0
$\begingroup$

How can I make a n-sided ( n > 4 ) irregular polygon in Blender?

Context: I import a SVG or DXF file of a paper template (dielines) into Blender. I'd like to make a 3-D 'folded' rendering of it (paper model). Neither SVG nor DXF gives me faces, so I have to make them myself. I try to manually select the vertices or edges, and then fill them. This works quite nicely, until the shape gets too complex (for example because of wholes in the geometry). In the following screenshot from a current project, you see the problem. I can only create a series of triangular faces,... but that is cumbersome. Cumbersome is a bad thing, isn't it? :) I would like to have one face for each 'aspect'/side of my paper model, not five. Is that possible?

enter image description here

This is question/problem I've been struggling with for quite some time. Fortunately, there are enough work arounds, but I'd like to know what the proper solution would be.

I tried dissolving the edges and 'tri to quads' but that didn't help. Neither did beauty-fill of grid-fill.

// Update: -After posting, I saw this post, Cutting hole into a face with a line loop? that mentions 'dissolve limited',... that helps quite a bit already. And it seems that flipping normals is also needed, to keep them al facing the way.

$\endgroup$
  • 1
    $\begingroup$ You can select more than 4 vertices and still fill a face.. It will be Ngon which generally is known to be avoided however if it's flat and you're not aiming to use Boolean and staff then it should be ok. $\endgroup$ – Mr Zak Dec 21 '16 at 13:32
  • $\begingroup$ Hi Mr Zak (?!) Well, no... that doesn't work. Simply selecting a number of vertices and doing "F" doesn't always work. Sometimes is does, sometimes not. I wonder if the resulting shape must mu concave? $\endgroup$ – Ideogram Dec 21 '16 at 13:35
  • $\begingroup$ The left part of my example: if I select all the vertices and then press "F", it won't fill it. The right-hand side is filled manually, selecting triplets of vertices and then doing "F". $\endgroup$ – Ideogram Dec 21 '16 at 13:45
  • $\begingroup$ Do vertices of those tiny quads belong to the edges of the big quad ? Btw I suggest to remove them (might be complex if that's what that geometry consists of). And do you use the latest version of Blender ? Related - blender.stackexchange.com/questions/9140/filling-a-3d-mesh and blender.stackexchange.com/questions/64121/… $\endgroup$ – Mr Zak Dec 21 '16 at 14:05
  • $\begingroup$ @Mr.Zak I was using version 2.77a, but I changed the theme so it looks like version 2.4 :) I found that easier for editing face-less objects. $\endgroup$ – Ideogram Dec 24 '16 at 7:30
2
$\begingroup$

After trying @Mr Zak 's responses (thanks), I feel I should summarize my findings in something more visible than a comment.

Blender should be able to create a polygon from vertices. If it doesn't, the geometry of the vertices is too complex, somehow. To overcome this, fill the shape with less complex planes (tri's, quads, maybe a pentagon) and combine them using "dissolve limited".

If 'dissolve limited' doesn't work, then check the normals of the faces. They should all point the same way. Flip them if needed and try again.

It also helped to remove the edges, while keeping the vertices.

See also Cutting hole into a face with a line loop?

$\endgroup$
0
$\begingroup$

I would use loop cuts and rectangles and parallellograms, like this: enter image description here

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.