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Simulating fluids, fire, and smoke in real-time

andrewkchan.dev

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Re: Simulating fluids, fire, and smoke in real-time

#71

Post by softfalcon »

MaxBarraclough wrote: post #54
softfalcon wrote: post #34

Earlier quoted context omitted.

In high performance scenarios, the GPU is running full blast while the CPU is running at full blast just feeding data and pre-process work to the GPU. The GPU is the steam engine hurtling forward, the CPU is just the person shoveling coal into the furnace. Using the integrated GPU heats up the main die where the CPU is because they live together on the same chip. The die heats up, CPU thermal throttles, CPU stops eff…

Doesn't this assume inadequate cooling? A quick google indicates AMD's X3D CPUs begin throttling around 89°C, and that it's not overly challenging to keep them below 80 even under intense CPU load, although that's presumably without any activity on the integrated GPU. Assuming cooling really is inadequate for running both the CPU cores and the integrated GPU: for GPU-friendly workloads (i.e. no GPU-unfriendly preproc…

What the specs say they'll do and what they actually do are often very different realities in my experience.

I've seen thermal throttling happening at 60°C because overall, the chip is cool, but one core is maxing or two cores are maxing. Which is common in game dev with your primary thread feeding a GPU with command buffer queues and another scheduling the main game loop.

Even when water cooled or the high end air cooling on my server blades, I see that long term, the system just hits a trade-off point of ~60-70°C and ~85% max CPU clock even when the cooling system is industry grade, loud as hell, and has an HVAC unit backing it. Probably part of why scale out is so popular to distribute load.

When I give real work to any iGPU's on these systems, I see the temps bump 5-10°C and clocks on the CPU cores drop a bit. Could be drivers, could be temp curves, I would think these fancy cooling systems I'm running are performing well though. shrug

Re: Simulating fluids, fire, and smoke in real-time

#72

Post by tonyarkles »

dplavery92 wrote: post #53
llm_nerd wrote: post #8

Page is basically unusable on my Intel MBP, and still a beastly consumer on my AS Mac. I presume simulations are happening somewhere on the page, but it would be a good idea to make them toggled. Ideally via user interaction, but if one insists on auto-play when scrolled into the viewport.

I was encountering the same problem on my Intel MBP, and per another one of the comments here, find that switching from Chrome to Safari to view the page allows me to view the whole page, view it smoothly, and without my CPU utilization spiking or my fans spinning up.

Yeah, I just checked to see what this machine is... Mid 2015 15" Retina MBP with an AMD Radeon R9 and the page is buttery smooth in Safari.

Re: Simulating fluids, fire, and smoke in real-time

#73

Post by Sharlin »

FirmwareBurner wrote: post #62
Sharlin wrote: post #48

Earlier quoted context omitted.

> Guess the requirements in computer graphics are more inclined towards making something that looks right instead of getting the physics right. The first rule of real-time computer graphics has essentially always been "Cheat as much as you can get away with (and usually, even if you can't)." Also, it doesn't even have to look right , it just has to look cool! =)

Why not cheat? I'm not looking for realism in games, I'm looking for escapism and to have fun.

I didn't mean to imply that cheating is bad. Indeed it's mandatory if you want a remotely real-time performance.

Re: Simulating fluids, fire, and smoke in real-time

#74

Post by someletters »

digging wrote: post #67
FirmwareBurner wrote: post #62

Earlier quoted context omitted.

Why not cheat? I'm not looking for realism in games, I'm looking for escapism and to have fun.

I don't think this is a great argument because everybody is looking for some level of realism in games, but you may want less than many others. Without any, you'd have no intuitive behaviors and the controls would make no sense. I'm not saying this just to be pedantic - my point is that some people do want some games to have very high levels of realism.

Some of the best games I've played in my life were the text based and pixel art games in MS DOS. Your imagination then had to render or enhance the visuals, and it was pretty cool to come up with the pictures in your head.

Re: Simulating fluids, fire, and smoke in real-time

#75

Post by corysama »

Sharlin wrote: post #48
cherryteastain wrote: post #3

As a person who did a PhD in CFD, I must admit I never encountered the vorticity confinement method and curl-noise turbulence. I guess you learn something new every day! Also, in industrial CFD, where the Reynolds numbers are higher you'd never want something like counteracting artificial dissipation of the numerical method by trying to applying noise. In fact, quite often people want artificial dissipation to stabil…

> Guess the requirements in computer graphics are more inclined towards making something that looks right instead of getting the physics right. The first rule of real-time computer graphics has essentially always been "Cheat as much as you can get away with (and usually, even if you can't)." Also, it doesn't even have to look right , it just has to look cool! =)

> Also, it doesn't even have to look right, it just has to look cool! =)

The refrain is: Plausible. Not realistic.

Doesn't have to be correct. Just needs to lead the audience to accept it.

Yeah. And, cheat as much as you can. And, then just a little more ;)

Re: Simulating fluids, fire, and smoke in real-time

#76

Post by Philpax »

Sharlin wrote: post #48
cherryteastain wrote: post #3

As a person who did a PhD in CFD, I must admit I never encountered the vorticity confinement method and curl-noise turbulence. I guess you learn something new every day! Also, in industrial CFD, where the Reynolds numbers are higher you'd never want something like counteracting artificial dissipation of the numerical method by trying to applying noise. In fact, quite often people want artificial dissipation to stabil…

> Guess the requirements in computer graphics are more inclined towards making something that looks right instead of getting the physics right. The first rule of real-time computer graphics has essentially always been "Cheat as much as you can get away with (and usually, even if you can't)." Also, it doesn't even have to look right , it just has to look cool! =)

“Everything is smoke and mirrors in computer graphics - especially the smoke and mirrors!”

Re: Simulating fluids, fire, and smoke in real-time

#77

Post by russelg »

andygeorge wrote: post #57
llm_nerd wrote: post #8

Page is basically unusable on my Intel MBP, and still a beastly consumer on my AS Mac. I presume simulations are happening somewhere on the page, but it would be a good idea to make them toggled. Ideally via user interaction, but if one insists on auto-play when scrolled into the viewport.

Same hardware(s) as you, smooth and 0 issues. Pebkac

Both you and the GP failed to mention what browser you're using.

Re: Simulating fluids, fire, and smoke in real-time

#78

Post by mewpmewp2 »

someletters wrote: post #74
digging wrote: post #67

Earlier quoted context omitted.

I don't think this is a great argument because everybody is looking for some level of realism in games, but you may want less than many others. Without any, you'd have no intuitive behaviors and the controls would make no sense. I'm not saying this just to be pedantic - my point is that some people do want some games to have very high levels of realism.

Some of the best games I've played in my life were the text based and pixel art games in MS DOS. Your imagination then had to render or enhance the visuals, and it was pretty cool to come up with the pictures in your head.

I mean yes, but, ultimately we want to be able to simulate ourselves to the truest to be able to understand our origins, which are likely simulated as well, right.

Re: Simulating fluids, fire, and smoke in real-time

#80

Post by godelski »

cherryteastain wrote: post #17
jwoq9118 wrote: post #12

Earlier quoted context omitted.

Was the PhD worth it in your opinion?

From a purely economic standpoint, difficult to say. I was able to build skills that are very in demand in certain technical areas, and breaking into these areas is notoriously difficult otherwise. On the other hand, I earned peanuts for many years. It'll probably take some time for it to pay off. That said, never do a PhD for economic reasons alone. It's a period in your life where you are given an opportunity to bu…

> On the other hand, I also found out that academia sucks

I also found that I don't want to be a good academic, but a good researcher. Most importantly, that these are two very different things.

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