Complicated Selections in Maya

Sometimes geometry comes into Maya with difficult tessellation; the original designer might have never intended the model to be edited in the first place, or, more likely, was a lunatic.

Take, for example, this knurled surface by aubenc (not a lunatic, AFAIK) on Thingiverse. All those edges on the top surface N-gon trace to a single vertex. Performing an extrude on that top surface is going to get messy and difficult to deal with down the road.

ugly

So, how to delete that collection of edges and replace with a nice clean N-gon?

There’s always the brute force solution, hand-selecting each edge by picking them with the selection tool. This’ll work, but it’s tedious and one always runs the risk of accidentally selecting an edge somewhere else on the model.

I can’t count the number of times a stray edge got accidentally beveled because I selected it this way.

Sometimes it’s possible to switch to an orthographic view, drag-select all the edges on a face from the side, and then CTRL-select the edges you dont want from the other side.

select side A

deselect side

This technique will work with a model that’s oriented nicely along the X and Z axes like this knurled cylinder, but what if you can’t get a clean orthographic selection? Like in this (admittedly fabricated for the purposes of this blog post) case? There are no guarantees that a model you find out there in the wild is going to be well-positioned by the time you get to it.

bad orient

Here’s where Maya’s selection conversion tools become astoundingly useful. First, switch to perspecive view and hit F9. This will put you into component selection mode. Select the single vertex that is common to all the edges you want to delete.

single vert

Hold down the CTRL key and then hit F11. This will convert your vertex selection to faces. (CTRL-F10 will convert to edges, by the way.)

Right click and use the contextual menu to switch to face selection.

context

Hold down CTRL again and unpick the faces that you don’t want in your selection.

faces selected

Then delete the unwanted faces.

border edge

With most models, Polygon-> Fill Hole will give you a nice, clean N-gon if you select a border edge before applying it.

clean

With some fiddling and fuddling and boolean magic, Aubenc’s model became the base for the thumbscrews in Zheng’s GoPro Gubbinses.

Zheng’s GoPro Gubbinses

(Free download, it’s in The Forge, support Open Source design by throwing me a bone yadda yadda yadda.)

What do you think?