The confusion is totally understandable.
After boolean, the surfaces of the original spheres (before trimming) are remembered. To check, explode the 2 spheres, move apart, you can now use “UntrimAll” command to go back to the original spheres. If you use PointsOn command, you can see the NURBS structure of the underlying surface.
In surface modeling that Rhino uses there are 2 parts to each surface:
- The underlying NURBS surface (clean rectangular topology)
- Trimming information to define the “active” part of the surface.
One of the things PanelingTools allow is to create grids and panels based on the surface “domain”. That always uses the underlying surface to generate the grid. With the bigger grid, you can still use the trimmed surface to trim the panels.
Now, if you need to panel using the polysuface as a whole and ignore the domain of individual surface of the faces, then you can use other workflows also supported by PanelingTools to generate the grid and panels
Here is a breakdown of one workflow that works with two booleaned spheres.
PT_Polysurfaces_Workflow.3dm (1.1 MB)