smesh/test/SMESH_MeshioShapes.py

#  -*- coding: iso-8859-1 -*-
# Copyright (C) 2007-2024  CEA, EDF, OPEN CASCADE
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
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#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
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# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
#
# See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
#

# =======================================
# Testing export/import of some simple shapes in different formats with meshio library
#  File   : SMESH_MeshioShapes.py
#  Module : SMESH

import tempfile
from pathlib import Path

import salome
salome.salome_init()

import GEOM
from salome.geom import geomBuilder

import SMESH
from salome.smesh import smeshBuilder

import SALOME

import platform

# Constants
EXPORT_TITLE = 'Export'
IMPORT_TITLE = 'Import'
UNKNOWN_EXCEPTION = 'Unknown exception'
OUTPUT_DIVIDER = '\n==============================================='


geompy = geomBuilder.New()
smesh = smeshBuilder.New()


def make_plane():
    """
    Makes default plane for testing.
    """

    plane = geompy.MakeFaceHW(100, 100, 1)
    geompy.addToStudy( plane, 'plane' )

    return plane


def make_box():
    """
    Makes default box for testing.
    """

    box = geompy.MakeBoxDXDYDZ(200, 200, 200)
    geompy.addToStudy(box, 'box')

    return box


def make_mesh(shape, name):
    """
    Makes a mesh from a given shape.
    """
    res_mesh = smesh.Mesh(shape,name)
    NETGEN_1D_2D = res_mesh.Triangle(algo=smeshBuilder.NETGEN_1D2D)
    isDone = res_mesh.Compute()
    assert isDone

    smesh.SetName(res_mesh, name)
    smesh.SetName(NETGEN_1D_2D.GetAlgorithm(), 'NETGEN 1D-2D')
    smesh.SetName(res_mesh.GetMesh(), name)

    return res_mesh


def file_extensions():
    """
    Returns all files extensions supported by meshio.
    Commented formats should be checked on next meshio release to see if the problem was fixed.
    """

    extensions = [
        '.avs',
        '.bdf',
        # '.cgns', # meshio IndexError: index 2 is out of bounds for axis 1 with size 2
        # '.dat', # meshio ValueError: need at least one array to concatenate
        '.dato',
        '.dato.gz',
        '.e',
        # '.ele', # never returns from meshio convert command
        '.exo',
        # '.f3grid', # meshio IndexError: Replacement index 3 out of range for positional args tuple
        '.fem',
        # '.h5m', # meshio AttributeError: 'list' object has no attribute 'items'
        '.inp',
        '.mdpa',
        '.med',
        '.mesh',
        '.meshb',
        # '.msh', # meshio KeyError: "Illegal ANSYS cell type 'line'
        '.nas',
        # '.node', # never returns from meshio convert command
        # '.obj', # meshio._exceptions.WriteError: Wavefront .obj files can only contain triangle or quad cells
        # '.off', # failed on Windows only
        # '.ply', # Export Warning: PLY doesn't support 64-bit integers. Casting down to 32-bit. Then import failed
        '.post',
        '.post.gz',
        '.stl',
        # '.su2', # meshio TypeError: cannot unpack non-iterable CellBlock object
        # '.svg', # meshio._exceptions.WriteError: SVG can only handle flat 2D meshes
        # '.ugrid', # meshio AttributeError: 'list' object has no attribute 'reshape'
        '.vol',
        '.vol.gz',
        '.vtk',
        '.vtu',
        # '.wkt', # Export Warning: WTK only supports triangle cells. Skipping {", ".join(skip)} then import failed
        '.xdmf',
        '.xmf',
        '.xml'
    ]
    if platform.system() == 'Windows':
        extensions = [ext for ext in extensions if not ext in ['.e', '.exo']] # needs to be digged out - presumably an issue about encoding.

    return extensions

def exception_handle(file_name, errors, operation_type, ex_text):
    """
    Pepares and saves an exception message.
    """

    ext = Path(file_name).suffix.upper()
    msg = '{} {} failed! File name: {}'.format(operation_type, ext, file_name)
    if ex_text:
        msg += ' Exception: ' + ex_text + OUTPUT_DIVIDER + '\n'

    errors.append(msg)


def export_mesh(mesh, file_name, errors):
    """
    Performs an export operatin.
    """

    try:
        print('Export to file: ', file_name)

        # Here we use an empty selected filter to make things simpler
        mesh.ExportMESHIO(file_name, '', mesh)
        return True

    except SALOME.SALOME_Exception as ex:
        exception_handle(file_name, errors, EXPORT_TITLE, ex.details.text)

    except:
        exception_handle(file_name, errors, EXPORT_TITLE, UNKNOWN_EXCEPTION)

    return False


def import_file(file_name, errors):
    """
    Performs an import operatin.
    """

    try:
        print('Import from file: ', file_name)

        ([mesh], status) = smesh.CreateMeshesFromMESHIO(file_name)
        return mesh

    except SALOME.SALOME_Exception as ex:
        exception_handle(file_name, errors, IMPORT_TITLE, ex.details.text)

    except:
        exception_handle(file_name, errors, IMPORT_TITLE, UNKNOWN_EXCEPTION)

    return None


def print_errors(errors):
    """
    Checks if we have got any saved error messages and print them.
    The test failed in this case.
    """

    if not len(errors):
        return

    print('\nErrors:\n')
    for idx, err in enumerate(errors):
        print('{:02}: {}'.format(idx, err))

    print(OUTPUT_DIVIDER)


def perform(mesh, name, errors):
    """
    Exports a given mesh and imports it back for each file format.
    """

    for ext in file_extensions():
        with tempfile.NamedTemporaryFile(suffix=ext, prefix=name) as file:
            file.close() # prevents PermissionError on Windows
            if (export_mesh(mesh, file.name, errors)):
                file.close() # prevents PermissionError on Windows
                import_file(file.name, errors)


def test_box(errors):
    """
    Tests export / import of a mesh for a default box geometry.
    """

    box = make_box()

    mesh_name = 'Test_box_'
    mesh = make_mesh(box, mesh_name)
    perform(mesh, mesh_name, errors)


def test_plane(errors):
    """
    Tests export / import of a mesh for a default plane geometry.
    """

    plane = make_plane()

    mesh_name = 'Test_plane_'
    mesh = make_mesh(plane, mesh_name)
    perform(mesh, mesh_name, errors)


def test():
    """
    Creates meshes from plane and box and tries to export them to a temp files
    and import them back with different formats supported by meshio library.
    Prints errors if we have any.
    """

    errors = []

    test_plane(errors)
    test_box(errors)

    print_errors(errors)
    assert not len(errors)


if __name__ == "__main__":
    test()