Archive for the ‘Articles, Reviews’ Category
Finally, NVIDIA has officially presented their new GPU – GTX 680, built on 28nm GK104 chip, which itself is based on next-gen Kepler architecture.
Many rumors were floating around Kepler and its physics acceleration capabilities, some were endowing new GPU with dedicated PhysX blocks, others were claiming ability to run CPU PhysX games in hardware – none of this happens to be true. Nothing special (like NVENC video encoder) for physics calculations, just general improvements to chip architecture, SM clusters, etc.
Nonetheless, we will try to gather all available information regarding PhysX computation performance of the GTX 680, in comparison to previous generation GPUs.
Interesting results – in this case, GeForce GTX 680 performance is higher than Radeon HD 7970 even with GPU PhysX effects enabled. However, we can not directly compare GTX 580 and GTX 680 due to different resolution settings.
Certainly, many of you will agree that the addition of GPU PhysX effects to PC games has a positive influence on overall gaming experience and immersion in such titles. But how difficult is to attach hardware accelerated physics effects to a game?
Today, with the help of David Schoemehl, Manager of GPU PhysX Content in NVIDIA, and Johnny Costello, Technical Artist, we will try to give you a brief “behind the scenes” view on the process of enhancing games with extra PhysX content.
PhysXInfo.com: Hi, Johnny and David. Can you please introduce yourself?
Johnny Costello: My name is Johnny Costello, I’m 29 years old and am a native to the Midwestern United States. I went to college at Savannah College of Art and Design and received my B.F.A. in game development. I have been a technical artist at NVIDIA for about two and a half years. During that time I have worked on several GPU PhysX titles such as Batman: Arkham Asylum, Batman: Arkham City, Mafia II, Dark Void, and Alice: Madness Returns.
David Schoemehl: My name is David Schoemehl, I joined AGEIA in 2006 as an applications engineer and was the project manager on Warmonger. Since the purchase of AGEIA by NVIDIA in 2008 I have led or supported several shipping GPU PhysX titles and demos including Batman: Arkham Asylum, The Samaritan Demo, Sacred 2, The Great Kulu Demo, and Alice: Madness Returns.
My current title is Manager of GPU PhysX Content and I am responsible for aligning NVIDIA’s engineers and artists to support developers on GPU PhysX engagements. I also work closely with Epic Games to ensure a solid integration of GPU PhysX/APEX features in UE3.
PhysXInfo.com: Johnny, what is your task as a PhysX technical artist?
Johnny Costello: My tasks can change a lot from day to day, but usually I’m working on a game title in some capacity. Our goal at NVIDIA is to provide the tools that developers need in order to add great GPU features to their games. So I spend much of my time working with developers to help guide them as they use our technology to create exciting content.
Depending on the structure of a particular engagement I may also work alongside the developer to create GPU PhysX content. Then there are other days where I help design and review our tools and production workflows.
It is time to summarize what PhysX Technology has achieved in year 2011, recall the most memorable events and releases.
GPU physics acceleration still can not gain enough momentum – only two games with support for GPU PhysX effects were released this year, this is the lowest result since Ageia was aquired.
One may call this an agony, but NVIDIA has told us that it was “conscious decision” – time was taken to develop and improve underlaying technology (PhysX SDK, APEX, DCC tools), thus sacrificing ability to create content and integrate it into many games.
It was promised that we will see “more GPU PhysX games next year than you did this year” and even “a lot more in 2013″.
Meanwhile, both GPU PhysX titles released this year were pretty interesting by themselves:
- Batman: Arkham City, one of the best games with hardware PhysX support.
- Alice: Madness Returns, which is a decent game too and is certanly worth more than two Darkest of Days.
Time to update PhysX performance metrics of NVIDIA GPUs with newest title with Hardware PhysX support – Batman: Arkham City.
In following article we’ve tried to gather all the benchmarks and tests, published on the web.
[25.11.2011] Batman Arkham City im Technik-Test: Grafikkarten-, DirectX-11- und Physx-Benchmarks by PCGamesHardware.de
German article with graphics benchmarks, overview of DX 11 and PhysX features, and a superficial PhysX tests.
Batman: Arkham City tests the patience of PC gamers with several release delays, but will try to wheedle them with DX 11 Graphics and PhysX Technology.
Update: GPU PhysX in Batman: Arkham City - review and comparison video.
Recent comparison trailer gave us a glimpse of extra physics effects, and now we want to provide you with some additional details on what to expect from GPU PhysX content. In addition, new comparison PhysX video was released as well.
As usually, it will be possible to adjust level of in-game physics via “Hardware Accelerated PhysX” option in game’s launcher. There will be three settings:
PhysX Off: all GPU accelerated effects are disabled, only standart CPU physics (like ragdolls) is used.
PhysX Normal: enables additional particles effects (debris, volumetric smoke and steam, etc) and destructible environments.
PhysX High: includes all effects enabled withing “Normal” settings as well as realtime cloth and clothing simulation.
Earlier this year, Matthias Müller-Fischer, PhysX SDK Research Lead in NVIDIA, has presented new universal solver that can be used simulate almost any kind of objects – rigid, plastic, cloth or soft body.
You can familiarize with this work via previously published research papers: Solid Simulation with Oriented Particles and Adding Physics to Animated Characters with Oriented Particles.
Today, interesting video was revealed – it is showcasing impressive 20x performance improvement for this type of simulation running on GPU through CUDA, in comparison to CPU execution (5 “Lionfish” objects on CPU vs 100 on GPU – in real-time).
Sometimes findings of PhysX Research team are incorporated in PhysX/APEX products, and sometimes, for various reasons, they just become a research paper or presentation. We hope that in case with solver there will be only one option – first one.
Metro: Last Light, sequel to Metro 2033 title, is aiming technology throne with DX 11, tesselation and support for GPU accelerated PhysX effects. PCGamesHardware.com had the chance to talk with Oles Shishkovtsov, Chief Technology Officer at 4A Games, about improvements that are planned for PC version of the game.
Update: Metro Last Light – GPU PhysX effects explored
PC Games Hardware: You keep the support for GPU PhysX in Metro Last Light. If so can we expect some improvements or enhancements compared to Metro 2033 (e.g. soft bodies, debris, and destructible environments)? What graphics card do you recommend for maxed details in Full HD with Antialiasing? An upcoming Nvidia Kepler-based Geforce for example?
Oles Shishkovtsov: Yes, you can expect a lot of improvements, especially in destruction and debris. The upcoming Geforce cards will be fully supported.
PC Games Hardware: When benchmarking Metro 2033 we found out that the engine utilized more than four cores of multicore CPUs if we were using the advanced PhysX effects on CPU, so you are utilizing Nvidias PhysX SDK 3.x? Will all the advanced PhysX effects only be available in PC version?
Oles Shishkovtsov: That’s the common misconception that PhysX 2.X cannot be multithreaded. Actually it is internally designed to be multithreaded! The only thing – it takes some programmer time to enable that multi-threading (actually task generation), mostly to integrate with engine task-model and ensure proper load-balancing. So, 2033 used PhysX 2.8.3, and Last Light uses similar, a slightly modified version at the time of writing. And yes, advanced PhysX effects will be available only on PC.
However, we are hoping that this time Metro will be able to surprise us with more than two minor particle effects (as in Metro 2033 – while “debris, smoke and dust” were promised) and it won’t require “upcoming GeForce card” to run those GPU PhysX effects with playble framerate.
Almost four years has passed since NVIDIA aquired Ageia and presented their version of hardware accelerated PhysX Technology. However, anyone who is watching GPU PhysX progress closely can say, that so far it has not shown any significant advancement – but is the fight already lost or is it just taking time to harness up, but will ride fast?
We got a chance to chat with Tony Tamasi, Senior Vice President of Content & Technology in NVIDIA, Ashu Rege, Vice President of Content & Technology, and Rev Lebaredian, Director of Engineering, to clear up these questions, and recieve some insider information on future development plans for PhysX SDK and NVIDIA APEX toolset.
PhysXInfo.com: Over last years, amount of GPU PhysX games is actually decreasing. There were five games in 2009, three in 2010 and so far only one in 2011. How can you explain that?
Tony Tamasi: It was a choice on our part. We had a large amount of resources we could otherwise dedicate to content, but we needed to advance the core technology. We needed to get PhysX 3 done, and we needed to get APEX done to the degree where it is usable by game developers. We had to put a lot of resources there, which meant that some of those resources weren’t directly working on games.
But in the long term, game developers can actually use PhysX and APEX, and make use of the GPU without significant amounts of effort, so that a year or two years from now more games will come out using GPU physics.
Rev Lebaredian: When we initially acquired Ageia, we made a big effort to move many games over to GPU PhysX. We learned a lot in that period of time: getting GPU physics into games, what are the problems, what works and what doesn’t. That gave us the opportunity to regroup, refocus, and figure out how to do it correctly.
We made a conscious decision. After we did a bunch of PhysX and APEX games in 2009 and early 2010, we said “Ok, we have learned enough, we need to sit down and focus on finishing APEX and changing it based on what we just learned, as well as PhysX 3”. Doing as many titles as we were doing before was just going to slow us down.
It made more sense to slow down the content pipeline but get the tools right, but that puts us in the position when once those are complete, it is actually less work for us to get PhysX in games.
This slowdown has not been because of any problems. It is something that we have decided to do.
Another interesting research paper was published by Dr. Matthias Müller-Fischer, PhysX SDK Research Lead in NVIDIA.
It is called Adding Physics to Animated Characters with Oriented Particles and it further expands oriented particles approach with techniques for simulation of clothing on animated characters.
We present a method to enhance the realism of animated characters by adding physically based secondary motion to deformable parts such as cloth, skin or hair. To this end, we extend the oriented particles approach to incorporate animation information. In addition, we introduce techniques to increase the stability of the original method in order to make it suitable for the fast and sudden motions that typically occur in computer games. We also propose a method for the semi-automatic creation of particle representations from arbitrary visual meshes. This way, our technique allows us to simulate complex geometry such as hair, thick cloth with ornaments and multi-layered clothing, all interacting with each other and the animated character.
NVIDIA has published a technical article, related to Smoothed Particle Hydrodynamics (SPH) fluid simulation method, used in as part of GPU PhysX effects in recently released Alice: Madness Return title.
As we said before, overall level of PhysX particle effects is impressive, but fluid dynamics itself can only be called – decent. We already saw more detailed SPH-fluids in Cryostasis (up to 30 000 particles), gameplay affecting fluids in Crazy Machines 2 and even SPH based smoke in Batman: Arkham Asylum and Mafia II.
However, if you are interested in SPH-fluid simulation technique and particles rendering, we recommend you to familiarize with following materials (in addition to the article this post is related to – which is an interesting read anyway):