chet@netcom.netcom.COM (Eric Chet) (05/16/91)
Hello
To all raytracing guru's. I would like to ray trace a surface of
revolution. Defined as a bspline curve revolved around axis V. I
would like to do this without converting to a mesh. My question is how
do I intersect my ray with a 2D slice of the revolved bspline curve?
Also the bspline should be defined by N control, points.
V
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Thank you in advance
Eric J. Chet -- chet@netcom.com
--
~
/**************************************************************************
* Eric Chet | Amiga does it better
* chet@netcom.com | Ray Tracing and other graphics techniques
* | "Use what is useful, simply to simplify"
*/stam@dgp.toronto.edu (Jos Stam) (05/16/91)
Eric Chet writes: > To all raytracing guru's. I would like to ray trace a surface of >revolution. Defined as a bspline curve revolved around axis V. I >would like to do this without converting to a mesh. My question is how >do I intersect my ray with a 2D slice of the revolved bspline curve? >Also the bspline should be defined by N control, points. Try the following two references: Kajiya JT, "New Techniques for Ray Tracing Procedurally Defined Objects", Proc SIGGRAPH '83, 91-102. Van Wijk JJ, "Ray Tracing Objects defined by sweeping planar cubic splines", ACM Transactions on Graphics 3(3), 223-237. good luck, Jos (stam@dgp.toronto.edu)