Didn’t know that!
In the past, I saw ‘strange’ images created by artists. But never knew about those extra vanishing points.
I did know that Blender 3D has some features/options to add some lens distortions into the rendered scene. Which creates renders behaving as the 4 … 6 point vanishing lines. This because every real camera lens has some sort of lens distortion. While the exact Blender 3D calculations don’t show at all. Basically, Blender has the function to see distorted. 