PhysX

[RSF TheCapulet 59]

I haven't read through all 55 pages of this thread to see if someone had posted this before, but I found this and thought it could come in handy, should BIS use some GPU-based Physx features.

How To Run Physx On an ATI GPU on Windows 7

You should rename your link to "How to run PhysX on an Nvidia card, with an ATI card as the main GPU".

And a better link to better drivers, instructions, etc for this:

http://forums.guru3d.com/showthread.php?t=322616

[Brainbug 10]

Well the problem with PhysX is that it is a proprietary means from one hardware producer to better sell their hardware. If you use a physics engine that uses the OpenCL API, then it could run on whatever hardware is best suited in regards of performance. But PhysX has not the best performance as a goal, it's goal is to sell Nvidia hardware. So Nvidia disables execution on AMD hardware (some hacks proved that a Radeon can run it, but those driver hacks are being battled by Nvidia, so it is probably not a solution to set confidence into) and also cripples execution in CPUs in order to make CPUs appear much slower than they could be.

That means the argument "bah, Radeon users still can use their CPU for PhysX" is invalid, because you can never squeeze out the same performance from the fastest CPU money can buy if the PhysX engine is purposely crippled to be substantially slower than a Nvidia GPU (if Intel puts out a new CPU with ten times the power, Nvidia would cripple their software even further to keep the distance).

And I REALLY hate being FORCED onto something. The choice here is to either buy no ARMA3 (unthinkable for me), or play it with crappy performance and disabled features (woohoo, fun), or do what Nvidia wants me to do and buy their stuff (gladly. NOT). Which is no real choice, is it.

You know, when a woman is being forced to have sex with someone, then you call it rape, and it still stays that even if you bring up the argument "but that guy looks like George Clooney, don't make a fuss". So I don't want to hear the argument "Nvidia builds the better graphics cards anyway". That might be true or not (usually changes every year with every new generation of cards) - but I want to DECIDE FOR MYSELF on what I buy. Otherwise I also feel slightly raped.

I know that Nvidia writes quite comfortable developer tools for PhysX as incentives (besides money) for developers to use their product even if they know that it is not the best choice for their customers. Some would call it corruption, others a smart investment by Nvidia. I'm really sad to read that "our" Bohemians also took the path to the dark side, I really didn't think it would come that far.

As long as the game only uses a minimal amount of physics calculations, a difference in performance is certainly negligible, so a studio can just rake in the money from Nvidia and still don't put their customers at a disadvantage. But the Arma series is much more demanding and most of the time people spend with it are not in the vanilla campaign missions but in customised missions, so you can't estimate in advance the amount of physics used. If physics where accelerated by hardware properly on ALL computers, then you could use it extensively. But if it is not and would make a heavily "physicalised" (it that a word?^^) mission unplayable for half the people that play the game, then the mission or addon maker is forced to just use a minimal amount of it.

That just slows down the development of the game series as a whole. And it kills game sales: If Radeon users (wo are new to the game and just saw a few screenshots and are interested) read that they would need to buy other hardware to run this game properly, they are turned off and just look for other games. I doubt that any Nvidia money can balance that loss in potential sales.

I'd really like to hear that a different approach is being taken (read OpenCL physics), but of course I have no influence on that and it probably is way to late anyway to change anything. So I think I'll prepare myself mentally and get some vaseline.

Edited August 25, 2011 by Brainbug

[dm 9]

Oh look, its this rant again.

Since Pettka has confirmed that they're not using the hardware accelleration of physX, your entire rant, and your "oh noes, I cant use all the physX features!11!1!!1!" is not only untrue, but hugely uninformed.

[Leon86 13]

Indeed, thread is going in circles. If you want to use some physics middleware you basically have the choice between havok and physX. Bis already has experience with physX so obviously they're using that. There are many games that use physX but only a few that use hardware accelerated physX, arma 3 will probably not be one of them.

[metalcraze 290]

People are uninformed in that they think that hardware accellerated PhysX will stop the game from working normally on ATi cards which is a huge facepalm.

I'm really disappointed there will be no hw PhysX. Could've saved quite a few FPS.

[PuFu 4600]

People are uninformed in that they think that hardware accellerated PhysX will stop the game from working normally on ATi cards which is a huge facepalm.

I'm really disappointed there will be no hw PhysX. Could've saved quite a few FPS.

You seem just as uniformed as the those people you just talk about. Facepalms everywhere

[dmarkwick 261]

If PhysX calculations can be farmed out to it's own core, that should make it very efficient. Plus, you never know, HW patch might appear sometime in the future as a little gift for nVidia owners... ;)

[NeMeSiS 11]

As an Ati user, and not a big fan of PhysX, i am also somewhat dissapointed by the fact that apparently there is going to be no hw acceleration at all, not even for nVidia users. Is there a reason for this? Too hard to implement properly before release?

[Leon86 13]

Enabling hardware acceration is extra work. It's only on vehicles anyway, a cpu is easily capable of doing the calculations. And it should be if ati users are to have a good expierience. The only way to really make use of physX is optional eyecandy and I dont think Bis will waste their time on that.

[PuFu 4600]

besides, as i previously stated, HW acc PhysiX i have seen so far covers ONLY the cloth and particle simulations, not the rigid bodies and ragdolls

[Leon86 13]

Well, it might hardware-accelerate the other things as well, just not noticable because its so little work it makes no difference if the cpu does it.

I did a small test with my i5-750 @ 4Ghz and 2x gtx260 with the mafia II demo, physX on high. That's with cartoonish ammounts of particles flying around.

PhysX on cpu: 18 fps

PhysX on on gpu that renders: 31 fps

PhysX on dedicated gpu: 35 fps

Sli and PhysX on "slave" gpu: 33 fps.

Sli and PhysX on master gpu: 37 fps.

At first you may say, see cpu PhysX sux. But with all those particles flying around the game apparantly becomes cpu limited even with all the PhysX on the gpu's (no real gain in sli compared nonsli+physX on gpu1). These pieces of concrete have 6 degrees of freedom(3 positions + 3 angles). Lets say an arma vehicle has 4 wheels so that's 6 (same)+2x4 (distance to body and rotation)=14 degrees, of course collision might be a bit more work but I doubt its more PhysX work than 4-5 small pieces of concrete.

An arma vehicle has many, many more polygons (=big cpu load) than the mafia pieces of concrete. You're bound to become cpu limited much earlier with these polygons than with physX code on the cpu.

medium physX and detail object detail:

cpu physX: 30 fps

gpu physX: 40 fps

no physX: 80 fps

Edited August 25, 2011 by Leon86

[neokika 62]

What game you talking about Leon86?

I see, Mafia 2.

APEX is different then PhysX, basically, in Mafia 2 you cannot turn of PhysX, that handle stuff like Animations, Rag-doll and vehicle/object collisions, you can only change APEX values.

APEX in Mafia 2 is for Cloth and 3D particles only, so that benchmark is wrong in every way.

Arma 3 developers didn't mentioned APEX, but only PhysX, so I think its safe to assume that APEX is not going to be included.

For a correct benchmark you should turn of APEX completly and do CPU and GPU tests.

_neo_

Edited August 25, 2011 by neokika

[roberthammer 582]

Leon that only applies to Mafia 2 , ArmA 3 won't have amounts of particles flying around or Cloth - so it won't eat that much FPS

ArmA 3 will use it only for ragdolls and basic game physics

[Leon86 13]

Well the other part probably isnt even hardware accelerated to begin with. And no difference in the benchmark.

Edited August 25, 2011 by Leon86

[PuFu 4600]

]Well the other part probably isnt even hardware accelerated to begin with[/b]. And no difference in the benchmark.

That is the point ppl should understand, so this ATI vs Nvidia thing can stop: there is no hw acc for the damn rigid bodies and ragdolls!

[NeMeSiS 11]

besides, as i previously stated, HW acc PhysiX i have seen so far covers ONLY the cloth and particle simulations, not the rigid bodies and ragdolls

Makes sense, thanks for the info.

[4 IN 1 0]

This is what makes me dislike all these HW acc thing the most, as there is no real attemp to use GPU acc for more complex "basic" physics, thats makes all this HW acc thing quite pointless.

[twisted 128]

To be fair, I just played a rather taxing ArmA2 scenario that dragged my FPS down, and yet my CPU is less than 25% utilised. I assume this to be because of unused threads. So if the PhysX can work in its own thread, there would be no impact on performance at least on my machine.

possibly the most interesting point on this whole page for me.

:292:

[gL33k 0]

physx + vertex deformation (on vehicle , metal door etc ) should be thinked .

[soldier2390 0]

Question for a Developer!

This is the first time I really heard any thing about Physx before, and i have a few questions? In some games, like Tier 1 for example, gear on soldiers move independently from the soldiers model its self..which is very realistic! I.e. "ButtPacks" on soldiers can move and sway, where as in Arma2/OA they are "Stuck" to the model, and when a soldier is on his back or in a certain possition the "ButtPack" is either throw the ground/soldier model, but in some games it seems to have its own RL Physics, making the soldiers model in a sence move around the model...as in RL same goes for Rucksacks, when ever i slept on my back with my rucksack on during a training op or whatnot, do to RL Physics my back was off the ground, but in Arma2/OA the soldiers back in flat on the ground, and the Rucksack is in the ground lol, but in other games like Tier 1, the Soldiers lay realisticly...Is that because of PhysX?

Other question is does anyone know if Arma3 will have this realistic Feature? And another question is what is that "Feature" called and how is it made, why is it not already in Arma2/OA?

Dave,

[purepassion 22]

@soldier2390

What you described is mostly just an animation and not real calculated eg cloth simulation.

it is possible in the game but would honestly not justify the amount of work

still i would really welcome if certain parts of models (especially antennas on vehicles) could get simulated via PhysX

[soldier2390 0]

@soldier2390

What you described is mostly just an animation and not real calculated eg cloth simulation.

it is possible in the game but would honestly not justify the amount of work

still i would really welcome if certain parts of models (especially antennas on vehicles) could get simulated via PhysX

Thanks for the aanswer PurePassion! Really appreciated, however I do feel as if would justify the amount of work...if done right and on the correct objects! ;)

I think it would add a new level of realism and realistic detail that IMHO would immerse the player into the game more, I rarely like to say anything about what this game should be, or be the one who acts like it should be done a certain way just for my own entertainment,however I felt as if I needed to say something because unlike most games this is more of a simulator or close enough to it and I believe that's why many of us who are on here and continually played theses games since ofp are still here, and I am one of them! I just would really like to see this feature added I think it could do more good then harm.

Anyways thanks for the answer, really helpful! Hopefully Dev's would deside to add this in!

Dave,

[wolfbite 8]

Hey soldier... It would be a bice feature in some ways.... But I imagine something like that would use up a lot of CPU cycles aespecially if you have hundreds of units in game... Ultimately it is a non essential cosmetic upgrade that would use loads of cycles to calculate..

[dmarkwick 261]

Hey soldier... It would be a bice feature in some ways.... But I imagine something like that would use up a lot of CPU cycles aespecially if you have hundreds of units in game... Ultimately it is a non essential cosmetic upgrade that would use loads of cycles to calculate..

... unless PhysX could be developed to use it's own CPU core? Plenty of users have unused cores while playing ArmA.

[maddogx 13]

... unless PhysX could be developed to use it's own CPU core? Plenty of users have unused cores while playing ArmA.

Or just add an option to enable/disable such cosmetic stuff and let it use the GPU. ;)