keithsloan52 wrote: ↑Sun Aug 01, 2021 8:44 am
Don't know if it would work, but for me would be an interesting experiment for you to try, would be to create your test case of cube with rounded edges as 12 pairs of hull'ed ( two spheres) all finally union'ed together, with one union. For each edge of the cube you make it a hull of two sphere's. Might have to add in a single cube.
Sounds complex but with OpenSCAD functions/modules not so bad
Good idea, gave this a try, have attached the result below (hull_to_step_experiment.scad). I get this: <class 'Part.OCCError'>: Creation of solid failed: No shells or compsolids found in shape
Should technically be a solid, but perhaps it still has holes e.g. because of rounding issues?
Edit: When removing the polyhedron that creates the faces (so only the hulls with the sphere pairs remains) then I get this:
17:02:03 Traceback (most recent call last):
File "C:\Users\strix\AppData\Roaming\FreeCAD\Mod\OpenSCAD_Alt_Import\OpenSCADHull.py", line 34, in execute
obj.Shape = createHull(obj.Group)
File "C:\Users\strix\AppData\Roaming\FreeCAD\Mod\OpenSCAD_Alt_Import\OpenSCADHull.py", line 468, in createHull
File "C:\Users\strix\AppData\Roaming\FreeCAD\Mod\OpenSCAD_Alt_Import\OpenSCADHull.py", line 331, in hullTwoSpheres
p1, p2 = c4.intersect(c3)
<class 'ValueError'>: too many values to unpack (expected 2)
keithsloan52 wrote: ↑Sun Aug 01, 2021 8:56 am
Not tested for quite a while but I was under the impression OpenSCAD users use minkowski operations to create fillets.
The Alternate Importer ( used to or should ) rather than try and perform any minkowski request, just makes the objects to
be operated in "red". The idea being that you create/develop your model with OpenSCAD and when you want to convert to FreeCAD for what ever reason, STEP file etc, you import into FreeCAD and all the objects you need to fillet are in Red and you can then use FreeCAD to do the fillets.
Hm I could probably have achieved this with minkowskiying a sphere over a polyhedron. In my case that works with hulls (or minkowskis) subtracted from hulls/minkowskis it could be challenging to mark stuff red (see attached screenshot).
It would probably be faster to get me a carving knive and learn how to carve this out of a block of wood instead of "just" trying to come up with a sound formal specification so a machine can do the carving for me. But hey, the way is (also part of) the goal