To render outputs of some of the methods I use i need display large amounts of Lines and Tubes. This had some issues before but are now all fixed (here, here, and here). In my application I can easily generate 0.5M tracts and subsample them for display. For the type of images I need between 5k and 10k Lines or Tubes to be drawn. Other considerations are:

• The tract coordinates are isotropic and different from the display coordinates
• The display coordinates are anisotropic (but i want the tubes to be round ->Scale)
• Tracts are colored for their local orientation
• Each tract can have a different length but a fixed step size

With 13.2 Generating some tracts with color and defining the Graphics primitives goes very fast and is very straight forward.

When you ask for display the troubles start. As far as i can see the frontend (but not the kernel) is doing some very big computations since CPU is at 50% for most of the wait time. The copying to the GPU is almost instant and once in GPU memory its smooth sailing.

For Lines this generally no problem and displaying 10k lines takes around 5-6s ( both on mac and windows) to display. Once on screen the GPU takes over and rotation is very smooth. For Tubes, 1k is OKish, however drawing only 2k can take up to 60s and if I increase to 4k waiting times are between 90 to 120s. But more annoying drawing can the also cause the frontend to crash (1 out of 4 times, see image) and in some cases even crash my display divers. Again once displayed (if successful) all is very smooth.

I have attached a notebook with some code. I'm curious if anyone can reproduce my problems and more important if anyone has some ideas about making displaying tubes more workable.