Thomas WIlliams

Thanks for the reply
I have a rough idea of how all this works now. I was listening to something my lecturer said today about shading. For a standard sphere/cube(smoothed), you can take the vector from the mesh origin to the vertex (& normalize it). Could I use this on other shapes as a 'quicker' procedure for getting the vertex's. This would be really quick as all it is

(vertex - meshOrigin).normalise();

Or would this produce some weird results. The solution that I have at the moment takes way too long. I will give this a try

I will have a go at implementing that and post my result back. This sounds like it could work. I will now have to cycle through each triangle in a given smoothing group to work out the averaged vertex normals. Thank you once again.

I sort of see where you are coming from. I still don't understand how I could make the calculation. So if I had 2 triangles at right-angles joined along one edge (and part of the same smoothing group). what vector would I use for the intensity calculation at the joining vertex? Do I calculate some average of the 2 face normal vectors?

Thank you for the speedy reply