CompuServe Messages

Fred > Actually, you only have to project the poly turnpoints on the screen, right? From there on it's just Bresenham lines and fill algorithms, do you agree? < Yes, exactly, I fiqure the extra calcs on a few points (for aspect adjustments) would be quicker than the slower pixel writes in Mode-X. Of course if there are any very complex objects, things could slow down. > Well, we could try to use the Wu line algorithms, they're supposed to be quite a bit faster than Bresenham's, but I have never actually coded up a Wu line algorithm. < Wu??? Never heard of that one? Is it an optimized Bresenham's? Or a completely new approach to line draws? My programming library is still fairly small (but growing faster than I can afford <g>, and not as fast as I want 🙁 ), next time I'm in town, I'll duck into Barnes & Noble, or if I'm in the neighborhood I'll check out Border's (a local BIG book store). > So what do you mean by studying the database? You mean the method you use for storing the polygon turnpoints? < Right now I want to draw a 3D globe, for the moment I just want to make it solid with light shading, eventually I'll map a random plasma cloud onto it and make it a planet. The globe will be a series of near-square facets. Since each vertex (except at the poles) with be on four facets, AND I want to do my calculations only ONCE for each of the vertices, I think vertices will be in one structure, and my facets will simply index the proper vertices. I also want to take advantage of the radial symetry of a sphere when calculating my normals. > You know, it's occurred to me that you could build ANYTHING out of triangles, so it may be better to work on an engine thet ONLY draws fast triangles. < I had been thinking of this myself as well, the other advantage to triangles is that they are always triangles no matter how they're rotated in 3 space (except on edge, where they become lines), as opposed to squares, which become trapesoids. This means that you can build a triangle engine which would work in all situations. I'm just wondering how efficient it would be to break down everything into triangles. Whatever speed is gained with efficient triangles might be lost with all the extra overhead or having more (although simpler) facets. Jeff P.S. Once I get some code I'll send it. I'll most likely start with Denthor's 3D stuff from TUTs 8, 9 & 14 as a foundation, and then tweak it. I'll try and make my code not too dependant on his stuff, I just want to test my ideas (and structures) before I re-invent the wheel on the 3D stuff. P.P.S. How's your "water" stuff coming along. I used to be a chem major, so if you need any reference materials (I have a CRC among other things) let me know. 2