mrmeshpy.boolean can not union these meshes in Python

[6ther]

model0.obj.txt

model1.obj.txt

model2.obj.txt

model3.obj.txt

I union these meshes in Python, but I do not work it out.

[Grantim]

Hello!

The issue is that model3 is not closed:

You can follow this code to unite them:

from meshlib import mrmeshpy as mm

models = []
models.append( mm.loadMesh("model0.obj") )
models.append( mm.loadMesh("model1.obj") )
models.append( mm.loadMesh("model2.obj") )
models.append( mm.loadMesh("model3.obj") )

ptrVec = mm.vectorConstMeshPtr()
ptrVec.resize(len(models))

for i in range(len(models)):
    mm.MeshBuilder.uniteCloseVertices(models[i],0.0)
    ptrVec[i] = models[i]

unitedMesh = mm.uniteManyMeshes(ptrVec)
mm.saveMesh(unitedMesh,"united.obj")

This should work for this case, but in general meshes like these have a lot of coincident planes and model1 has self-intersections

so it is not guaranteed to be successfully united in general

[6ther]

    import meshlib.mrmeshpy as mrmeshpy

    mrmesh1 = mrmeshpy.loadObj('model0.obj')
    mrmesh2 = mrmeshpy.loadObj('model0.obj')
    mrmesh3 = mrmeshpy.loadObj('model0.obj')
    mrmesh4 = mrmeshpy.loadObj('model0.obj')
    models = []
    models.append(mrmesh1)
    models.append(mrmesh2)
    models.append(mrmesh3)
    models.append(mrmesh4)
    mesh_len = len(models)
    rst_mrmesh = models[0]
    for i in range(1, mesh_len):
        mrmesh = models[i]
        hole_edges = mrmesh.topology.findHoleRepresentiveEdges()
        params = mrmeshpy.FillHoleParams()
        params.metric = mrmeshpy.getUniversalMetric(mrmesh)
        mrmeshpy.fillHoles(mrmesh, hole_edges, params)
        union = mrmeshpy.boolean(mrmesh, rst_mrmesh, mrmeshpy.BooleanOperation.Union)
        rst_mrmesh = union.mesh
    mrmeshpy.saveMesh(rst_mrmesh , "result_united.obj")

my code like this. and i do not know that difference between uniteManyMeshes and mrmeshpy.boolean

[Grantim]

Using fillHoles is not recommended for this case, because holes are fully degenerated, and filling them with new triangles will produce degenerated triangles, which might be treated as self-intersections in boolean. So it is better to use uniteCloseVertices which does not produce new triangles but unites degenerated boundaries with duplicated vertices (exactly what is present in this case)

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difference between uniteManyMeshes and mrmeshpy.boolean

In general uniteManyMeshes is optimized version of boolean for several objects, calling boolean instead is OK.