1

    ..for those wondering if this was a cyclic time thing from slashdot.

    --
    world was created 5 seconds before this post as it is.
    1. Re:a newer version.. by buchner.johannes · · Score: 2

      world was created 5 seconds before this post as it is.

      This hypothesis is constantly disproven. Search for Boltzmann brains for research, or this neat talk:

      --
      NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
    2. Re:a newer version.. by wonkey_monkey · · Score: 1

      This hypothesis is constantly disproven.

      Surely the whole point of that hypothesis is that it can't be disproven? You can declare it as unlikely as you want, but can you really prove it can't have happened?

      --
      systemd is Roko's Basilisk.
    3. Re:a newer version.. by gl4ss · · Score: 1

      world was created 5 seconds before this post as it is.

      This hypothesis is constantly disproven. Search for Boltzmann brains for research, or this neat talk:

      it doesn't disprove the possibility nor does it have anything to do with the idea that everything was kickstarted five seconds ago with everything in place. though I admit that I don't like the idea that world was created so that it already had my signature written ready for me and that I would have already an intention to press submit at creation, it's kind of a kick in the nuts since if it was so then I was kickstarted with the idea that I have some kind of free will as well - fucking pranksters whoever did this I tell you!

      --
      world was created 5 seconds before this post as it is.
  3. KSP by goertzenator · · Score: 3, Insightful

    Would go great with Kerbal Space Program.

    1. Re:KSP by HeckRuler · · Score: 1

      velocities requiring relativistic corrections

      "Requiring" is such a strong word. GPS satellites in orbit REQUIRE adjusting for time dilation due to their speed. You know, cause we care about nano seconds when placing our quadcopters between three satellites. That's current modern technology, not science fiction. Welcome to the future.

      Do we care that the Kerbal (who are currently immortal, do not breath, and can withstand infinite G forces) that is coming back from his decade long mission that overshot the moon has experienced an extra second or two? Eh, probably not. If they ever implement time-delayed communications, it could be an issue.

    2. Re:KSP by Nyrath+the+nearly+wi · · Score: 1

      I'm working on an unreasonable modded part right now, as a matter of fact. Ever hear about Project Orion?

      http://forum.kerbalspaceprogram.com/showthread.php/28428-Orion-aka-Ol-Boom-boom

    3. Re:KSP by braindrainbahrain · · Score: 1

      I second the motion. Can't wait to see Kerbal Interstellar Program.
      Devs: Holler if you need help.
      OTOH, OpenRelativity is open source. Can an API to KSP be worked out to work with OpenRelativity? We'll take care of the rest.

  4. Link to the game by the_other_chewey · · Score: 4, Informative

    OK, so there is a game called A Slower Speed of Light...
    How about linking to it?

  5. Re:Lorentz contraction? by camperdave · · Score: 2

    It depends on the frame of the observer. We can detect certain particles from space that, if they weren't "seeing" a shorter atmosphere, wouldn't make it to the surface. They'd decay first.

    --
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  6. Dang, if I didn't have projects already... by Dr.+Manhattan · · Score: 1

    I'd see about making a game based on Redshift Rendezvous by John E. Stith.

    --
    PHEM - party like it's 1997-2003!
    1. Re:Dang, if I didn't have projects already... by ConceptJunkie · · Score: 1

      I bought that book based on a recommendation the last time I saw a story about this project. It was definitely a fun book, and Stith did a good job extrapolating the effects of his new physics.

      --
      You are in a maze of twisty little passages, all alike.
  7. Re:Unity??? by UnknownSoldier · · Score: 1

    Unity _engine_, not the Unity _UI_.

    As in a _game_ engine that runs on Windows, mobile, etc.

  8. Re:Lorentz contraction? by mpeskett · · Score: 1

    Every so often, an idea that I thought maybe I at least semi-understood just goes and throws a fresh curveball.

    That is bug-fuck insane and I love it (well, more properly, our intuitions are bug-fuck insane when applied to things moving at relativstic speeds, but I guess insanity is also relative)

  9. It's a relativistic dupe! by Megane · · Score: 1

    http://games.slashdot.org/story/12/11/07/1559210/mit-slows-down-speed-of-light-in-new-game

    Well, sort of. I'm going to guess that the difference is now they've released their code.

    --
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  10. Re:That's nothing! Let me see them run it on Linux by kwbauer · · Score: 1

    With all the copulating in your post, I imagine the things you wished for will happen all by themselves.

  11. Re:Unity??? by Arashi256 · · Score: 1

    Fail.

  12. Re:Lorentz contraction? by camperdave · · Score: 1

    Maybe you mean things moving at sufficient speeds relative to the observer to render Relativistic effects noticeable.

    Yes, that is the definition of relativistic. The V^2/C^2 factor in the equation has to be greater than 1%, I believe.

    --
    When our name is on the back of your car, we're behind you all the way!
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