pythonocc基础使用：导入模型——ifc格式（ifcopenshell）

- 日理万妓 2022-01-19 20:39 941阅读 0赞

借用pythonocc强大的内核功能，我们同样可以读取建筑CAD信息，ifc 格式。  
此处我们将参考ifcopenshell [https://github.com/IfcOpenShell/IfcOpenShell][https_github.com_IfcOpenShell_IfcOpenShell]  
由于我们之前已经安装了pythonocc环境，因此在此基础上直接安装ifcopenshell

conda create -n pythonocc -c conda-forge -c tpaviot -c 3dhubs -c pythonocc -c ifcopenshell -c dlr-sc -c oce pythonocc-core=0.18.2 ifcopenshell python=3.5

如果使用jupyternotebook 还需要使用pythreejs  
\-c conda-forge pythreejs

但是在使用后，会提示在linux 64位上并不能编译，不是很清楚原因。。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjc1NTM4NA_size_16_color_FFFFFF_t_70]  
Using the IfcOpenShell Python interface

$ wget -O duplex.zip http://projects.buildingsmartalliance.org/files/?artifact_id=4278
    $ unzip duplex.zip
    $ python
    >>> import ifcopenshell
    >>> f = ifcopenshell.open("Duplex_A_20110907_optimized.ifc")
    >>>
    >>> # Accessing entity instances by type:
    >>> f.by_type("ifcwall")[:2]
    [#91=IfcWallStandardCase('2O2Fr$t4X7Zf8NOew3FL9r',#1,'Basic Wall:Interior - Partition (92mm Stud):144586',$,'Basic Wall:Interior - Partition (92mm Stud):128360',#5198,#18806,'144586'), #92=IfcWallStandardCase('2O2Fr$t4X7Zf8NOew3FLIE',#1,'Basic Wall:Interior - Partition (92mm Stud):143921',$,'Basic Wall:Interior - Partition (92mm Stud):128360',#5206,#18805,'143921')]
    >>> wall = _[0]
    >>> len(wall) # number of EXPRESS attributes
    8
    >>>
    >>> # Accessing EXPRESS attributes by name:
    >>> wall.GlobalId 
    '2O2Fr$t4X7Zf8NOew3FL9r'
    >>> wall.Name = "My wall"
    >>> wall.NonExistingAttr
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File ".\ifcopenshell.py", line 14, in __getattr__
        except: raise AttributeError("entity instance of type '%s' has no attribute'%s'"%(self.wrapped_data.is_a(), name)) from None
    AttributeError: entity instance of type 'IfcWallStandardCase' has no attribute 'NonExistingAttr'
    >>> wall.GlobalId = 3
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File ".\ifcopenshell.py", line 26, in __setattr__
        self[self.wrapped_data.get_argument_index(key)] = value
      File ".\ifcopenshell.py", line 30, in __setitem__
        self.wrapped_data.set_argument(idx, entity_instance.map_value(value))
      File ".\ifc_wrapper.py", line 118, in <lambda>
        set_argument = lambda self,x,y: self._set_argument(x) if y is None else self
    ._set_argument(x,y)
      File ".\ifc_wrapper.py", line 114, in _set_argument
        def _set_argument(self, *args): return _ifc_wrapper.entity_instance__set_argument(self, *args)
    RuntimeError: INT is not a valid type for 'GlobalId'
    >>> # Creating new entity instances
    >>> f.createIfcCartesianPoint(Coordinates=(1.0,1.5,2.0))
    #27530=IfcCartesianPoint((1.,1.5,2.))
    >>> 
    >>> # Working with GlobalId attributes:
    >>> import uuid
    >>> ifcopenshell.guid.compress(uuid.uuid1().hex)
    '3x4C8Q_6qHuv$P$FYkANRX'
    >>> new_guid = _
    >>> owner_hist = f.by_type("IfcOwnerHistory")[0]
    >>> new_wall = f.createIfcWallStandardCase(new_guid, owner_hist, None, None, Tag='my_tag')
    >>> new_wall.ObjectType = ''
    >>> new_wall.ObjectPlacement = new_wall.Representation = None
    >>>
    >>> # Accessing entity instances by instance id or GlobalId:
    >>> f[92]
    #92=IfcWallStandardCase('2O2Fr$t4X7Zf8NOew3FLIE',#1,'Basic Wall:Interior - Partition (92mm Stud):143921',$,'Basic Wall:Interior - Partition (92mm Stud):128360',#5206,#18805,'143921')
    >>> f['2O2Fr$t4X7Zf8NOew3FLIE']
    #92=IfcWallStandardCase('2O2Fr$t4X7Zf8NOew3FLIE',#1,'Basic Wall:Interior - Partition (92mm Stud):143921',$,'Basic Wall:Interior - Partition (92mm Stud):128360',#5206,#18805,'143921')
    >>>
    >>> # Writing IFC-SPF files to disk:
    >>> f.write("out.ifc")

[https_github.com_IfcOpenShell_IfcOpenShell]: https://github.com/IfcOpenShell/IfcOpenShell
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjc1NTM4NA_size_16_color_FFFFFF_t_70]: /images/20220120/f7c54690f5764f73ba8eb07635765249.png