What kind of Calculations Does PhysX Use?

[bore_u2_death]

Hey guys, I know that faster PPUs increase performance, but what calculations does PhysX use, so that when a GPU can do more of those, it functions better as a PPU?

For example, if arithmetic is what a GPU uses for PhysX, would higher GFLOPS be what decides a PPUs performance?

 

[christianw]

floating point operations

 

[bore_u2_death]

Thank you.

 

[serpretetsky]

i once had a customer come in to the store and blatantly ask which computer would do the most floating point operations per second. I didn't really know the models we had out on the floor or what his exact use for it was. So i just said probably the one with the fastest video card.

He told me video cards dont do any floating point operations.
I stayed silent
he left the store
that was the end of that.

 

[bore_u2_death]

i once had a customer come in to the store and blatantly ask which computer would do the most floating point operations per second. I didn't really know the models we had out on the floor or what his exact use for it was. So i just said probably the one with the fastest video card.

He told me video cards dont do any floating point operations.
I stayed silent
he left the store
that was the end of that.

I hope the guy wasn't expecting too much. Your only human, the internet is a far better source for information like that.

 

[cmay119]

i once had a customer come in to the store and blatantly ask which computer would do the most floating point operations per second. I didn't really know the models we had out on the floor or what his exact use for it was. So i just said probably the one with the fastest video card.

He told me video cards dont do any floating point operations.
I stayed silent
he left the store
that was the end of that.

I'm not too informed on the calculations of FLOPS, but weren't you correct in your answer? I was under the impression that a GPU can do more Floating Operations in a Second than a relative CPU can?

It's funny, I've been into building computers for a long time now, but when I get down to the actual math & science behind the hardware, I'm a complete bonehead, hehe.

 

[serpretetsky]

straight from the most trusted source of information, wikipedia:

Graphics processing unit (GPU)
Main article: Graphics processing unit
A GPU is a dedicated processor optimized for accelerating graphics. The processor is designed specifically to perform floating-point calculations, which are fundamental to 3D graphics rendering.

Floating Point operations is a really generic term, it means any mathemtical procedure involving floating point numbers (which are basically values represented in scientific notation).

 

[Crispy002]

The actual calculations they're doing should follow the generic equations for whatever needs to be calculated. Fluid dynamics equations for fluids and smoke particles, kinematics for solid objects, and I'd suspect some combination of the two for cloth effects. Due to the incredibly large amount of data that has to be worked out, the coders probably (hopefully, for their sanity) put everything into matrices. Summarized, the PPU ends up doing vector math using matrices with floating point numbers.

I don't know this for sure, but it is a well educated guess.

 

[Trogdor2012]

The actual calculations they're doing should follow the generic equations for whatever needs to be calculated. Fluid dynamics equations for fluids and smoke particles, kinematics for solid objects, and I'd suspect some combination of the two for cloth effects. Due to the incredibly large amount of data that has to be worked out, the coders probably (hopefully, for their sanity) put everything into matrices. Summarized, the PPU ends up doing vector math using matrices with floating point numbers.

I don't know this for sure, but it is a well educated guess.

You're probalbly right, if not, I am sure you're very close.

The one caveat I'd like to add is that coders also cheat. If they find that the amount of processing power needed for cloth/smoke/water/whatever effects is too much they will come up with a pre-made animation that may be enhanced with a small amount of real physics, but not be fully created with physX.

Most users wont notice the difference. We've lived with canned animations for nearly everything since forever, and sadly, no game maker has pushed PhysX far enough for us to open our eyes.