Microsoft cooking up DirectX physics

Hardware acceleration for physics is still in its infancy, but Microsoft
appears to be wasting no time getting in on the action. According to an
on ExtremeTech
, Microsoft is actively developing a Direct Physics
application programming interface to complement the DirectX toolkit.
A job
on Microsoft’s website reads:

The Windows Graphics and Gaming Technology group is looking for a
software design engineer to join a growing team responsible for
developing Direct Physics. This team is responsible for delivering a
great leap forwards in the way game developers think about integrating
Physics into their engines. . . . You will be a member of the core
engine team who will be primarily responsible for working closely with
our Direct3D team, helping to define, develop and map optimized
simulation and collision algorithms onto data structures that are
optimized for the GPU.

The job posting dates back to August 2005, so a Direct Physics API could
be well underway by now.

Going by the mention of “data structures that
are optimized for the GPU,” it sounds like Direct Physics may be similar
to Havok’s Havok
API, which harnesses shader power on modern graphics cards for physics acceleration. ExtremeTech does point out, however, that Microsoft licensed Ageia’s PhysX SDK for an apparently unrelated robotics

Comments closed
    • Bensam123
    • 15 years ago

    Well I thought Ageia would have a chance against havok, ati/nvidia but now that Microsoft is in on it and the wide use and availability of DirectX it pretty much spells out Ageias future.

    Unless game developers like what Ageia is doing it’s pretty much the end.

      • UberGerbil
      • 15 years ago

      Not necessarily. The existence of a unifying API doesn’t require the death of dedicated hardware using another API: Aegia can certainly function using Microsoft’s API. It actually removes their burden of evangelizing game devs to use their API (and counter-evangelizing against the competing ones). Aegia’s problem has always been convincing game devs to actually explot physics in a way that makes the experience of gaming with a PPU much better than gaming without it — not just in terms of eye-candy, but in actual gameplay and gaming experience. That’s the only way to compell people to go out and buy a PPU. That problem doesn’t change, but a common API makes it more likely that the enthusiast (for now, the only people who might buy such a thing) will actually see some /[

    • evermore
    • 15 years ago

    Didn’t take that long for MS to decide to steal the physics companies’ thunder.

      • UberGerbil
      • 15 years ago

      Actually, historically this is exactly the role the HW companies have asked MS to fill (sometimes publicly, sometimes tacitly, but they’ve always at least privately acknowledged its value). Whenever there are two or more competing APIs to do the same thing, MS either annoints one as the standard or invents its own that everybody else supports “in addition to” their own proprietary one. Over time the MS standard generally prevails (because software developers know it’s the one that will work regardless of hardware), and the industry as a whole benefits. They did this with DirectX (back when Glide, OpenGL, and several other lesser 3D APIs were floating around and an even wider variety of sound APIs were trying to get traction), They did it with their TCP/IP implementation (does anybody remember the ugliness of incompatible TCP/IP stacks?). They did it with WiFi, and CD-ROMs, and a bunch of other things. In fact, that was one of the first advantages of Windows: universal printer drivers (instead of every application having to have its own)..

      I’ve been predicting this since Aegia first talked about physics hardware, and it’s a Good Thing. This makes it far more likely there will be other PPU implementations, and far more likely they will become cheap and common.

    • shank15217
    • 15 years ago

    The only real problem with the agiea;s solution is the latency in the pci bus causes realtime physics calculation to not make it in time for the card’s rendering. Agiea is begging for a pci express solution imho. I dont even understand why they used the pci card for such a powerful processor. These days pci busses are on the south bridge and have to traverse to the north bridge and then to the pci express bus. Latency is a killer for real time physics. Aegiea’s technology is great but their interconnect choice is bogus.

    Physics calculations go

    CPU -> MC athlon 64
    CPU -> Northbridge->MC pentium XX

    IRQ of some sort by the aegiea driver

    Aeigia -> Southbridge -> Northbridge -> MC

    then calculated results go back to the cpu

    which is then used by the game graphics engine to be sent to the GPU

    This is very simplistic but as you can see there is a lot of movement back and forth between the cpu and the PPU before it even gets to the GPU. This cant be good for calculating generally simple scenes that is more time bound that complexity bound. Infact with today’s Aiegia’s implementation I am sure their “Optimizations” are basically taking into accunt possible rount trip time from the CPU to the PPU compared to emulated results and just taking the first result available. CPUs doing the simple timebound calculations and the PPU doing the stuff that would take too long for the cpu to pull off in time for the graphics engine to render.

    • DrDillyBar
    • 15 years ago

    Now here’s how you get developers to take physics seriously. While it does sound like it’s going to be a more HavokFX based solution, I’m betting they also include a code path that notes the presence of the Ageia hardware. The Xbox 360 uses the Ageia API also, but optimized for the CPU’s structure, IIRC.

    • supercromp
    • 15 years ago

    so we get away from fillrate and increase pixel shaders a al 1900xt, now we are taking them and using them for physics?

    bad idea imo.

      • wierdo
      • 15 years ago

      Why? you prefer buying a phys card for $200?

      Personally I’m too budget conscious for that, so if someone finds a cheap – even if relatively crap – way of doing the same thing for now then that’s fine for me.

    • SpotTheCat
    • 15 years ago

    Direct PhysX anybody?

      • Arkham
      • 15 years ago

      (SpotTheCat FTW!)

      I expect a Havok buyout is next.

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