topic Re: Mesh visibility in Modeling

Mesh visibility

Vojtech Slavik — Thu, 25 May 2023 14:50:38 GMT

Hi, is there some tips how to get know that mesh will be or not visible in 3D ?

For example when I'm bendig too much I can't see mesh and if I I reduce bending it's gonna show in 3D.
Also this happen when I have some holes in mesh.

Do you know whats the right doing it to avoid it

Thanks 🙂

Re: Mesh visibility

Anonymous — Mon, 14 Jun 2021 10:23:10 GMT

Hi Vojtech,

It may be some kind of bug related to micro gaps between coincident arcs.
I can see that there is a node in the middle of an Arc on the bottom one.
Check it the Arcs are really coincident (Curve and Nodes).
Hope this helps.

Re: Mesh visibility

David Maudlin — Mon, 14 Jun 2021 11:17:23 GMT

Vojtech Slavik:

What is probably happening is that the straight edge is crossing the arc near the nodes at the top and bottom of your shape. This creates a self-intersecting polygon that is impossible physically, so cannot be shown in 3D. Sometimes this can be seen by zooming in very close at the node.

David

Re: Mesh visibility

Vojtech Slavik — Mon, 14 Jun 2021 11:20:15 GMT

I don't think there is micro gap, there is must be some limit how thin can be mash or something.
This is example but if I have more complicated ground sometimes is very hard to find which "corner" is doing this problem

Braza wrote:
Hi Vojtech,

It may be some kind of bug related to micro gaps between coincident arcs.
I can see that there is a node in the middle of an Arc on the bottom one.
Check it the Arcs are really coincident (Curve and Nodes).
Hope this helps.

Re: Mesh visibility

Vojtech Slavik — Mon, 14 Jun 2021 11:22:10 GMT

It's definitely this but is there some way how to avoid it... because this information is not visible in 2D

David wrote:
Vojtech Slavik:

What is probably happening is that the straight edge is crossing the arc near the nodes at the top and bottom of your shape. This creates a self-intersecting polygon that is impossible physically, so cannot be shown in 3D. Sometimes this can be seen by zooming in very close at the node.

David

Re: Mesh visibility

Anonymous — Mon, 14 Jun 2021 14:23:11 GMT

Yes. David is correct.
It looks like a, lets say, limitation for the Mesh geometry. As I tested with Slabs and it works fine.
If using a Slab is not an option, as a workaround: Create node in the arc segment, right next to the point of inflection. Then convert the tiny arc segment to a straight one. This would do the trick.
Another solution, is to create a single pavement Mesh that covers also the lawn. Then do a SEO operation to cut the lawn from the pavement.
Hope this helps.

Re: Mesh visibility

Vojtech Slavik — Mon, 14 Jun 2021 14:36:00 GMT

Ok, I understand.

Thanks

Re: Mesh visibility

Lingwisyer — Tue, 15 Jun 2021 01:41:48 GMT

I usually end up chamfering the points of meshes that are like that. It prevents any degen issues and is purely cosmetic, in my case anyway.

Ling.