We are sometimes rendering large lattices, on the order of 6 million beams. The tube filter is too slow. I have seen that there are ways to render lines directly as tubes in OpenGL2 as in this blog post:
https://www.kitware.com/rendering-tubes-and-spheres-in-vtk/
But it appears that the control over the width of the tubes is a single global value, whereas we need to vary the radius of each tube independently. Is there any way to do this?