The Photo-Realism Challenge: Physics

physics formula

Physics!  Uhn!  What is it good for?  Absolutely . . . er, quite a lot, actually.

Physics in games is one of those strange things that you don’t notice until it stops working right.  Example: in older games, where physics processing was not a big deal, no matter how an enemy was shot, he fell with the same pre-canned animation.  This is actually more realistic than modern games; people do not fly backwards when shot like in the movies.  But the point is, the animation was not dynamic, resulting in a death animation that did not look right.

dead mario

Yeah, I’m not buying it.

This brings us to a subject I don’t think I’ve covered in these articles before: what does “photo-realism” actually mean?  First, what it does NOT mean: photo-realism does not mean looking outside (or down a corridor or whathaveyou) and your game looking identical.  That would just be realism.  “Photo-realism” is looking like a photo (or video) of the world around us.  That means that post-processing effects, like light bloom, which occur in photography but not in real life, are a part of photo-realism.  Since video is involved, elements like motion blur are a big part of photo-realism.  Likewise, movie physics, although unrealistic, are a part of photo-realism.  When they get shot, people fly backwards.  It’s what we expect.


Sorry, real life just doesn’t look like this!

Enter physics!  A simple definition of physics is the description of matter moving through space.  This gets incredibly complicated, as you have to consider fluid dynamics, dynamic clothing, ragdoll physics, volumetric smoke, and so on.  As a result, PC physics engines have grown incredibly complex in their physics calculations, and I’ll try to (briefly!) give a history of video game physics (if I gloss over your favorite physics engine, sorry!).


Ooh, I can’t wait to see what happens!

The earliest 3D games, like Doom or Wolfenstein 3D, had no physics (I know, they were ray casted, but it doesn’t much matter here).  The enemies were sprites, and when shot, a pre-made animation caused them to fall when shot. There were no fluid dynamics, wind effects, volumetric smoke, or the like.  When the earliest proper 3D games came out, the first proper physics implementation was collision detection.  Collision detection determined two things: 1) were actors or players running into each other? And 2) did a bullet hit an actor or player?  The solution was to create a sort of box (called a “hit box”) around the models.  If the space of the bullet/ first actor interfered with the hit box of another actor, then action took place, and was resolved.

More robust models of physics were developed (ragdoll physics was especially popular—dead enemies actually fell like dead people fall!), but the biggest revolution occurred in 2000 when the Havok Physics middleware was released.  It was a risk—middleware that only did physics?—but it has paid off in dividends, looking at the impressive portfolio of titles that Havok has powered.


Kids these days don’t know it, but this was hot stuff back in the day!

The next big step forward in physics came from an unknown company named Ageia.  Havok worked (and still works) entirely via software through the CPU.  Ageia, however, had the idea of creating  physics co-processor (called the PhysX add-on card) to offload physics processing, improving both CPU performance and physics performance.  It worked wonderfully, but the industry adoption was lackluster—not enough people owned Ageia PhysX PPUs to attract developers, and there weren’t enough games to spur sales.  Fortunately, Nvidia, who were working on their GPGPU initiative, purchased Ageia.  Instead of using a special physics processing unit, physics is handled in CUDA cores.  The result is that the gamer gets the same unparalleled physics performance as they did with Ageia, with less hardware to buy.


Yes, accelerated physics really does make a huge difference.

This was not great news for AMD owners, however, and like AMD’s TruForm tessellation, PhysX adoption has been spotty.  Havok had announced a GPGPU physics solution, but since its acquisition by Intel, the status of Havok FX is unclear.  Still, it is clear that through increased parallelization of processor cores, physics simulations should continue to improve, and that is a game that everyone wins.

In closing, this article makes me want to get physical, physical.

Happy gaming!

  1. DQEight’s avatar

    Hey! I use a GTX 560 :-D


    1. Brian’s avatar

      Hey! I use a GT650 (M) the opposite :D


  2. The Budds’s avatar

    I still to this day say that Psi-Ops The Mindgate Conspiracy had one great physics engine. The stuff you could do with the game was just insane.

    On a further note… wish the game would appear on the PSN network u_u


    1. Niceneasy92’s avatar

      I’ve been praying for a sequel from the very first time I played that game. But I know it ain’t gonna happen. SIgh…


      1. slifermobile’s avatar

        I loved that game !!!! it was the best 3rd person game i have ever played :D and im downloading it right now !!!!


    2. DeathOfChaos’s avatar

      I’m glad I’m not the only one, lol.


    3. jrazorman’s avatar

      I was a great game I love it too.


      1. The Budds’s avatar

        Glad to find so many fans :)


  3. Da’s avatar

    You said that “earliest 3D games, like Doom or Wolfenstein 3D, had no physics”. Actually, the first video game I know to have physic simulation of some sort, is fps called System Shock, relased in 1994 (one year after Doom). So while everything you said is perfectly true if you asume that “earliest” means “before 1993″, I think that there were no revolution in terms of technology between the relases of those two games. I mean, System Shock was only a bit more advanced than Doom in terms of graphics, and it’s physics engine was realy simple.

    Also, what am I even talking about? In doom, if you shot into a wall with bazooka, you got knocked back off – same thing with enemies, barrels, ect. So doom got physics!



    enough of this!!!!! we want a hack for PSVITA for play isos


    1. DeathOfChaos’s avatar

      It’s outbursts like that that made coldbird leave the scene for a while. Keep demanding for something you don’t even haveto pay forand they may just keep it for themselves.


    2. Chris.Beanz’s avatar

      If you want the hack so much, why don’t you go and find a kernel exploit yourself? Since you seem to think it’s so terribly easy and all.


    3. TStrauss’s avatar

      1) Hacks are time consuming and difficult. You are welcome to continue checking a dead page because only hack news is posted, or bloggers like myself can continue to try and entertain you while you wait for the good stuff.
      2) NO ONE HERE SUPPORTS PIRACY. HBL/ VHBL cannot run piracy. The bigger hacks in the works are being developed in such a way that they block piracy. Despite idiotic arguments to the contrary, piracy hurts the gaming industry.
      3) You’re a greedy sod for wanting stuff for free. Really want an ISO? Buy it. It’s called capitalism.


    4. >_>’s avatar

      Then hack it yourself, puta.


  5. nevercall’s avatar

    sv_gravity 9999



  6. Tonakai’s avatar

    Great and informative article. The first line made me smile a little. An Edwin Starr reference is a great way to start an article. :P


  7. adriandevera’s avatar

    The article itself basically reflects how newer games today are focused reinventing the wheel by refining the game physics rather than interesting and creative gameplay itself… oh how lovely.

    New flashy games with lack of storyline, content and creativity. Sigh.


    1. TStrauss’s avatar

      The article is purely a tech retrospective. I always thought devs having more tools to make their art was a good thing. I guess not.


      1. The Budds’s avatar

        I think it’s something to the “Star Wars” effect. The last three films that came out first (still confusing I know) feel to have the best set design due to how hard they had to push their imaginations due to limitations.

        Take a look at the first three in the series (1,2,3) and it’s pumped up technology budget and it doesn’t feel the same.

        (one persons perspective on it:P)


  8. zakaiya’s avatar

    Great news guys i got my 3rd vita today!!! WOOO HOO!!!


    1. Mr. MaGoo’s avatar

      Nice, mine will be when 4g is released ;)


  9. dan’s avatar

    i dont care about vhbl i just want a meaningful update for the vita.


  10. pploco1996’s avatar

    What is the featured game in the last picture?



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