Wish: Hide mesh face edges under definable angle

I’ve started to convert heavier blocks into lower detail meshes to speed up the UI then toggle them out via layers when rendering or when desinging parts that interact with these blocks precisely.

Would be nice to be able to dial out most the triangles… Sortof like how we can control isocurve density. If you could hide edges under a certain angle then you would end up with just the critical edges that show the form in the UI but wouldn’t have all the extra “fill” cluttering things up.

@jeff, this comes up once in a while- the ability to hide say, welded edges in a mesh but show unwelded ones, is how I interpret this anyway - is that possible?


I’m not sure that’s what’s being asked here… I understand that welded edges can be gotten by giving a specific angle/tolerance…However, I think what’s really being requested here is more similar to how silhouettes are computed… In other words, I think what he really wants is edge culling for all edges that pertain to back faces, and thus, only show the edges for all front facing polygons… Although, this could be implemented as a “viewing angle” setting as well, which would simply dial in on “more front facing” polygons… sort of like a focusing a camera on the center of a mesh.

Turning on/off edge display based on “weldedness” is almost impossible (from a performance point of view), unless ON_Mesh can somehow quickly identify which edges are welded and which ones are not…much the same way it does with hidden vertices… Currently, I am not aware of any such construct in ON_Mesh (but that doesn’t mean it’s not there, or that it couldn’t be added).

But, identifying only the edges of front facing polygons is something that can very easily be done… But before anything is done, I think we need exact clarification on what’s being asked here.


Maybe this can help: change your display mode mesh display settings per attached screenshot. This will get rid of all the face triangles that are welded. To cleanup any mesh for display, I would usually run Unweld=0, then Weld=35. Sometimes on messy imported meshes you may need to run RebuildMeshNormals to get rid of some shading artifacts.

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Many thanks all but @Jarek you win. I owe you a beer.

@pascal from a technical perspective why am I seeing such a performance leap by converting NURBS objects to meshes? Aren’t we essentially drawing the render mesh in the viewport? Is it because with the NURBS objects you have to draw curves also? And with the mesh it’s a bunch of straight lines instead?

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I would like to bumb this old issue.
It seems with V6 and the focus on better viewport display and V7 with focus on better mesh tools coming along nicely, the subject of mesh display in the viewport could be reiterated.
Even though the Unweld/Weld + DisplayMinusWeldEdges solution mentioned above does solve some cases it is rather a workaround and fails in many other cases.

I would like to hear if it is possible to implement an option to hide mesh edges under a certain angle and maybe if possible the ability to manually selct to hide certain edges.
Is this possible from a technical level?