Point rotation

THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED
On 29/01/2003 at 08:55, xxxxxxxx wrote:
User Information:
Cinema 4D Version: 8.012
Platform: Windows ;
Language(s) : C.O.F.F.E.E ;
Hi,
I have 3 points (P1, P2 and A). They are lying in one plane, but not
along a world axis.
P2 should be rotated around A that vector P2A ist pointing in the
same direction like vector P1A. I have the rotation axis and can
calculate the angle. But I don´t know the direction of the rotation
(angle is always positive). Is there a formula to get this right?
Thanks.

THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED
On 29/01/2003 at 14:43, xxxxxxxx wrote:
I assume you want a transformation so that you can rotate other points as well. (Otherwise just assign P2 = A + vnorm(P1  A) * P2.)
What you could do is to get the rotation axis by the cross product "vcross(P2A, P1A)". Then the rotation axis together with the angle given by asin(vlen(vc)) will always rotate P2 to P1. (I think... :)

THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED
On 03/02/2003 at 05:32, xxxxxxxx wrote:
Thanks. This works once again :).
But what to do if i want to get the average angle between two polys. I´m trying to rotate one poly (in one plane) so that it´s edges are aligned to the edges of another poly. I can calculate the angles between all edges, but how do I put them together? Adding the edges(vectors) of each poly and taking the cross product didn´t do the job.
Thanks in advance.