Extrude edges perpendicular(ly?)

Hi all,

How can I extrude the edge of an odd shape so that the extruded shape doesn’t overlap the original. Like this…

[ATTACH=CONFIG]178238[/ATTACH]

  • EDIT: Just “E” to extrude, not ctrl+E.

Thanks in advance for any hints!

That’s a tall order for Blender because some of your edges (like the ones around the “neck” of your shape) will actually get smaller as you go out and there will be cross-over at a certain point… how is Blender going to preempt which edges you most want to preserve? I would first extrude zero distance ([E] key, [0] key, [Enter]) then while the edges are still the active selection, I would scale.

Thanks for your advice, but yeah… that’s what I’m doing at the moment, then dragging the offending points to a better position manually.

I thought there’d be some way to do it, as there should be enough information for Blender to work it out; i.e. the lines that extend outwards from the original shape all bisect the angles of the two edges from which they extend.

(BTW, sorry for making duplicate posts, then deleting the one you just answered! haha)

I’m not sure I understand this correctly without the attachment…
But wouldn’t some variant of the alt-s function, scaling based on the individual vertex directions (I think), be something in the right direction?
I think that’s what you mean with extending the lines based on the original line angles?
I don’t think that can be combined with extrusion at this point. Once the extrude is confirmed, of course, Blender can’t be expected to keep track of the original vertex normals. But it would be nice is hitting alt+s directly when extruding would base it on the original directions.
Fiddling with the F6-settings doesn’t seem to help. Extruding ONE vertex along it’s normal works fine, but not several.
In the context of extruding and G/R/S, it seems like normals are always averaged over the selection. Components can be individually scaled and rotated with Individual Origins pivot mode, but I guess that’s just based on center-points.

Hello.
I am not sure if this is the same problem.
Because I can not see the attached picture.

I think extruding edges perpendicularly is one of the most frequently used tool in Maya.
I hope this feature will be available in blender near future.


1 Like

After selecting the required verts, position the 3d cursor to selection (shift s), then change the pivot point to cursor (period), or could select the option via mouse from the bottom of blender screen.

Scale as required. It often works well for me.

Edit:

Depending on circumstances, the Solidify Modifier might help too.

Sorry I spectacularly stuffed up this post with double-posting and whatnot, but here’s the attachment again for what it’s worth…


I don’t think that can be combined with extrusion at this point. Once the extrude is confirmed, of course, Blender can’t be expected to keep track of the original vertex normals.

Yeah, I still reckon it’s feasible (theoretically) even after extrusion is confirmed, as the shape maintains enough information to expand/shrink each point in the direction which bisects the angle of the 2 edges surrounding the point (that makes sense in my brain, though I’m not sure I explained it very well!)

http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Modeling/Inset-Polygon

Except… after the extrusion, the new vertices aren’t really surrounded by those directional edges anymore. They are either connected by incorrecly scaled edges (like your second picture), or zero-length edges (if they were not moved in the extrusion). But they don’t really “point” in the wanted direction any more. And deriving the wanted direction from their “parent” vertices may (or may not! I don’t really know) be a tricky coding task.

On the other hand… if you, instead of extruding out, insert a thin edgeloop close to the outer edge…then you have correct edge angles to base the scaling on.

Actually… if you select the outer edge ring (ctrl alt click), activate “Individual Origins” pivot mode, and scale… you get the external shape growth you’re after. But obviously also shrinkage in the other direction.