sch@tachyon.UUCP (Steve Holzworth) (09/30/88)
There is a bug in the screen.c routine of Mark's raytracer. Specifically, everywhere he does a malloc, the code is of the form: foo = (Pixel *) malloc (xres * sizeof (Pixel)) + 1; The actual intent is to allocate xres+1 Pixels, thusly: foo = (Pixel *) malloc ((xres + 1) * sizeof (Pixel)); There are three occurences of the former in the code; they should be changed similarly to the later. (Note: I never ran over this bug until I tried to run a 1024x1024 image. It worked fine on 512x512 or less images.) Other than that, its a good raytracer. Congrats, Mark! I'm working on a better lighting model and a better camera model. I'll send them on when (if) I finish them. Steve Holzworth rti!tachyon!sch
saponara@batcomputer.tn.cornell.edu (John Saponara) (09/30/88)
In article <190@tachyon.UUCP> sch@tachyon.UUCP (Steve Holzworth) writes: > [...bug in Mark VandeWettering's ray tracer...] > >Other than that, its a good raytracer. Congrats, Mark! I'm working on >a better lighting model and a better camera model. I'll send them on >when (if) I finish them. I'm certainly interested in extending the lighting model (for starters, positional vs. directional, cosine**power spotlighting, and cone angle cutoff, not to mention the basics like light color). Since NFF seems to be getting used for more than just testing efficiency schemes, these seem important. As far as a camera model, Mark was thinking about the idea of having a sort of NFF++ format: uses NFF, but adds extra stuff (modeling matrices, for example). A preprocessor would convert NFF++ into NFF. The idea is that NFF itself is supposed to be as minimal as is possible, so that anyone can easily read it in. It's as raw as can be. Having a more versatile and user-friendly extended language is fine, but I want to keep NFF itself as simple as possible. Mark and I have been discussing how to define CSG primitives, and I have been thinking about how to add splines with trimming curves. Any advice on these or other extensions you all may have is highly appreciated. I hope to write up a quick description of the NFF format today (Renderman it ain't), and will probably post it this afternoon. Eric Haines (not John Saponara) This `saponara' account is going away - please write to me at: hpfcla!hpfcrs!eye!erich@hplabs.hp.com