POV-Ray : Newsgroups : povray.binaries.images : Ha...help : Re: Ha...help Server Time
14 May 2024 05:01:40 EDT (-0400)
  Re: Ha...help  
From: clipka
Date: 5 Aug 2016 14:27:17
Message: <57a4da85$1@news.povray.org>
Am 05.08.2016 um 19:03 schrieb Bald Eagle:

> <1, 0, 0>*(MajorRadius) would be a good vector that would intersect the torus if
> the test ray originates at the origin.

The `inside_vector` has no relation to /any/ points in space whatsoever;
it is a mere direction vector. Even the length does not matter.

> I would presume that if that inside_vector is part of the mesh definition, then
> when the torus gets rotated, the inside_vector gets modified in the same
> fashion.

Effectively, yes.

Technically, no -- rather than actually modifying the entire mesh data,
rotations and other transformations are instead just accumulated in a
pair of matrices, and whenever POV-Ray needs to do math on the mesh it
uses these two matrices to convert input and output data of the
algorithm, so that it can do the math on the original untransformed mesh.


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