After orbiting, panning, and zooming around a model for awhile, the movement within the viewport can get slow and constrained to only a small portion, but I’ve never known what causes this. I’ve known Rhino to behave this way since I was introduced the the software in V4, and I know movement can be restored by selecting any of the ‘zoom to’ commands. Other softwares like Sketchup or 3dsMax don’t seem to have this issue, so I’m curious what is different about the way Rhino navigates a viewport.
Please run the Rhino “SystemInfo” command and post the results.
Hopefully something obvious will show up as a likely cause.
Hello - typically this happens in a perspective view when the camera gets very close to its target. The solution is, usually, to use Zoom Target to reset the camera target. For very close-in work, switch to a parallel projection. Turn on the camera (f6) to see this in action the next time it happens.