Monthly Archives: July 2010

Live Real-Time Demos at SIGGRAPH

So one problem with SIGGRAPH is that you hear about the cool thing that you missed and didn’t even know about until it was too late. Here’s one that’s getting repeated: the Computer Animation Festival’s Live Real-Time Demos session. Hall B, 4:30-5:15 pm Tuesday and Wednesday; I just caught the tail-end of Monday’s show and it was worth seeing, so I’ll go back for the rest tomorrow.

What else didn’t you miss yet? Hmmm, in Emerging Technologies Sony’s 360-degree autostereoscopic display is cute, I’ve heard the 3D multitouch table is very worthwhile, and you must try out the Meta Cookie (have someone take your picture while you’re in the headgear, it’s something your grandchildren will want to see). I was also interested to see QuintPixel from Sharp, as it justified their earlier Quattron “four primary colors” display.

More later – Mental Images reception time.

Fleet-Footed Faster Forward

The Fast Forward event at SIGGRAPH is set of very short presentations Sunday evening that runs through all the papers at SIGGRAPH. Lately SIGGRAPH has become a “big tent”, including a wide range of fields. This year there are, by my count, 133 SIGGRAPH papers, giving say 50 seconds to each presentation in the two-hour period. This is a pleasant-enough way to cull through all the papers and find which ones to see, and there is the occasional witty presentation, but to be honest, I’m a bit worn out on the method – too slow! In the past few years I find myself looking at my watch halfway through and thinking “egads, still another hour?” and my monocle pops from my eye with comic effect.

So I liked seeing that CGW is hosting a 3 minute 44 second video summary of some of the SIGGRAPH papers. Only 23 papers summarized, but I love that each gets just a sentence – you’re in, you’re out, and you have some sense if it’s a paper you need to see. I wish I had this for all the papers. Second in awesomeness would be a single web page that lists all the abstracts together, for a quick skim. I should write a Perl script that makes one from ACM’s SIGGRAPH 2010 TOC. Also at CGW’s site is a 2 minute 41 second (plus long credits) video summary of the Emerging Technologies area, purely visual – nice, it gives me a little taste, prepping my senses for what I will see there and want to learn more about.

Two and a Half Books

I’ve learnt of two new books in the past few weeks, worth mentioning as books to check out at SIGGRAPH (or using Amazon’s “Look Inside”, of course):

iPhone 3D Programming: Developing Graphical Applications with OpenGL ES, by Philip Rideout, O’Reilly Press. A better title might have been “Programming OpenGL ES on the iPhone”, as it focuses on OpenGL ES more than on the iPhone per se. Which is fine; there are already lots of iPhone programming books, and almost none that are focused more on OpenGL ES itself (the only other OpenGL ES 2.0 book I know of is this one). The book is C++ oriented, with some Objective C as needed for glue. From my brief skim, this looks like a well-illustrated, readable guide that hits many different effects: reflection maps, skinning, antialiasing, etc. That said, I haven’t yet had the opportunity to program on any mobile devices, so can’t give an expert review. When I do give it a try, this looks like the book I’ll read first.

Update: A draft of this book is free on the web, see it here. It looks to be essentially the same as the published work (but with some hand-drawn figures), and is nicer in some ways, as the pages allow color images (always good for a graphics book).

Light & Skin Interactions: Simulations for Computer Graphics Applications, by Gladimir V. G. Baranoski and Aravind Krishnaswamy, Morgan-Kaufmann Press. This one’s out of my league as a casual skim. Paging through and seeing “the eumelanin absorption coefficient is given by…” and “Scattering in either the stratum corneum or epidermis…” shows me how little I know of the world in general. Anyway, interesting to see a whole book about this critical type of material. Searching through it, there’s minimal coverage of, for example, d’Eon and Luebke’s work, so I can’t say it has much direct application to interactive computer graphics at this point.

That’s all for the real books…

The half a book (at best): Game GPU Graphics Gems: Real-Time Rendering The Redux (aka GGGG:RTRTR), by anyone who wants to edit it. When I “edited” the quasi-book Another Introduction to Ray Tracing a few months ago, I thought back then that I’d start another book for SIGGRAPH. Like the first stunning collection, this was an hour of work gathering Wikipedia articles (hardest part was choosing a cover). There are plenty more articles to gather about interactive rendering, and you’re most welcome to add any good ones you find to this book, make your own, etc. – it’s a wiki page, after all. More seriously, I like having a single, tight page of links to Wikipedia articles about interactive rendering, vs. wandering around and haphazardly seeing what’s there.

GPU Ray Tracing BOF at SIGGRAPH 2010

There will be a Birds of a Feather gathering at SIGGRAPH 2010 about GPU Ray Tracing: Wednesday, 4:30-6 pm, Room 301 A.

A brief description from Austin Robison: We won’t have a projector or desktop machines set up, but please feel free to bring your laptops to show off what you’ve been working on! Additionally, I’ve created a Google Group mailing list that I hope we can use, as a community, to share insights and ask questions about ray tracing on GPUs not tied to any specific API or vendor. Please sign up and share your news, experiences and ideas: http://groups.google.com/group/gpu-ray-tracing.

I3D 2011

The website for I3D 2011 is now up, including the time/place and CFP. I3D will be in San Francisco next year, from February 18-20th. I3D probably has a higher percentage of graphics papers relevant to games than any other conference; this year five of the papers described techniques already in use in games (including high-profile titles like Batman: Arkham Asylum and Civilization 5), and many of the other papers were also highly relevant. Unfortunately, very few game developers attend; I hope next year’s location (San Francisco is home to a large number of developers) will help.

I3D is a great small conference to publish real-time rendering papers. One advantage it has for authors over Eurographics conferences like EGSR, and co-sponsored conferences like HPG and SCA (in “Europe” years) is that it is not subject to Eurographics’ monumentally stupid “authors can’t post copies of their papers for a year after the conference” policy. This policy, of course, hurts the chance of your paper being cited by making it harder for people to read it – brilliant! Hopefully EG will see the error of its ways soon – until then, you are better off sending your papers to non-EG conferences like I3D.

SIGGRAPH 2010 Game Content Roundup

With less than two weeks until the conference, here’s my final pre-SIGGRAPH roundup of all the game development and real-time rendering content. This is to either to help convince people who are still on the fence about attending (unlikely at this late date) or to help people who are trying to decide which sessions to go to (more likely). If you won’t be able to attend SIGGRAPH this year, this might at least help you figure out which slides, videos, and papers to hunt for after the conference.

First of all, the SIGGRAPH online scheduler is invaluable for helping to sort out all the overlapping sessions (even if you just “download” the results into Eric’s lower-tech version). The iPhone app may show up before the conference, but given the vagaries of iTunes app store approval, I wouldn’t hold my breath.

The second resource is the Games Focus page, which summarizes the relevant content for game developers in one handy place. It makes a good starting point for building your schedule; the rest of this post goes into additional detail.

My previous posts about the panels and the talks, and several posts about the courses go into more detail on the content available in these programs.

Exhibitor Tech Talks are sponsored talks by various vendors, and are often quite good. Although the Games Focus page links to the Exhibitor Tech Talk page, for some reason that page has is no information about the AMD and NVIDIA tech talks (the Intel talk on Inspecting Complex Graphics Scenes in a Direct X Pipeline, about their Graphics Performance Analyzer tool, could be interesting). NVIDIA does have all the details on their tech talks at their SIGGRAPH 2010 page; the ones on OpenGL 4.0 for 2010, Parallel Nsight: GPU Computing and Graphics Development in Visual Studio, and Rapid GPU Ray Tracing Development with NVIDIA OptiX look particularly relevant. AMD has no such information available anywhere: FAIL.

One program not mentioned in the Games Focus page is a new one for this year: SIGGRAPH Dailies! where artists show a specific piece of artwork (animation, cutscene sequence, model, lighting setup, etc.) and discuss it for two minutes. This is a great program, giving artists a unique place to showcase the many bits of excellence that go into any good film or game. Although no game pieces got in this year, the show order includes great work from films such as Toy Story 3, Tangled, Percy Jackson, A Christmas Carol, The Princess and The Frog, Ratatouille, and Up. The show is repeated on Tuesday and Wednesday overlapping the Electronic Theater (which also should not be missed; note that it is shown on Monday evening as well).

One of my favorite things about SIGGRAPH is the opportunity for film and game people to talk to each other. As the Game-Film Synergy Chair, my primary responsibility was to promote content of interest to both. This year there are four such courses (two of which I am organizing and speaking in myself): Global Illumination Across Industries, Color Enhancement and Rendering in Film and Game Production, Physically Based Shading Models in Film and Game Production, and Beyond Programmable Shading I & II.

Besides the content specifically designed to appeal to both industries, a lot of the “pure film” content is also interesting to game developers. The Games Focus page describes one example (the precomputed SH occlusion used in Avatar), and hints at a lot more. But which?

My picks for “film production content most likely to be relevant to game developers”: the course Importance Sampling for Production Rendering, the talk sessions Avatar in Depth, Rendering Intangibles, All About Avatar, and Pipelines and Asset Management, the CAF production sessions Alice in Wonderland: Down the Rabbit Hole, Animation Blockbuster Breakdown, Iron Man 2: Bringing in the “Big Gun”, Making “Avatar”, The Making of TRON: LEGACY, and The Visual Style of How To Train Your Dragon, and the technical papers PantaRay: Fast Ray-Traced Occlusion Caching, An Artist-Friendly Hair Shading System, and Smoothed Local Histogram Filters. (unlike much of the other film production content, paper presentation videos are always recorded, so if a paper presentation conflicts with something else you can safely skip it).

Interesting, but more forward-looking film production stuff (volumetric effects and simulations that aren’t feasible for games now but might be in future): the course Volumetric Methods in Visual Effects, the talk sessions Elemental Training 101, Volumes and Precipitation, Simulation in Production, and Blowing $h!t Up, and the CAF production session The Last Airbender: Harnessing the Elements: Earth, Air, Water, and Fire.

Speaking of forward-looking content, SIGGRAPH papers written by academics (as opposed to film professionals) tend to fall in this category (in the best case; many of them are dead ends). I haven’t had time to look at the huge list of research papers in detail; I highly recommend attending the Technical Papers Fast-Forward to see which papers are worth paying closer attention to (it’s also pretty entertaining).

Some other random SIGGRAPH bits:

  • Posters are of very mixed quality (they have the lowest acceptance bar of any SIGGRAPH content) but quickly skimming them doesn’t take much time, and there is sometimes good stuff there. During lunchtime on Tuesday and Wednesday, the poster authors are available to discuss their work, so if you see anything interesting you might want to come back then and ask some questions.
  • The Studio includes several workshops and presentations of interest, particularly for artists.
  • The Research Challenge has an interesting interactive haunted house concept (Virtual Flashlight for Real-Time Scene Illumination and Discovery) presented by the Square Enix Research and Development Division.
  • The Geek Bar is a good place to relax and watch streaming video of the various SIGGRAPH programs.
  • The SIGGRAPH Reception, the Chapters Party, and various other social events throughout the week are great opportunities to meet, network, and talk graphics with lots of interesting and talented people from outside your regular circle of colleagues.

I will conclude with the list of game studios presenting at SIGGRAPH this year: Activision Studio Central, Avalanche Software, Bizarre Creations, Black Rock Studio, Bungie, Crytek, DICE, Disney Interactive Research, EDEN GAMES, Fantasy Lab, Gearbox, LucasArts, Naughty Dog, Quel Solaar, tri-Ace, SCE Santa Monica Studio, Square Enix R&D, Uber Entertainment, Ubisoft Montreal, United Front Games, Valve, and Volition. I hope for an even longer list in 2011!

Another SIGGRAPH Scheduler

SIGGRAPH 2009 scheduleI’ve messed around with various scheduling methods over the years for SIGGRAPH, but find I dislike the form factor of PDA-like devices: you can see a few hours, or maybe a day’s activities at best. Taking notes can be tiresome, you need lots of clicks needed to find stuff, and sometimes the battery dies.

So for the past few years I’ve locked onto classic graphite stick & cellulose technology. Honestly, I like it a lot: folds up and fits in my pocket, it’s easy to see conflicts among events, I can instantly figure out when I’m free, and lots of room on the back for notes and whatnot. At the end of the conference I automatically have a hardcopy, no printing necessary. I mention it here as an honestly useful option, as this low-tech approach works for me. The main drawback is that you look like a nerd to other nerds. Hey, I like my iPod Touch, I’ll put the SIGGRAPH Advanced Program on it with Discover, but the sheet o’ paper will be my high-level quick & dirty way to navigate and write down information. It’s sort of how I like RememberTheMilk for reminders more than Google Calendar: I can enter data very simply, without time wasted navigating the UI. Now if only the sheet of paper would automatically unfold when I take it out of my pocket, I could increase efficiency by 0.43 seconds.

Random graphics paper title generator

Try it – it’s a blast (keep hitting “refresh” to see new titles). Here’s a few that I got:

  • Bidirectional Rendering of Caustics for Light Fields
  • Reflective Normal-mapped Light Fields
  • Rendering of Inverse Geometry
  • Texturing of Multi-resolution Geometry using Polygonal Approximation
  • Displacement Mapping of Reflective Geometry for Surfaces

Can’t tell them from the real paper titles…

More SIGGRAPH Course Updates

After my last SIGGRAPH post, I spent a little more time digging around in the SIGGRAPH online scheduler, and found some more interesting details:

Global Illumination Across Industries

This is another film-game crossover course. It starts with a 15-minute introduction to global illumination by Jaroslav Křivánek, a leading researcher in efficient GI algorithms. It continues with six 25-30 minutes talks:

  • Ray Tracing Solution for Film Production Rendering, by Marcos Fajardo, Solid Angle. Marcos created the Arnold raytracer which was adopted by Sony Pictures Imageworks for all of their production rendering (including CG animation features like Cloudy with a Chance of Meatballs and VFX for films like 2012 and Alice in Wonderland). This is unusual in film production; most VFX and animation houses  use rasterization renderers like Renderman.
  • Point-Based Global Illumination for Film Production, by Per Christensen, Pixar. Per won a Sci-Tech Oscar for this technique, which is widely used in film production.
  • Ray Tracing vs. Point-Based GI for Animated Films, by Eric Tabellion, PDI/Dreamworks. Eric worked on the global illumination (GI) solution which Dreamworks used in Shrek 2; it will be interesting to hear what he has to say on the differences between the two leading film production GI techniques.
  • Adding Real-Time Point-based GI to a Video Game, Michael Bunnell, Fantasy Lab. Mike was also awarded the Oscar for the point-based technique (Christophe Hery was the third winner). He actually originated it as a real-time technique while working at NVIDIA; while Per and Christophe developed it for film rendering, Mike founded Fantasy Lab to further develop the technique for use in games.
  • Pre-computing Lighting in Games, David Larsson, Illuminate Labs. Illuminate Labs make very good prelighting tools for games; I used their Turtle plugin for Maya when working on God of War III and was impressed with its speed, quality and robustness.
  • Dynamic Global Illumination for Games: From Idea to Production, Anton Kaplanyan, Crytek. Anton developed the cascaded light propagation volume technique used in CryEngine 3 for dynamic GI; the I3D 2010 paper describing the technique can be found on Crytek’s publication page.

The course concludes with a 5 minute Q&A session with all speakers.

An Introduction to 3D Spatial Interaction With Videogame Motion Controllers

This course is presented by Joseph LaViola (director of the University of Central Florida Interactive Systems and User Experience Lab) and Richard Marks from Sony Computer Entertainment (principal inventor of the Eyetoy, Playstation Eye, and Playstation Move). Richard Marks gives two 45-minute talks, one on 3D Interfaces With 2D and 3D Cameras and one on 3D Spatial Interaction with the PlayStation Move. Prof. LaViola discusses Common Tasks in 3D User Interfaces, Working With the Nintendo Wiimote, and 3D Gesture Recognition Techniques.

Recent Advances in Real-Time Collision and Proximity Computations for Games and Simulations

After an introduction to the topic of collision detection and proximity queries, this course goes over recent research in collision detection for games including articulated, deformable and fracturing models. It concludes with optimization-oriented talks such as GPU-Based Proximity Computations (presented by Dinesh Manocha, University of North Carolina at Chapel Hill, one of the most prominent researchers in the area of collision detection), Optimizing Proximity Queries for CPU, SPU and GPU (presented by Erwin Coumans, Sony Computer Entertainment US R&D, primary author of the Bullet physics library, which is widely used for both games and feature films), and PhysX and Proximity Queries (presented by Richard Tonge, NVIDIA, one of the architects of the AGEIA  physics processing unit – the company was bought by NVIDIA and their software library formed the basis of the GPU-accelerated PhysX library).

Advanced Techniques in Real-Time Hair Rendering and Simulation

This course is presented by Cem Yuksel (Texas A&M University) and Sarah Tariq (NVIDIA). Between them, they have done a lot of the recent research on efficient rendering and simulation of hair. The course covers all aspects of real-time hair rendering: data management, the rendering pipeline, transparency, antialiasing, shading, shadows, and multiple scattering. It concludes with a discussion of real-time dynamic simulation of hair.

Ray Tracing Solution for Film Production Rendering
Fajardo

2:40 pm
Point-Based Global Illumination for Film Production
Christensen

3:05 pm
Ray Tracing vs. Point-Based GI for Animated Films
Tabellion

3:30 pm
Break 

3:45 pm
Adding Real-Time Point-based GI to a Video Game
Bunnell

4:15 pm
Pre-computing Lighting in Games
Larsson

4:45 pm
Dynamic Global Illumination for Games: From Idea to Production Kaplanyan

5:10 pm
Conclusions, Q & A
Ray Tracing Solution for Film Production Rendering

Fajardo

2:40 pm

Point-Based Global Illumination for Film Production

Christensen

3:05 pm

Ray Tracing vs. Point-Based GI for Animated Films

Tabellion

3:30 pm

Break

3:45 pm

Adding Real-Time Point-based GI to a Video Game

Bunnell

4:15 pm

Pre-computing Lighting in Games

Larsson

4:45 pm

Dynamic Global Illumination for Games: From Idea to Production Kaplanyan

5:10 pm

Conclusions, Q & A

All

All