Center Osnap not working

I’ve just installed R6 SR2, and I’m having trouble with the center osnap. In the attached file, the extrusion was made from the polyline. If I try to snap to the centers of the arcs, it works fine on the polyline but only on some of the arcs of the extrusion (example: the arc in the center ‘lobe’.)

One clue I’ve found is that if I import that same polyline into an inches template and then extrude, I don’t have the same issue. once extruded loses center points.3dm (99.5 KB)

Another clue, maybe? This seems to happen to curves after I use curveboolean. See attached. In the curves in the middle, I can’t snap to some of the centers. If I do it all avoiding curveboolean, I can snap to centers. center points problem.3dm (124.7 KB)

The CurveBoolean turned some of the sections into segments that are not recognized as arcs. You could dig through the object properties details to verify this if you were really bored.

The fix is easy:
Run SimplifyCrv on those polycurves, they will get their arc properties back and Center osnap functionality will be restored.

Great. Can Rhino do that automatically? I don’t remember having this problem in V5, and I just imported this to v5 and my results were center-snap-able.


Thank you

Hi Peter - you can get around this, in your example at least, with this setting-


Thanks - I don’t feel like those are approximate (but I guess that’s why it’s on the bug list.) I’m not sure I want to snap to approximate centers, but I’ll try it out.