> > How do I calculate the vertices of a cylinder, given the coordinates
> > of the (center) end-points? I need to draw a disc, and "point it" towards
> > the other end-point, but I'm totally stuck. The net offers plenty of
> > information on how to calculate the normal vector from a surface, but
> > I need the other way around (i.e. a surface on which <0,0,0> points
> > towards <x,y,z>) .. :-/
> 
>   Well...  If you want your disc to be oriented such as its normal points
> to D from its position P, you just have to have its normal colinear to the
> PD vector.  For instance, use the PD = D - P vector.
> 
>   If it's about a cylinder...  I don't understand the question.

Hmm, after reading through my post again, I admit it's a bit unclear.
I'll
try again;

- I have two end-points point1=<0,0,0> and point2=<x,y,z>
- I create four vertices around each end-point. For the first, this
  would be:
  <-thickness,0,0>,<+thickness,0,0>,<0,0,-thickness>,<0,0,+thickness>
- Now I need to rotate these four, so that they are planar (?) to the
  second end-point. This is where my math skills fail me miserably..

I tried this approach:
  1. rotate vertices atan2(point2.y, point2.z) around the Z axis
  2. rotate vertices atan2(point2.z, point2.x) around Y
and it seems to work if both the endpoints all have Z = 0, but that
wont do in the long run.. :-/

It's pretty basic math, but I never got that far in my studies. ;-)

Any help appreciated. Thanks.

Vidar

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