Drawing a cylinder from A to B

[Wolstan Dixie]

I wish to use the primitive 'cyli.dat' to draw a cylinder from one arbitrary point in 3-space to another arbitrary point in 3-space, ie from (X1,Y1,Z1) to (X2,Y2,Z2) - the points being the centres of the circles defining the two ends of the cylinder. It will have a fixed diameter which I can code in the primitive.

I therefore need a general algorythm which will produce a suitable transformation matrix - I realise there may be more than one, anything that works would do!

I am getting old and slow and understanding transformation matricies is now beyond me - I need the help of a young wiz-kid!

Please!