How to Fix Edge Loop Not Going All the Way Around in Maya 2019
It’s very annoying to try to insert an edge loop and see the tool to not go all the way around, it suddenly stops in a seemingly random place of the mesh. There are a few very common situations in which this happen, in this article, you’ll learn strategies to identify and overcome them.
Why is it happening?
You can only insert edge loops on quads, the most common issue is trying to insert an edge loop on a series of quads that has a triangle at the end of it.
It’s also very common to have ngons (polygons with 5 or more sides) preventing the insertion of an edge loop.
Sometimes those ngons look like a quad when viewing in edge mode. Switch to vertex mode to better see them, you could also detect this in edge mode by clicking on the edges, they would only be partially lit.
There’s also the possibility that you have unconnected faces (being quads or not) that look connected, hindering the loop insertion. Those are impossible to recognize at first glance.
To be able to easily see when this happens you can enable Display Borders on your Mesh Component Display using the Attribute Editor.
Aside from triangles, ngons, and unconnected faces, there’s also the possibility that you have duplicate vertices and faces sitting on top of each other clouding your view. Don't worry, this article will present a strategy to detect and fix these other issues too.
Most common causes for creating “hidden” ngons
These hidden ngons, on my experience, mostly happen by deleting edges pressing Delete (or Backspace), leaving all the vertices behind. You can easily see if that’s the case by pressing F9 and taking a look at your mesh vertices. If you want to delete the edges and also it’s associated vertices you need to delete them by pressing Ctrl + Delete (or Ctrl + Backspace)
There are also some really odd ngons that look much more like 2 or 3 regular faces. Those are usually caused by boolean operations. You can identify those by hovering your mouse over the problematic area of your mesh with face selection on (F11) or by displaying the face centers.
To fix this issue, I suggest deleting the weird face to later recreate the faces you need using the Append to Polygon tool.
It's possible to display the face centers enabling the Display Center face attribute of your shape node Mesh Component Display setting, this can be done using the Attribute Editor, similarly to what has been done to Display Borders. If you want, you could have it on by default to newly created objects by going to [Windows > Settings/Preferences > Preferences], inside it go to [Display > Polygons]
Most common causes for creating duplicate faces, vertices, and faces sitting on top of each other
On my modeling experience (that varies for according to the style used by the modeler), one of the probable causes for creating duplicate faces are boolean operations.
Not only the immediate result of the boolean, a lot of times those are not the direct cause for the duplicate faces, but when we try to fix the weird meshes, especially the big ngons, or the faces with lots of crossing lines.
One very important thing to avoid doing whenever a boolean is used is letting faces sitting on top of each other caused by snapping. This will result in bad geometry that’s hard to fix.
How to cleanup duplicate faces
First, try using the Cleanup [Mesh > Cleanup...] operation. Press the little square for options. In Maya’s terminology, duplicate faces are called Lamina Faces.
If using Cleanup wasn’t enough, your next step should be to select all your vertices and merge them. Finally, as a last resource, select all faces of the pathological area and delete them, if you can still see a face it’s because you had a loose face there. Reconstruct this area using the Append to Polygon tool.
What if I need to insert an edge loop and I’d like to keep my triangles?
On that case, you’ll need to resort to the Multi-Cut tool. Insert edge loops by holding Ctrl and clicking, as usual, but create the connections in the triangles manually.
In a strict sense, if it has 3-way junction, this structure is not considered an edge loop. See more at https://web.archive.org/web/20110324081434/http://wiki.cgsociety.org/index.php/Edge_Loop.
And last, if you tried all this and still can’t properly insert and edge loop it could be a bug in the Maya software. Deleting the object’s construction history might make Maya be able to do it again.
- Edge Loop
- Duplicate faces (laminar faces)