Video game development is expensive, but not because it's particularly difficult to implement simulations using fairly standard graphics or physics libraries like PhysX. If anything, having those simulations already done, ready to go, and built into the library you're using makes things cheaper, not more expensive since companies don't have to develop their own simulations from scratch anymore.blink said:
PhysX Real-Time Fluid Physics Are Crazy Realistic
- Thread starter Steven Bogos
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There was a really great 2D game that had amazing water physics that seemed to work like this. I can't remember what it was called, but it involved propulsion by vomiting.
So it can handle a bathtub load of simulated water. What happens if you try to make an area with a small lake, using this physics engine?
That's because it would kill everything at this point.weirdguy said:
It'll come along.
For instance, the music of the vid was from Mirror's Edge. Mirror's Edge had PhysX enabled in it, which added completely realistic glass shattering, cloth tearing and wind gusting that wasn't in the console versions. So by extension, we'll see this water become a common occurrence in the next couple years as well.
There's subtle differences. The water in your video looks like someone added cornstarch to it, for instance.Fluke said:
It's nice to see a thread that doesn't immediately descend into vilifying any and all attempts at making games that little bit more pleasing to look at.
For those asking about the maths, what makes this method interesting is that it's not a force-based method ? it's a position-based method. It doesn't use the Navier-Stokes method which is not a particle method and integrates convective forces over a fixed, static grid to get fluid motion (and is therefore pretty much useless for video games) and it's not another variant of the Smoothed Particle Hydrodynamics (SPH) method because it doesn't take the weighted force contributions from it's neighbouring particles (I believe the game Hydrophobia used a very coarse SPH-like simulation). Position-based methods directly estimate the new position at each time step from the previous step's particle velocity and then impose a set of constraints ? a much more stable method when you don't have that many particles. For those who really, really want to know about the maths: [link]http://mmacklin.com/pbf_sig_preprint.pdf[/link]
I don't think there's any danger of this method ever becoming the standard method of rendering water in games. 90% of the time you're not interacting with the water you see. The guy who will really win the cookie in the field of real-time fluid sims is the guy who can mix particle methods with typical mesh water surfaces on an 'as needed' basis.
TL;DR: The future is not the old method or this new method of doing fluids. It's a hybrid.
For those asking about the maths, what makes this method interesting is that it's not a force-based method ? it's a position-based method. It doesn't use the Navier-Stokes method which is not a particle method and integrates convective forces over a fixed, static grid to get fluid motion (and is therefore pretty much useless for video games) and it's not another variant of the Smoothed Particle Hydrodynamics (SPH) method because it doesn't take the weighted force contributions from it's neighbouring particles (I believe the game Hydrophobia used a very coarse SPH-like simulation). Position-based methods directly estimate the new position at each time step from the previous step's particle velocity and then impose a set of constraints ? a much more stable method when you don't have that many particles. For those who really, really want to know about the maths: [link]http://mmacklin.com/pbf_sig_preprint.pdf[/link]
I don't think there's any danger of this method ever becoming the standard method of rendering water in games. 90% of the time you're not interacting with the water you see. The guy who will really win the cookie in the field of real-time fluid sims is the guy who can mix particle methods with typical mesh water surfaces on an 'as needed' basis.
TL;DR: The future is not the old method or this new method of doing fluids. It's a hybrid.
You know, I have a secondary 400 series card alongside my GTX 680 DEDICATED to that shit. Nobody likes a 50% performance hit, after all. UNACCEPTABLE.
In games that have advanced effects, it is VERY nice to have (graphics whore here....)
It might also help if more than a couple of titles a year implemented PhysX in any meaningful way.
It's not even the consoles' fault(not SO much, anyway, though they're certainly not helping) rather that most people wouldn't be inclined to install a 2nd GPU to sort the physics calculations, or take the massive framerate hit instead.
Come at me, developers.....
If only it was that easy eh?.
In games that have advanced effects, it is VERY nice to have (graphics whore here....)
It might also help if more than a couple of titles a year implemented PhysX in any meaningful way.
It's not even the consoles' fault(not SO much, anyway, though they're certainly not helping) rather that most people wouldn't be inclined to install a 2nd GPU to sort the physics calculations, or take the massive framerate hit instead.
Come at me, developers.....
If only it was that easy eh?.
You seem to really know your stuff! I wonder what you think would make for a more efficient way to realisticly model fluids, this Navier-Stokes equation, or the method you (and I, as a matter of fact) think they have used in this example? I'd expect the Navier-Stokes equation as, from my position of nearly complete ignorance of the particulars, it seems it doesn't need to keep track of every particle.grigjd3 said:
I just wait... Eventually, the lovely PhysX effects can be handled by one good GPU, and my lovely 60FPS can be maintained.bobajob said:
It's cheaper that way.
I worked in numerical relativity as a graduate student and a post-doc which shares a great deal of math with and sometimes even incorporates fluid dynamics. I would guess that the Navier-Stokes equation is less efficient to use simply by the fact that these people decided to do things this way. I mean, I am not completely certain having never met this particular team, but I have met some of the people hired for this kind of work and they generally are well aware of the options available to them for computing strategies.dvd_72 said:
Yeah I can see where you are coming from on this. Looking at some of the videos posted it's impressive that we can produce environments of that calibre but in the end it might be to the overall game's detriment. However I feel that we will soon (When I say soon I mean another 5 years-decade) where we will finally get out of the uncanny valley and hit a graphical peak where developers can say "Well we could develop in a higher fidelity but what is the point other then as a marketing point". Once that happens the rest of the industry will catch up in terms of narrative and gameplay mechanics in an effort to keep up with the rest of the market and also the cost of graphics as a whole will get reduced as Nvidea and AMD will strive to make graphics cards which are more efficient as opposed to being able to output the highest graphical detail.blink said:
Though to say that there isn't any indie developers or developers which produce games that have a low graphics but high gameplay values isn't quite true. Just to name a few examples:
FTL
Any number of MOBA's (for me that mainly means League of Legends)
Dwarf fortress (Possibly one of the most complex games around)
Crusader Kings 2 (Or any other game made by Paradox Plaza really)
Mount and Blade
Day of the tentacle
The walking dead game
Any host of the more popular Visual novels (Though really this is more reading an interactive book then playing a game)
One special mention I would like to make goes to Bethesda for being the kings of "OOH THAT LOOKS PRETTY FROM A DISTANCE" and then on closer inspection the textures look like crap but because of this it has some absolutely stunning scenery and is also playable on lower end machines that use graphics cards from 5 years ago that weren't even designed to be top of the line then (GT 210 512MB for example).
In summary I can understand the hesitancy to over focus on graphics and not donate enough time to other parts of the games but like I have said give it little while and the focus will eventually shift off of that and move onto the other, and in my opinion, more important aspects of gaming.
The things this tech could add too if paired with people with inventive uses for it in games,assuming they can do it.
makes me think of what you could use water for in Bioshock.
still chances of seeing this in games in the near future are pretty slim due to hardware limitations like everyone said before me, and then i get thoughts of people making games where they overdo this tech to compensate for things they are lacking in the game itself or try to use it as a selling point, maybe I'm just being to pessimistic about where publishers will take this.
makes me think of what you could use water for in Bioshock.
still chances of seeing this in games in the near future are pretty slim due to hardware limitations like everyone said before me, and then i get thoughts of people making games where they overdo this tech to compensate for things they are lacking in the game itself or try to use it as a selling point, maybe I'm just being to pessimistic about where publishers will take this.
It still looks deeply nestled in the uncanny valley of water. Once they get it to look like it's not made of tens of thousands of balls a Jell-O, That's when I'll be impressed.
Little details like realistic water are nice and all, but I'd happily give that up for streamed code and additional bug testing (yes, I know these guys don't make the games).
Little details like realistic water are nice and all, but I'd happily give that up for streamed code and additional bug testing (yes, I know these guys don't make the games).
I don't know. I'd say when you're actually immersed in the fluid, the motion probably doesn't need that much attention to physics. >.>Steven Bogos said:
The only problem with these physics is the water does not have weight, so it does not push anything. That's why it kept getting stuck in the glass when it kept forming closed containers by accident. In real life, the shards would be pushed aside because they're not actually connected and can't keep the water in place, but in the demonstration, the water simply conformed.
That's easily fixed, though.
The only problem is now that PhysX is ahead of OpenCL. if I want to experience realistic water, I have to get an Nvidia card.
That's easily fixed, though.
The only problem is now that PhysX is ahead of OpenCL. if I want to experience realistic water, I have to get an Nvidia card.
It's cool, but these tech demos for water always feel off to me. I think the viscosity is too low, or something.
One of the main benefits of this kind of tech isn't so much the quality or realism so much as the ability for designers to iterate faster.blink said:
Instead of having to precompute waterfalls and splashes and spend a whole bunch of time simulating/rendering/baking/etc, the developers can just do it all in real-time and spend more time making it look good and behave correctly, spend more time on the stuff that matters.
Instead of having to spend a bunch of time coming up with smoke and mirrors to make a corridor flood in Bioshock, they could just do it with real-time simulations and just be done with it, with the added bonus of letting the player be able to interact with it.
Or what about in a game like Half-Life 2, the fluid simulations could drive the physics, water washing away debris and corpses and stuff like that, have the boat be affected by waves, water physics puzzles, etc. Right now all those things have to be faked, and faking them correctly takes a lot of time.
Not to mention the fact that this same tech can be used for other things too, like lava simulations, smoke simulations, etc.
Now obviously these examples are larger in scale but it's only a matter of time. To say that all we're going to get is prettier water is a very narrow view when this is the kind of tech that entire games can be based on. Games which are impossible today, but quite possible in a near future. What's the hardware going to be like when the GTX Titan or GTX 690 eventually become low-end $100 GPUs?