Raytracing is a method of creating high-quality computer-generated images. These images were created using Craig Kolb's Rayshade, which I ported to the Macintosh using Think C.
If you use AOL 3.0, make sure you turn off compressed images in the web preferences, or download the images, to avoid ruining the image quality.
Different image sizes are provided for use as Macintosh Desktop Pictures. Pick the version with the size and color depth that best matches your Monitors settings. Using the right size will avoid "jaggies" that result from resampling the image to match your screen dimensions. Using the right color depth will give you the best looking picture by avoiding color quantization effects. Images are intended to be displayed in 24-bit color ("millions") unless otherwise noted. Those noted as 16-bit color are actually stored in 24-bit color (since they are still JPEG files), but have been pre-dithered so they look good on a 16-bit display. For some reason Desktop Pictures doesn't do a very good job of dithering a 24-bit color image to 16 bits without this little bit of help.
Copyright 1998 Jerry Farm
These images are free for non-commercial personal use; I retain all copyrights.
These images may not be redistributed without my permission.
|Snowman (by Alan Kilian and me)|
400x400 GIF (22K) for 8-bit color
Shows surface textures and shadows.
My first raytraced scene.
640x480 JPG (99K)
640x480 JPG (129K) for 16-bit color
1024x768 JPG (137K)
(No 8-bit version -- it does not look very good with 8-bit system colors)
Once the models were completed, Alan Kilian and I took them into Cray Research (where he worked at the time) and did the final rendering on a Cray Y-MP. Due to the large number of reflected and refracted rays this scene required, the rendering took 18 hours for the original 1280X1024 stereo images. The stereo pair appeared in the ACM SIGGRAPH '90 Stereoscopic Slide Set (1990).
The 1024x768 version of the image was created by scaling the original 1280x960 mono image by 2, effectively oversampling it to 2560x1920, and then scaling by 0.4 to get 1024x768. This avoided jaggies (aliasing artifacts) that appeared if the image was simply scaled by 0.8.
|Raytracers' Recess |
640x480 JPG (76K)
640x480 JPG (110K) for 16-bit color
640x480 GIF (83K) for 8-bit color
832x624 JPG (93K)
1024x768 JPG (115K)
In addition to the background, three other walls, a ceiling, and a door enclose the scene. Even though they are not directly visible, they greatly improve the realism of the scene by adding realistic reflected highlights in the chess pieces. A wide-angle reflection of the room can be seen in the head of the black pawn on the left.
To create the characters in the scene a small C program guygen was written which accepted a list of arm and leg joint angles and created Rayshade-compatible input files. You can download the files for Raytracers' Recess from this BinHex'd Stuffit archive (30K). The archive includes the Rayshade input scene file, plus the source to guygen and it's input files.
For more details, see the Raytracer's Recess Design Notes.
The mono image appears on the cover of the book Computer Graphics, Second Edition, Hearn and Baker, 1994. The stereo pair is also in this book on p. 50, and shows up again in Computer Graphics C Version, Second Edition, p. 50, Hearn and Baker, 1997. The stereo pair appeared in the ACM SIGGRAPH '92 Stereoscopic Slide Set (July 1992).
These versions of Raytracers' Recess have a white bar across the top which is hidden by the menu bar when they are used as desktop pictures on a Macintosh.
Updated: 24 Feb 2000