[PD] GEM/math: correctly rotating in space

[Frank Barknecht]

Hallo Tebjan,
Tebjan Halm hat gesagt: // Tebjan Halm wrote:

> was tricky, but there is a more or less easy solution if you use two rotate
> objects. first rotate around the z axis with:
> 
> 180/3.14159265 * atan2($f2, $f1);
> 
> then rotate the cube around its y axis with:
> 
> 180/3.14159265 * (acos($f3/$f4)-3.14159265/2);
> 
> where $f4 is the length of the diff vector. the subtraction of half pi 
> (90 degree)
> was found by trial and error ...
> 
> attached is the solution (i hope).

YESSS! Thank you a lot this is working perfectly as intended! 

I just changed:

 180/3.14159265 * (acos($f3/$f4)-3.14159265/2);

to be:

 180/3.14159265 * acos($f3/$f4) - 90;

as that is a bit easier to read any maybe a little bit faster and more
accurate as well. 

Ciao
-- 
 Frank Barknecht                 _ ______footils.org_ __goto10.org__