PhysX analyzed on CPU

[Hell Hound]

Wizzard Scientific supercomp's are built for accuracy @ a nice speed.Accuracy as is really all that they need,but since ipc keeps getting faster they upgrade to get ACCURATE RESULTS FASTER.

Dahma Wrong physx has 64 & 128 bit instruction

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[EnJoY]

then you shouldn't use a computer. it only works because it trades accurate results for faster results

God I love your posts.

[Hell Hound]

Tell that to the PENTAGON!!!!

[Iconyu]

Am I allowed to report posts for lowering the average IQ of the forum? Once upon a time I believed in the right of everyone to share their opinion, but seriously the more idiots I meet the less I want to hear.

[Hell Hound]

Yeah like accurate results are not needed for positional data when launching projectile's(missile's).To chose faster w/errors over Accurate results,That's dumb people faster is good but accuracy should not be sacrificed for it.We are talking scientific calculation's here which physics is,I'll take the slower more accurate path,while you all take the faster path yet you miss your target.

[buff]

Why has it dropped? Because NVIDIA didn't optimize PhysX for SSE? So you could troll this thread with pointless off-topic drivel?


Amorphous

Nvidia's constant game with "Physx won't work properly with Ati cards running graphics so we purposely disabled it"

Has turned people off from buying Nvidia. I've owned cards from both sides over the years, and yes I loved my G92, but this isn't the only area where Nvidia marketing has cheated consumers. I remember the FX series driver cheats with futuremark. Nvidia disabling Physx on the ppu since its "old". Making it run slower on cpu's so we want to buy more Nvidia cards to run physx. It gets old after awhile.

Obviously Nvidia is doing something wrong as their stock has plummeted. I used to own their stock and am really glad I ditched it.

[kl0012]

Wizzard Scientific supercomp's are built for accuracy @ a nice speed.Accuracy as is really all that they need,but since ipc keeps getting faster they upgrade to get ACCURATE RESULTS FASTER.

Dahma Wrong physx has 64 & 128 bit instruction

Thats about 64/128 bit SIMD writes/reads and not about the instruction precision.
Any way 32 bit precision is enough for a game physics. BTW, using SSE1/2 SP instructions CPU may be up to 4x faster per thread then when x87 is used.

[Chumbucket843]

Yeah like accurate results are not needed for positional data when launching projectile's(missile's).To chose faster w/errors over Accurate results,That's dumb people faster is good but accuracy should not be sacrificed for it.We are talking scientific calculation's here which physics is,I'll take the slower more accurate path,while you all take the faster path yet you miss your target.

1. even simulations on supercomputers are relatively innaccurate. computational physics has advantages because you can observe/measure with out disturbing the simulation. even with the computing power we have today it is just an aid to real world testing.

2. you are forgetting that this is real time. that means 17 milliseconds to compute everything. if you were to choose accuracy over speed then games would look terrible.

Thats about 64/128 bit SIMD writes/reads and not about the instruction precision.
Any way 32 bit precision is enough for a game physics. BTW, using SSE1/2 SP instructions CPU may be up to 4x faster per thread then when x87 is used.

actually speed ups of up to 20x are possible. the flat register model, cacheability instructions, and the ability to stream data make SSE very fast. it requires a lot of expertise to get code that fast but so does gpgpu.

[Xoulz]

Article confirms that on a modern 6-core proccesor, there is no need for GPU physics... that includes Nvidia now defunct physx.

[Hell Hound]

With all the pci-e slots we have we can afford to use more dedicated ppu's.Graphics is not really moving forward graw 2 looks like bc2.

[Xoulz]

With all the pci-e slots we have we can afford to use more dedicated ppu's.Graphics is not really moving forward graw 2 looks like bc2.

??


You mised the point. There is no need. Physics can be rendered on their own cores. 6-core cpu's cost less than an entire video card.

Do you understand?

[Hell Hound]

A 32 core gpu only cost $40 usd and we have not nearly used physx/physics like we could.

[Carfax]

Physx is over, more and more developers are moving to Havok for their game's physics.

LOL, which is why two big 2010 releases like Mafia 2 and Metro 2033 utilize hardware PhysX And those are just the hardware PhysX titles, and not software.

You don't have a clue..

Also, even though the article makes the case that better optimization would undoubtedly lead to better physX performance on the CPU, it still doesn't mean that the CPU could ever equal the GPU when it comes to processing physics algorithims.

Case in point, there is no software physics game that equals what you can find in hardware physics titles. A title like Mafia 2 features realistic cloth simulation (without the use of scripted animation), as well as advanced particle effects that use tens of thousands of particles for explosions and environmental destruction; far more than a CPU could handle in real time..

The fact is that the GPU will always be superior to the CPU in this regard, regardless of the amount of optimization on behalf of the CPU.

GPUs are naturally suited to that kind of computation, and when you look at it from a cost/performance perspective, the GPU easily takes the number one spot.

[Final8ty]

LOL, which is why two big 2010 releases like Mafia 2 and Metro 2033 utilize hardware PhysX And those are just the hardware PhysX titles, and not software.

You don't have a clue..

Also, even though the article makes the case that better optimization would undoubtedly lead to better physX performance on the CPU, it still doesn't mean that the CPU could ever equal the GPU when it comes to processing physics algorithims.

Case in point, there is no software physics game that equals what you can find in hardware physics titles. A title like Mafia 2 features realistic cloth simulation (without the use of scripted animation), as well as advanced particle effects that use tens of thousands of particles for explosions and environmental destruction; far more than a CPU could handle in real time..

The fact is that the GPU will always be superior to the CPU in this regard, regardless of the amount of optimization on behalf of the CPU.

GPUs are naturally suited to that kind of computation, and when you look at it from a cost/performance perspective, the GPU easily takes the number one spot.

He said more & more developers are moving to Havoc, he did not say all of them.
Stop seeing everything in absolute back & white.

And 2 games big deal & Metro 2033 was not all that at all so that's 1 too tick off.
And every big game that has GPU Phyxs in it is because NV have paid them to use it & not because the developer thought lets use it.

All the rest what you have posted is true but at the same time you have totally missed the points that people are making.
No one is saying that the CPU will ever equal the GPU possibility's for physics & none ever did, but the GPU is not need for every physics implementation as the CPU is up to doing the job.
Bring up the GPU can do it better is wearing thin because we all know that already & is a different argument, the problem is falsely making out that the CPU cant do any physics is what the discussion is about.

[Manicdan]

hopefully with opencl, you wont have to choose gpu or cpu, and whichever is not maxed out will be able to run the physics

[Hell Hound]

Then games will be limited because cpu will be bottleneck for anything more,depends on what is being simulated.Military fps is no go zone for cpu physx if you want realistic simulation,unless you have a qp board with HT enabled cpus.

[Final8ty]

Then games will be limited because cpu will be bottleneck for anything more,depends on what is being simulated.Military fps is no go zone for cpu physx if you want realistic simulation,unless you have a qp board with HT enabled cpus.

And how many Military simulations use GPU physx..exactly.

GPU physics will come when the developers feel a need for it.

And is no different from developers making the best use of QuadCore CPUs even tho they have been around for more than long enough & making the best use of the latest DX.
The best looking games that i have seen are still Dx9 even tho more powerful DX versions are available for them to use..

[AndrewZorn]

Well physx has to be as accurate as possible so More precision is better,I wouldn't trade accurate results for faster results ever,I repeat EVER.

Saw this thread, was hoping this guy would be in here. I didn't read the actual details or anything, but I'm content now.

[Carfax]

Bring up the GPU can do it better is wearing thin because we all know that already & is a different argument, the problem is falsely making out that the CPU cant do any physics is what the discussion is about.

The article implies in a none too subtle manner that a CPU (when properly optimized for) can match or come close to a GPU, which is incorrect.

If adherence to reality is the ultimate barometer and target for game physics (much like graphics), then the CPU presently just doesn't have enough power to run the advanced physics effects required for modern day gaming.

Which is why I don't see why so many people attack Nvidia for emphasizing physics on the GPU, and not the CPU.

It's just the natural evolution that makes the most sense..

[cegras]

The article implies in a none too subtle manner that a CPU (when properly optimized for) can match or come close to a GPU, which is incorrect.

If adherence to reality is the ultimate barometer and target for game physics (much like graphics), then the CPU presently just doesn't have enough power to run the advanced physics effects required for modern day gaming.

Which is why I don't see why so many people attack Nvidia for emphasizing physics on the GPU, and not the CPU.

It's just the natural evolution that makes the most sense..

What kind of level of physics are you talking about? You can just arbitrarily set the bar high enough that you'd want dust storms of individually simulated particles, which would mean a GPU.

But the level of physics offered by Havok is more than enough. Trying to calculate everything dynamically just because you can does not make it the best solution.

[Hell Hound]

In my eye's it does.

[Final8ty]

1)The article implies in a none too subtle manner that a CPU (when properly optimized for) can match or come close to a GPU, which is incorrect.

2)If adherence to reality is the ultimate barometer and target for game physics (much like graphics), then the CPU presently just doesn't have enough power to run the advanced physics effects required for modern day gaming.

3)Which is why I don't see why so many people attack Nvidia for emphasizing physics on the GPU, and not the CPU.

4)It's just the natural evolution that makes the most sense..

1) The article does not imply that, what it implies is that in some situations the CPU would be up to the job of doing what phyxs is doing in particular games if it were not for the CPU crippling.

2) Is your opinion because there is not an attempt at this present time to do anything what you have said so the CPU is up to the task of what's needed today.
And the fact is you wont see anything in the near future until the Consoles can do GPU physics as well & NV GPUs will most likely not be in the next ones.

3) The reason why is because of 1 & 2 & the fact is they are exaggerating things with crippling & they are not emphasizing physics on the GPU as a whole they are emphasizing Phyxs only for there GPU only which is a contradiction of trying to move the PC gaming platform forwards when it can only be run with one vendor.

4) If it was natural then NV would not need to keep paying for it to be used in games.

[Manicdan]

i find it funny that people complain about multicore scaling being horrible for games.
then want 8 core cpus for 100$.
then dont want physics on their cpu cause somehow its better to buy a 100$ gpu that only works on 1/3 of the games out there and can be done most of the time with the CPU

[Carfax]

What kind of level of physics are you talking about? You can just arbitrarily set the bar high enough that you'd want dust storms of individually simulated particles, which would mean a GPU.

But the level of physics offered by Havok is more than enough. Trying to calculate everything dynamically just because you can does not make it the best solution.

There is no specific level of physics, but game physics is similar to 3D graphics in how it perceived by gamers. The closer it is to reality, then the more impressive it becomes.

Just as developers strive to make their graphics more realistic, so should they strive to make their physics more realistic as well.

Unfortunately, adherence to reality requires LOADS more computation, and presently, the CPU is very inferior to the GPU in that regard.

You say Havok is sufficient for most physics, but the most commonly touted Havok game (BFBC2) doesn't even use Havok completely for it's most impressive physics effects.

Instead, it uses a combination of scripted animation (which has been around for years) combined with Havok to render the impressive explosions that you see in the game.

Thats all fine and good if you want to be stuck in the past, but technology like Time, doesn't stop for anyone.

With hardware PhysX, not only do we get a greater level of realism, but because developers no longer need to spend time animating effects that can now be run in engine and in real time, development time and cost are reduced.

With that said, the case for hardware accelerated physics is quite strong imo.

[Manicdan]

all this talk about GPU physics are a must, and yet all physics ive seen ingame suck (unless its a demo for something that we will never get anyway)