Hi @rajaa, it is part of a plugin, with ParallelProjection of Front view. I’ve met the issue with various geometries, including a simple rectangular volume.
I’ve done many tests today and it seems the issue comes from HLDParam.AddClippingPlane(). If I disable this I don’t have these null outputs. Do you know if any changes has been made in Rhino’s recent releases that would impact the clipping planes? Because my code used to work before.
My best guess would be that sometimes objects are computed even when they are on the ‘OFF’ side of the clipping plan, and they end up being Null results.
I can’t send you the plugin since the code is owned by my final user, but I’ll try to do a basic plugin sample.