Archive for the ‘Chromium’ Category

Two Methods for driving OpenGL Display Walls

7. July 2008

Recently the the VMML at the University of Z√ľrich performed a benchmark comparing Chromium and Equalizer on a display wall. The result surprised me, as I would have expected less difference between the two solutions in this setup, since only static display lists are used. Unfortunately neither InfiniBand nor the broadcast SPU were available for this test, which should improve the Chromium performance.

The performance graph is on the left. You can download the White Paper from the Equalizer website.


Parallel Rendering Timeline

16. May 2008

Parallel Rendering Timeline
On the right there’s a simple timeline of the most important toolkits for parallel rendering, naturally with more details for Equalizer.
I plan to extend this over time, and maybe even creating one with the major hardware milestones.
Any input is welcome – Skywriter VGXT, anyone? ūüėČ

Chromium vs Equalizer

29. July 2007

Often I am getting into discussions between the differences and the overlap between Chromium and Equalizer. Just recently I had an email conversation with one of the Chromium contributers about the comparison on the Equalizer website. The point of this post is to get your feedback and input to make this page easier to understand and more balanced.

Admittedly, the page simplified things quite a bit. I tried to keep things simple in order to make the main differences clear. On the other hand, this was unfair for Chromium, since it failed to mention it’s parallel programming aspect. I have updated the page already, but now it is no longer simple.

My opinion is that most of the time Chromium is used and perceived as a tool to run unmodified application in a one-to-may display wall configuration. The parallel extensions (composition and OpenGL synchronization) are helpful when developing parallel applications, but don’t go far enough.

Personally I think that Equalizer addresses more of the common problems for parallel OpenGL applications (configuration, synchronization, network distribution) and is the better tool for developing a parallel application. On the other hand, Chromium is an excellent tool to run unmodified OpenGL applications on large-scale display walls, as demonstrated at WWDC’07.

So – what do you think and what would you change on the comparison page? Are there other arguments you see for Chromium or Equalizer? Please leave a comment and I’ll reply.

MacResearch WWDC Article

17. July 2007

MacResearch is running a nice interview with me about the WWDC event.

WWDC setup

25. June 2007

Since gWHIZ asked so nicely, here is a quick summery of the WWDC setup (list price as of today):

  • ¬†9 MacPro, ATI x1900 XT, 4 GB, 2×2 2.66GHz: $31.023
  • 19 30-inch Cinema Display: $34.181
  • 18 Vesa Mounts: $522
  • Gigabit Switch and Cabling: ¬†I don’t know what was used, but it’s cheap nowadays
  • Custom-built plywood wall: priceless!

The networking was probably the weakest link in the setup. All machines were on the same network. Optimisation is possible by putting the machines into two networks, both connected to the same frontend machine. Another optimisation can be implemented in Chromium by having a binary tree to submit the GL command stream.

Some money can be saved on the render nodes, since I don’t believe all the RAM is needed. Likewise, profiling might show that slower processors are sufficient.¬†

Back from WWDC

18. June 2007

Amira running through Chromium on the WWDC07 Display Wall

Yesterday I got back from WWDC – what a week! In addition to the prepared demo of Google Earth, Amira and VMD, we have managed to get two additional applications to run on the display wall through Chromium: LigandScout (molecular modeling) and SOAP (GPS satellite analysis).

The display wall was gorgeous, and even bigger than expected. We had a total of 18 30-inch Cinema Displays, arranged in a 6×3 layout. The other hardware was also standard Apple hardware you’ll get at the store: nine MacPro’s with a ATI x1900 graphics card, gigabit ethernet and one MacPro as the master to run the applications.

Google Earth running through Chromium on the WWDC07 Display Wall

People walking by were stunned by the size of the wall, and all applications looked fantastic and showed a variety of use cases. Often people lost a sense of scale and assumed we use 23-inch displays ūüėČ

In the afternoons I’ve had some time to attend the conference, and heard quite a few interesting talks.

Drop me a note or a comment if you’ld like to see a specific application picture.

WWDC, here I come…

7. June 2007

The new Equalizer polygon renderer

The last couple of days I have been busy preparing the WWDC demo of Chromium and Equalizer. We’ve made excellent progress, and certified quite a few applications (Google Earth, VMD, Paraview and Amira) to run on the display wall using Chromium.

On the Equalizer side, there is a new, improved version of the polygonal renderer using a much better internal data structure (a 3D kd-tree) and per-vertex normals. I haven’t been able to test it thouroughly, but I’ll have some time before the show to try it out on the MacPro cluster.

Tomorrow I’ll be travelling to San Francisco, and I am looking forward to an exciting show and to see you all! The scheduled times for the demos are Tue-Fri, 9am-12am.

One more demo app: VMD

1. June 2007

VMD, Chromium and Mac OS X

Things are moving well now – VMD is working as well for the WWDC display wall demonstration. This covers a little bit the whole scientific visualization angle. Performance is really good if you enable ‘cached rendering’ (display lists?) in VMD.

Google Earth, Chromium and Mac OS X

31. May 2007

Google Earth, Chromium and Mac OS X

Finally a cool application for demonstrating Chromium on OS X: Google Earth! After some fixing of the CGL/AGL Chromium code, customizing the config file, removing all whitespace from the path and other minor issues I could get it running on my mini display wall I use for testing the WWDC07 setup.

Chromium for sure is bandwidth-hungry. My MacBook Pro pumps out about 50MB/s (bytes, not bits) to the two MacPro’s – thankfully the broadcast SPU works.

I can’t wait to see it on the big wall!

Next Stop: WWDC07

23. May 2007

Apple will be demoing a display wall made out of 5×3 30-inch cinema displays at WWDC07 – that’s 3.4×1.6m (136×63.9 inch) or in other words: a 150-inch display with a 60 MPixel resolution!

And what is even better – I will be there with a colleague from TG to show Chromium and Equalizer, talk to the developers and get the Mac people excited about parallel rendering.

It will be quite a nice setup to play with. The only thing I am concerned with is that each MacPro drives two displays from a single GPU – 8 MPixels needs quite some fill rate. ūüôā