Degenerated prisms when producing boundary layers from glued STL's
I can create a mesh with boundary layers from a single, closed STL (as in aneurysm.py) and I can also generate a mesh without boundary layers from glued STL parts (as in glue_and_remesh_stl.py).
However, when I try to do both the resulting mesh is very bad and I get the following warning:
Warning : Degenerated prism in extrusion of volume 2
Minimal working example:
Merge "./cube1.stl";
Merge "./cube2.stl";
Geometry.Tolerance = 1e-6;
Coherence Mesh;
CreateTopology;
Extrude {
Surface { : };
Layers{ {1,1}, {0.1,0.1} };
Recombine;
};
Mesh 3;
There is no warning when generating a single layer with subdivisions (Layers{ {2}, {0.2} }
, for example),
but the prisms are of extremely poor quality.
cube1.stl
solid zone0
facet normal -1 0 0
outer loop
vertex -0.5 -0.5 -0.5
vertex -0.5 -0.5 0.5
vertex -0.5 0.5 -0.5
endloop
endfacet
facet normal -1 -0 -0
outer loop
vertex -0.5 0.5 0.5
vertex -0.5 0.5 -0.5
vertex -0.5 -0.5 0.5
endloop
endfacet
facet normal 1 0 0
outer loop
vertex 0.5 -0.5 -0.5
vertex 0.5 0.5 -0.5
vertex 0.5 -0.5 0.5
endloop
endfacet
facet normal 1 0 0
outer loop
vertex 0.5 0.5 0.5
vertex 0.5 -0.5 0.5
vertex 0.5 0.5 -0.5
endloop
endfacet
facet normal 0 -1 0
outer loop
vertex -0.5 -0.5 -0.5
vertex 0.5 -0.5 -0.5
vertex -0.5 -0.5 0.5
endloop
endfacet
facet normal -0 -1 -0
outer loop
vertex 0.5 -0.5 0.5
vertex -0.5 -0.5 0.5
vertex 0.5 -0.5 -0.5
endloop
endfacet
facet normal 0 1 0
outer loop
vertex 0.5 0.5 0.5
vertex 0.5 0.5 -0.5
vertex -0.5 0.5 0.5
endloop
endfacet
facet normal 0 0 -1
outer loop
vertex -0.5 -0.5 -0.5
vertex -0.5 0.5 -0.5
vertex 0.5 -0.5 -0.5
endloop
endfacet
facet normal -0 -0 -1
outer loop
vertex 0.5 0.5 -0.5
vertex 0.5 -0.5 -0.5
vertex -0.5 0.5 -0.5
endloop
endfacet
facet normal 0 0 1
outer loop
vertex -0.5 -0.5 0.5
vertex 0.5 -0.5 0.5
vertex -0.5 0.5 0.5
endloop
endfacet
facet normal 0 0 1
outer loop
vertex 0.5 0.5 0.5
vertex -0.5 0.5 0.5
vertex 0.5 -0.5 0.5
endloop
endfacet
endsolid zone0
cube2.stl
(single face)
solid zone0
facet normal 0 1 0
outer loop
vertex -0.5 0.5 -0.5
vertex -0.5 0.5 0.5
vertex 0.5 0.5 -0.5
endloop
endfacet
endsolid zone0