"And" <49341109@ntnu.edu.tw> wrote:

> I cannot figure out what is "where the x, y, and z vectors can be specified like
> in a matrix {}"

When we use POV-Ray, we assume that the basis vectors for the Euclidian space we
are modeling in, are defined as:
x = <1, 0, 0>
y = <0, 1, 0>
z = <0, 0, 1>

TdG points out that a "fix" or workaround for scenes made in Moray, which is
right-handed, is to scale the camera "scale <-1, 0, 0>" in order to "flip" the
whole scene and make it look correct.

But fundamentally, what you are doing is changing the x basis vector (relatively
speaking), which affects every point in the 3D space that you are working in,
and therefore every object built using those coordinates.

Making those basis vectors user-definable at their core would add a maximum
flexibility.
In fact, if one really wanted to go nuts, rather than just having scalar values
in the matrix, one could define some sort of function to warp the entire
coordinate space.   I know that sounds crazy, and most people will ask, "WHY
would you want to do that???!", but watch Grant's excellent videos, and you
might get some ideas.


http://www.f-lohmueller.de/pov_tut/trans/trans_400e.htm

Also check out Grant Sanderson's (3Blue1Brown) excellent series on linear
algebra.
https://www.youtube.com/watch?v=k7RM-ot2NWY

Post a reply to this message