TITLE: That's Impossible NAME: Joe Wise COUNTRY: USA EMAIL: joewise@telocity.com TOPIC: Inner Workings COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT. MPGFILE: h20fall.mpg ZIPFILE: h20fall.zip RENDERER USED: Povray 3.1g TOOLS USED: Povray text editor, Wilbur, mpeg2encode CREATION TIME: Alot HARDWARE USED: Several Pentium Class machines ANIMATION DESCRIPTION: This is my interpretation of the inner workings of the still lithograph, "Waterfall" by M.C. Escher. VIEWING RECOMMENDATIONS: Windows media player seems to work fine. DESCRIPTION OF HOW THIS ANIMATION WAS CREATED: I started by building the still based strictly on M.C. Escher's original lithograph, "Waterfall." The major difference is that I didn't include people and I changed the background. First of all, the problem of perspective needed to be tackled. Because of the way I constructed the scene, perspective needs to be eliminated so that everything in frame is in the same scale, i.e., objects which are the same size and located at different distances from the camera need to appear the same size. That can be done with povray, by using an orthographic camera, but I wanted perspective for the rest of the animation. You can also eliminate perspective by making objects larger as their distance from the camera increases. That seemed really difficult to me so I decided for a third approach. I approximated the elimination of perspective by placing the camera very far away with a very low viewing angle. Then, for the animation, I bring the camera in rapidly and expand the viewing angle. The ground is actually the Grand Canyon. I converted a DEM of the grand canyon into a tga for the height field using wilbur. I'm pretty sure it's not scaled correctly, but the resolution of DEM becomes unacceptable with any more scaling. I didn't include full code for this scene for various reasons, however, in the spirit of the competition, I tried to include all of the non-trivial code, such as how I tackled the camera problems for the first zoom in and last zoom out. I also included the code for the waterfall, which I think could be a decent waterfall with some tweaking. Additionally I included the code for the camera path, which is adapted from a spline path method I found in a book called "Making Movies On Your PC" by David K. Mason and Alexander Enzmann, copyright 1993. I found this method to be VERY useful. It's the only unoriginal code in the scene, and, regrettably, I can't comment on it, as I don't fully understand how it works. However, I tried to make the code more of a discussion so maybe it'll help somebody out there. If you have any questions feel free to email me. Try any of the following email addresses (I don't know which will be around the longest, so I just included them all) joewise@telocity.com joewise@mymoneymentor.com wisej@nationwide.com So, I hope you enjoy this animation. Bet you can't watch it just once.