Maya - Display hard edges on "Invisible" triangles

Joopson

In Maya, if I have a model in quads, I know it's technically made out of tris, and you can turn on a setting to show them as dotted lines, if you want.

But, even if I harden all the edge normals on the model, the invisible triangles are still displayed as soft edges. Same goes for the viewport setting "Flat Shade All".... It only applies to visible edges (the quads, in my case) But if I convert to tris, and harden the normals, it displays the way I want it to. It helps a lot, when trying to see non-planar faces.

Is it possible to harden the edge normals on these hidden tri edges?


Here's an image showing before and after manual triangulation. Both with hardened normals (but the results are exactly the same even with "Flat Shade All" on)




My wish is for the quad on the left to be shaded like the one on the right.

kodde

I don't think it is.
Left one in Maya should have 4 vertex normals whilst the right one has 6 vertex normals.

Maybe some shader magic could offer you a solution? Not sure where you would start on that shader though. You'd have to identify where that triangle split is. Maybe it has to do which the fact that a quad in Maya doesn't have a definite triangle edge unless you triangulate it, as it shifts depending on where it would be the shortest(i.e. when it deforms. Animation, modelling, etc.).

Bartalon

kodde said:

I don't think it is.
Left one in Maya should have 4 vertex normals whilst the right one has 6 vertex normals.

I agree here.  Visually, Maya doesn't really consider the properties of edges that don't yet exist.  In the case of an all-hardened quad mesh, all triangle edges visible through the "Display Triangle Edges" preview toggle will remain soft edges even after they are created, unless something in the construction history is telling it to become hardened once created, such as with Connect Component and Split Polygon (they have Smoothing Angle parameters, set to 0 by default).  This is also true for any ngon.

If you're just looking for a good way to identify non-planar polygons as you briefly mentioned, then try Display > Polygons > Non-planar Faces or Mesh > Cleanup... with the "Non-planar faces" box checked.

Joopson

Thanks for the information, @kodde and @Bartalon

It's kind of a shame. Honestly, it's more of stylistic importance to me than anything else, though, so it's no big deal. I can always just triangulate the mesh I'm working on, and harden the normals, to see how it looks, and then undo, edit the mesh some more, ad infinitum.

It's the behavior I'd expect when I set it to "Flat Shade All", though, so to me it's a little odd that doesn't do it. I would think it would just turn off soft normal shading entirely, as a display option, for the sake of performance.

Thanks for the heads up about the non-planar faces display option, I hadn't known about that.