Archive for September, 2010
Interesting paper, called “Scalable Fluid Simulation using Anisotropic Turbulence Particles” has appeared at homepage of Dr. Markuss Gross, from ETH Zurich.
As far as we know, same solver is used in APEX Turbulence module.
It is usually difficult to resolve the fine details of turbulent flows, especially when targeting real-time applications. We present a novel, scalable turbulence method that uses a realistic energy model and an efficient particle representation that allows for the accurate and robust simulation of small-scale detail. We compute transport of turbulent energy using a complete two-equation k–e model with accurate production terms that allows us to capture anisotropic turbulence effects, which integrate smoothly into the base flow. We only require a very low grid resolution to resolve the underlying base flow.
As we offload complexity from the fluid solver to the particle system, we can control the detail of the simulation easily by adjusting the number of particles, without changing the large scale behavior. In addition, no computations are wasted on areas that are not visible. We demonstrate that due to the design of our algorithm it is highly suitable for massively parallel architectures, and is able to generate detailed turbulent
In addition, this paper comes with nice video demonstration (92 mb). It is worth to watch.
Thanks to AquaGeneral for the link.
Now, when Subscription Advantage Pack for 3ds Max 2011 and 3ds Max Design 2011 was released, we can verify that it includes updated version of PhysX plug-in, designated as 2.40.0808.2140, avaialble in 32- and 64-bit variants and based on PhysX SDK 22.214.171.124.
Update: How to achieve quality simulation with PhysX plug-in for 3ds Max
Update #2: New PhysX plug-n v. 2.60 released
Unfortunately, APEX Clothing tools are in not included in this version of the plug-in.
Note: To use this plug-in with RayFire Tool, you need to update RayFire to version 1.51.02
For those of you, who still can’t decide if new PhysX plug-in is worth the update, here are full Release Notes we took from documentation:
Issues Fixed (Present in Previous Releases)
- [#5023] Rotating collision shape on biped does not maintain position in space
- [#4936] Resetting a project does not reset PhysX global settings
- [#5022] Capsule’s shape is altered incorrectly when height or radius is modified
- [#5061] Loading a project from 2010 with constraint fails to load in Max2011
- [#5098] Constraint Swing Y and Swing Z reversed in UI
New Known Issues
- [#5107] Baking rigid bodies attached to constraints yields incorrect results
- [#5152] Baking to keyframes offsets values when Start Frame is not 0
- [#5153] Initial Spin speed not in degrees per second
Apart from other substantial features and changes, like Deferred Render, Beast Lighmapping technology, Umbra Occlusion Culling and Unified Editor, Unity 3.0 also includes updated physics engine, based on recent version of PhysX SDK.
- Upgraded PhysX to 2.8.3.
- Cloth and clothing simulation: use the new InteractiveCloth, SkinnedCloth and ClothRenderer components.
New in Unity 3 are two kinds of cloth: Fully physically simulated cloth effects that interact fully with the rest of the environment. The other, Skinned Cloth, is an optimized solution for garments on animated characters.
You can use it for animated shirts, trousers, skirts, capes and hair in a physically accurate way. It is highly optimized and can handle high poly animated cloth pieces.
- Layer based ignore collisions: use the Physics inspector or Physics.IgnoreCollision().
- Continuous collision detection, to make sure that fast moving colliders will not pass through other colliders. See Collider.collisionDetectionMode.
- Added Physics.SphereCast() and Physics.CapsuleCast() to implement volume raycasts.
- Added Rigidbody.SweepTest() to check if a Rigidbody would collide with anything if moved into a certain direction.
You can check most of Unity 3.0 features by yourself directly from your browser, using newest Unity Bootcamp Demo (unity webplayer is required).
This month’s build of UDK features significant additions, including:
· UDK users now have access to the gameplay profiler tool.
· Matinee’s movement tracks can now be split into individual translation and rotation components.
· Users can bulk edit texture properties within the Content Browser.
Apart from other usefull changes, September UDK is upgrading PhysX SDK integration with newest features of 2.8.4 SDK, like driverless destribution, SSE2 optimizations and enhanced cloth solver.
Also, we have noticed full pack of NVIDIA APEX .dlls – when APEX will be released to public, you’ll be able to use it with UDK right away.
· ‘PhysXDestructible’ has been removed.
· APEX destructibles are replacing them.
As for APEX Toolset release (without it APEX integration into UDK is useless for regular developer), several sources are indicating that this is going to happen somewhere in October
As good tradition, several interesting physical demos were presented during GTC Day 1 Keynote by Tony Tamasi, Senior Vice President Content and Technology in NVIDIA.
First one was showing some high-fidelity smoke simulation, with particles interacting fully with characters, producing nice fluid and turbulent behaviour.
Version 1.2.2 – 2010-09-20
! Change: new post processing (post-FX) effect.
! Change: scores submissions are limited to fullscreen mode + No AA + No PostFX.
! Update: compiled with PhysX SDK 126.96.36.199.
* Bugfix: the resolution 1920×1080 was not saved at the closing of FluidMark.
As you may notice, particles have changed their color from vibrant yellow to bloody red, but major improvements are related to usage of newest PhysX SDK 188.8.131.52.
According to Golem.de upcoming 3DMark 2011 benchmark won’t rely on PhysX integration, but use some in-house physics engine, based on DX 11 Compute Shaders.
From our opinion, this is natural change – solution, that brings substantial benefits to one of the GPU manufacturers, can hardly fit into unbiased benchmark, which 3DMark claims to be.
NVIDIA Physx Review Part 2 by TecnoGaming
This video, showcasing GPU PhysX usage in several games like Warmonger, Cryostasis and Mafia II, is supplementing “NVIDIA PhysX” article from TecnoGaming.com
PhysX Teapot Dryer by Phrogz42
Another PhysX plug-in 2.06 for 3ds Max demonstration, this time – rigid body simulation with 1331 teapots in a clothing dryer, each teapot is a simple convex hull with 16 vertices.
First part of the entry is dedicated to brief overview of PhysX vs AMD’s physics solutions topic, similar to our “AMD and PhysX: History of the Problem” article, and can be read briefly.
But second part is focused on recent PhysX and x87 theme, and original “PhysX87: Software Deficiency” article by David Kanter. Original statement of mr. Kanter sounds like “SSE can easily run 1.3-2X faster than similar x87 code“, and that’s where Scali gives him a full pack of criticism:
Kanter then makes claims about the gains that can be had from converting the code to SSE. He claims that SSE could quadruple performance in theory, and in reality a boost of more than 2x would be possible. Kanter claims that a modern optimizing compiler can easily vectorize the code for SSE automatically, and such gains could be had from just a recompile.
So nVidia is just leaving all this performance on the table. What’s more, if PhysX would indeed be 2-4 times faster on CPU, it would actually be a threat to GPU-accelerated physics. Kanter claims that PhysX is hobbled on the CPU, and that nVidia is deliberately doing this to make GPU physics look good.
In synthetic tests, there is about 8% to be gained from recompiling. This is nowhere near the 2-4x figure that Kanter was using. In fact, 8% faster PhysX processing would mean even less than 8% higher framerates in games, since PhysX is not the only CPU-intensive task in a game.
Perhaps the net gain in framerate would be closer to 3-4%, depending on the game. In other words, recompiling PhysX with SSE would not make CPUs threaten GPU physics. Not even close. The difference would be lost in the margin of error, most likely.
but in spite of this
Kanter’s article, wrong as it may be, is linked on many news sites and forums all over the web, and many discussions ensue. Most people buy into Kanter’s article, and some sites make even more bold claims than Kanter himself, referring to Kanter’s article as ‘absolute proof’ of nVidia’s evil actions. This is exactly what AMD needs.
You may found Scali’s article biased (AMD conspiracy theory and stuff), but it is worth a read as it has common sense. Give it a glimpse, and share your thoughts.
Time to expand auditory a little – as we are adding Russian branch of PhysX News section. From now on you can easily switch between languages using this small panel:
I, fellow Zogrim, gonna be responcible for Russian version as well.