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@ngunhaSO
Last active Jul 18, 2018
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# retrieve the original stl file
stl_reader = vtk.vtkSTLReader()
stl_reader.SetFileName('path_to_stl')
stl_reader.Update()
stl_poly_data = stl_reader.GetOutput()
# triangulate the stl
triangleFilter = vtk.vtkTriangleFilter()
triangleFilter.SetInputConnection(stl_reader.GetOutputPort())
triangleFilter.Update()
# extract the boundary edge
featureEdges = vtk.vtkFeatureEdges()
featureEdges.SetInputData(triangleFilter.GetOutput())
featureEdges.SetBoundaryEdges(1)
featureEdges.SetFeatureEdges(0)
featureEdges.SetNonManifoldEdges(0)
featureEdges.SetManifoldEdges(0)
featureEdges.Update()
boundaryMesh = featureEdges.GetOutput()
print('get boundary mesh: ', boundaryMesh.GetNumberOfLines())
# init all the container holders for the stiching data
trianglePolyData = vtk.vtkPolyData()
triangles = vtk.vtkCellArray()
points = vtk.vtkPoints()
triangle = vtk.vtkTriangle()
totalLines = boundaryMesh.GetNumberOfLines()
# Start loop thru each edge line from the boundary edge
for i in range(0, totalLines):
cell = boundaryMesh.GetCell(i)
pointIds = cell.GetPointIds()
pointsPerEdge = pointIds.GetNumberOfIds() # expect each edge line has 2 points
p = boundaryMesh.GetPoint(pointIds.GetId(0))
nextPoint = boundaryMesh.GetPoint(pointIds.GetId(1))
# first triangle:
# (xa,ya,za),
# (xb,yb,zb)
# (xb,yb,0)
points.InsertNextPoint(p[0], p[1], p[2])
points.InsertNextPoint(nextPoint[0], nextPoint[1], nextPoint[2])
points.InsertNextPoint(nextPoint[0], nextPoint[1], 1100)
triangle.GetPointIds().SetId(0, i)
triangle.GetPointIds().SetId(1, i + 1)
triangle.GetPointIds().SetId(2, i + 2)
triangles.InsertNextCell(triangle)
# second triangle:
#(xb,yb,0)
#(xa,ya,0)
#(xa,ya,za)
points.InsertNextPoint(nextPoint[0], nextPoint[1], 1100)
points.InsertNextPoint(p[0], p[1], 1100)
points.InsertNextPoint(p[0], p[1], p[2])
triangle.GetPointIds().SetId(0, i + 3)
triangle.GetPointIds().SetId(1, i + 4)
triangle.GetPointIds().SetId(2, i + 5)
triangles.InsertNextCell(triangle)
# clean up the data and ready for writing data into file
trianglePolyData.SetPoints(points)
trianglePolyData.SetPolys(triangles)
trianglePolyData.BuildLinks()
appendPoly = vtk.vtkAppendPolyData()
appendPoly.AddInputData(trianglePolyData)
appendPoly.AddInputData(stl_poly_data)
appendPoly.Update()
cleanPoly = vtk.vtkCleanPolyData()
cleanPoly.SetInputData(appendPoly.GetOutput())
cleanPoly.Update()
writerFinal = vtk.vtkSTLWriter()
writerFinal.SetFileTypeToBinary()
writerFinal.SetInputData(cleanPoly.GetOutput())
writerFinal.SetFileName('data/3D_data/demoparts/test2.stl')
writerFinal.Update()
writerFinal.Write()
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