Tag Archives: history

One that fooled me

In my post about Ken Torrance I mentioned seeing in 1984 a synthesized image that looked real. The soft shading of radiosity was a new look, not at all like the sharp-edged shadows and reflections seen with classical ray tracing. Cindy Goral kindly scanned in the images from her thesis (they’re also reprinted in Cohen and Wallace’s book on radiosity and Roy Hall’s book on illumination and color), as I wanted to put them up, for old-time’s sake.

The object is a sculpture by John Ferren, made in 1968, entitled Construction in Wood, a Daylight Experiment. I was happy to find this sculpture is still sometimes rotated into display at the Hirshhorn in Washington, DC, where Cindy saw it back around 1984. To quote this page, from 2007: “It is set up in front of an unshaded window, so that sunlight reflects the fluorescent paint on the back sides of the wood slats onto the white paint on the front sides, tricking your eye into imagining that the light comes from fluorescent bulbs.” Also, through the miracle of Google, Cohen and Wallace’s description of the sculpture is easily accessible; see that page for an overhead view. No Google Image or Flickr of it, though, that I could find.

What’s most interesting about this sculpture from a CG standpoint is how it was practically designed as a worst-case for ray tracing and best-case for radiosity. All the surfaces facing the viewer are white, so it is only through indirect diffuse-diffuse interreflection, a.k.a. color bleeding, that you see any color. A classical ray trace comes out black, as no light directly illuminates any of the surfaces. Here’s a modern-day version with Maya, at the bottom of the page (update: shucks, dead link and archive.org doesn’t have it. But, there’s a SketchUp model here to download, and a free SKP importer for Blender).

The sculpture, simulation:

and reality (photo by Jerry Scharf):

Bits of News

Just some quick bits to chew on for breakfast:

  • Microsoft announced Project Natal at E3; the (simulated) video is entertaining. Lionhead Studios’ demo is also worth a look. Somehow a little creepy, and I suspect in practice there’s a high likelihood that a user will quickly run off the rails and not do what’s expected, but still. Considering how limited the Eye Toy is compared to its hype, I’m not holding my breath, but it’s interesting to know & think about. (thanks to Adam Felt for the link)
  • New book out, Graphics Shaders: Theory and Practice. It’s about GLSL, you can find the Table of Contents and other front matter at the book’s site (look to the right side). I hope to get a copy and give a review at some point.
  • I mentioned Mark Haigh-Hutchinson’s Real-Time Cameras book in an earlier post. The, honestly, touching story of its history is republished on Mark DeLoura’s blog at Gamasutra.
  • Nice history of graphics cards, with many pictures.
  • Humus describes a clever particle rendering optimization technique (update), and provides a utility. Basically, make the polygon fit the visible part of the particle to save on fill rate. One of those ideas that I suspect many of us have wondered if it’s worth doing. It is, and it’s great to have someone actually test it out and publish the results.
  • This is an interesting concept: with an NVIDIA card and their new driver you can now turn on ambient occlusion for 22 games that don’t actually use this technique in their shipped shaders. In itself, this feature is a minor plus, but brings up all sorts of questions, such as buying into a particular brand to improve quality, who controls and who can modify the artistic look of a game, etc. (thanks to Mauricio Vives for the link)
  • Old, but if you haven’t seen it before, it’s a must: transparent screens.