Rays drawn with dashed lines
When the user uses the Trace and Render option, rays with dashed lines can sometimes be seen. These are rays that are leaving a surface (or source) and do not intersect with any other surface in the model (i.e. are heading to infinity).
The length of these lines can be decreased (or increased) in the software preferences. To turn off drawing these rays, set this value to 0.
Below is a picture of the same raytrace, with the above scale factor set to 0.1.