Remesh creating slivers at edges of geometry

[j00ey]

I've not seen this happen before but I've got some alembic geometry that I'm remeshing in order to simulate and I'm getting tiny sliver prims along the edges of the geometry. I tried deleting all edges below a certain area but it's very tricky to get rid of what I don't want without getting rid of prims that should be kept.

Attached is a scene with a fragment of the input geo. Does anyone know how to avoid the slivers?

Thanks for reading.

remesh_slivers.hiplc

[Noobini]

yes done this...

tho I'm not guaranteeing the cheat will work in you case tho..will have to try it out.

[Noobini]

there...i fixed it, one with defects and with none. The nice thing is, you can go into poly reduce and tweak Percent to keep for instant gratification...

vu_ReduceNiceEdges2.hiplc

[j00ey]

That's a good trick, thanks for that - I'll try it.

Something else I tried was for all the edge points, check if they only have 2 neighbours, group those points then promote that group to prims and blast it. It does a pretty good job except for on the corners. 

[anim]

57 minutes ago, j00ey said:

I tried deleting all edges below a certain area but it's very tricky to get rid of what I don't want without getting rid of prims that should be kept.

if you delete triangles with area exactly 0, it'll get rid of problematic parts especially for further vellum sim, etc, beyond that it's subjective to know which of the visible polygons you don't want

remesh_slivers_mod.hiplc

Edited April 28, 2020 by anim

[j00ey]

1 minute ago, anim said:

if you delete triangles with area exactly 0, it'll get rid of problematic parts especially for further vellum sim, etc, beyond that it's subjective to know which of the visible polygons you don't want

remesh_slivers_mod.hiplc

Hi Tomas

Unfortunately some of them don't have zero area, that's why I was using a threshold but some of the ones I need to keep are tiny too and end up getting deleted. I could do some group combining etc, I just thought there might be a one stop solution. I'll try the above poly expand trick and see if that works on the whole geo.

I appreciate your input as always! 

[anim]

if you decide to use PolyReduce instead of Remesh, you don't need Poly Expand, just set Soft Edges Weight high, like 1000 and maybe Equalize edges to 1 or more if you want to get closer to remesh results, however the difference is that Poly Reduce can only reduce, so you have to start with relatively dense mesh

EDIT: or don't create group for soft edges and use Stiffen Boundaries directly

 

 

remesh_slivers_mod3.hiplc

Edited April 28, 2020 by anim

[j00ey]

Thanks Tomas.

I was just trying something similar to your border group example, I'll try the stiffen boundary method too.

In my case I think remeshing to get a dense mesh gives me a better topology when I do the polyreduce - slower but I can cache the geo out when I've got a good result.