Relative Velocity Calculations Scripts???

Hi,

Does anyone have a set of functions to help perform relative angular velocity calculations. In this case what I really want is the relative velocity (i.e. an integer, not a 3D velocity) of the object passing through a flattened cylinder (i.e. looks like a circle), relative to the main axis of the cylinder? From this I could tell from which side the object was coming.

For background see: /54/12/74722/1.html

Tks

I think you are looking for llVecMag ?

actually I think the answer is:

OoC

where
o - represents the DOT product http://em-ntserver.unl.edu/Math/mathweb/vectors/vectors.html#vec7
O - is the velocity vector of the objects passing through
C - a vector (normalised - i.e. magnitude 1) representing the orientation of the cylinders (torus) axis.

I now have to work out how to calculate C. I'm guessing it will be using (a) the IIGetRot() for the cylinder object + (b) knowledge of the normal orientation of the cylinder's central axis in world co-ordiniates (i.e. when IIGetRot() is calculated does it assume a cylinder normally points up, or horizontal [to north or east etc]).

If you happen to know anything about this last point (i.e. calculating C) I'd be interested (otherwise I'll use the suck it and see approach)

Sounds like you want to look at llVecNorm, llGetRot and llRot2Up.

thanks BTW - this put me on track - I did still to write my on Dot Production function [ok - its only one line of code ]