Editing a path object in extruded 3D objects

[Markus Barrera-Kolb]

So you can edit the profile object, including replacing it entirely with a new one (cut the old one, paste a new one), but it doesn't seem you can quite the same thing with the path object -- the polyline/polygon, having been turned into a NURBS curve, can't even be modified with the 2D reshape tool in the way that the original object could have, nor can you delete & replace it with another one. Am I missing something?

Seems like this makes it much tougher to modify the path in relationship to other elements in the drawing, especially because the rest of the drawing disappears once you edit the path object.

[michaelk]

You are correct that you can't edit the path object with the 2D reshape tool.

The way I understand it, when you Extrude Along Path the path object gets changed to a NURBS curve, which is what it needs to be to work in 3D. You can also create a NURBS curve first, then Extrude Along Path. Either way, the path object needs to be a NURBS curve.

But you can edit the path object with the 3D Reshape Tool. And change the path in 3 dimensions.

hth

michaelk

[Markus Barrera-Kolb]

Thanks michaelk -- I found the same thing while playing around with the extruded objects after posting my question. Now I just need to get a bit better at 3D reshaping...

Cheers,

Markus

[islandmon]

When editing the 3d NURBS Path ... keep in mind that the curvature twists based on the bezier Z nodes.

The result is the NURBS Profile rotating around the XYZ curve.

The simplest approach with polygonal profiles is to utilize a flat XY Path.

[michaelk]

True. Unless your profile is a circle (ie. symmetric in any direction) you will notice a twist in the extrude where the NURBS path curves.

Unless, I think, the curve is a fillet. Then the result is a radius corner in the extrude without the twist. I think.

If you do need fancy corners and the twist is a problem, then the Loft Tool may be the way to go.

hth

michaelk

[Markus Barrera-Kolb]

OK, so I think I've gotten my arms around how to edit the NURBS path once the object exists -- what I just ran into yestderday, in my continuted attempt at my first full 3D model, was difficulty in drawing a path object in a side view. I wanted to extrude a downspout along a polyline path, but of course VW wouldn't let me draw a polyline in stacked layers mode, but without stacked layers, I couldn't see all of the building's floors, and without that, I couldn't tell exactly where to draw the polyline. Any suggestions?

Thanks,

Markus

[Pat Stanford]

Make sure you have the Show 2D Objects On Active Layer in the Stack Layer Options.

This will let you use most of the 2D drawing tools with Stack Layers turned on.

[Markus Barrera-Kolb]

Thanks Pat, that makes sense! Of course most of the time I'd probably want to have that option turned off, so that I don't have to look at all the 2D objects I've drawn on the plan layers while I work in 3D -- would it perhaps be possible to set up a shortcut key (Vscript) to toggle this option? I looked in the VW reference appendix, but I didn't see a pref code for it.

[Pat Stanford]

SetPref(95, Not GetPref(95));

[Markus Barrera-Kolb]

Once again, thanks Pat!