Re: Rotation matrix definition

[Farzad Torabi]

Adding to that, that I'm not a student,

My doubt is about the order of rotations, given that from the new Cs, I only have the direction of one of its axes. 

Il gio 21 nov 2019, 10:34 Carlo De Falco <address@hidden> ha scritto:

> Il giorno 21 nov 2019, alle ore 10:11, Farzad Torabi <address@hidden> ha scritto:
>
> I need to convert the translations + rotations from global coordinate system into a new coordinate system that is translated+rotated from the global one. How do I obtain that ?
>

This sounds like homework, is it?

If so, we usually avoid providing directly solutions to students' homework,
(and it would be particularly inappropriate in this case as we are in the same University)

That said, I think it is OK to provide some pointers.

Affine transformations in R^3 can be conveniently represented as (4x4) Matrix times (4x1)
vector multiplications using homogeneus coordinates, you can find the theory about this
in any undergraduate text on linear algebra and geometry.

The package "nurbs" contains utility functions "vecrot" and "vectrans" that help you construct
the appropriate matrices representing an affine transformation.

hope this helps,
c.