[Raytrace] Where To Start?

[Bob May]

>>I don't *know* the answer to this, but I think professional level design
programs are generally consistent in surface numbering and sign conventions
as long as you stick to centered systems.
>>
Unfortunately, there are differences between the programs as to the
direction of things.  I'm not familiar with them but have seen notes to that
effect on the SCI.OPTICS newsgroup.  This is because each and every person
that figured out how to do raytracing way back when thought up their
standard directions and the rest of the community has never gotten around to
stating that a particular set of directions is the right way.
I hope this gets to the right path.
Bob May
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bobmay@nethere.com
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