Using IfcOpenshell and pythonOCC to generate cross sections directly from an IFC file | IfcOpenShell Academy

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#Using IfcOpenshell and pythonOCC to generate cross sections directly from an IFC file | IfcOpenShell Academy

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Original comment by Gareth Boyes on 2015-07-05 17:16:24

Hi

Just exploring Ifcopenshell for the first time and trying to run the examples. It appears that the OCC.Utils module has been deprecated.

Is there a workaround for

section_edges = list(OCC.Utils.Topo(section).edges()) ?

Thanks

[IfcOpenBot]

Original comment by Gareth Boyes on 2015-07-05 17:16:24

Hi

Just exploring Ifcopenshell for the first time and trying to run the examples. It appears that the OCC.Utils module has been deprecated.

Is there a workaround for

section_edges = list(OCC.Utils.Topo(section).edges()) ?

Thanks

Original comment by thomas on 2015-07-26 16:07:41

Hi,

Sorry for the late reply.

The example at http://academy.ifcopenshell.org/using-ifcopenshell-and-pythonocc-to-construct-new-geometry/ has code for both older and newer versions of pythonOCC.

You can try something like this:

while exp.More():

    edge = OCC.TopoDS.topods.Edge(exp.Current())

    exp.Next()```



Hope that helps,



Kind regards,

Thomas

[IfcOpenBot]

Original comment by Wouter Coebergh on 2016-01-13 14:31:03

Hi! for anyone in trouble with the following lines, these fix some issues:

from OCC.TopoDS import TopoDS 

wire = TopoDS.wire(wire_shape)

becomes

from TopoDS import topods

wire = topods.Wire(wire_shape)

And:

surface_area = abs(OCC.ShapeAnalysis.ShapeAnalysis_TotCross2D(wire_data_handle, face))

becomes:

surface_area = abs(OCC.ShapeAnalysis.shapeanalysis_TotCross2D(wire_data_handle, face))

Hope this helps anyone!

[IfcOpenBot]

Original comment by Lukas on 2017-01-19 15:56:13

Hello,

I started using IfcOpenShell and I am amazed by the work taht is happening here.

I tried to run this example as well, but i had a little trouble, hopefully this thread is still somewhat monitored.

First of all the House is not displayed unless the line

>display_shape = ifcopenshell.geom.utils.display_shape(shape)

is included as well, unless I overlooked something?

but the real problem starts when I try to get the intersections between the house and the plane,

the first product in product_shapes (which is the (#35=IfcWallStandardCase('2BvPqvNpvCEhxloyKBrFjE',#5,'South wall',$,$,#71,#49,$,.STANDARD.) class))

throws the exception:

exceptions.AttributeError: 'module' object has no attribute 'BRepAlgoAPI'

I don't really know how to handle this kind of excepion as I just started using python and ifcopenshell, so any help is well appreciated.

Best regards,

Lukas.

[IfcOpenBot]

Original comment by Lukas on 2017-01-19 15:56:13

Hello,

I started using IfcOpenShell and I am amazed by the work taht is happening here.

I tried to run this example as well, but i had a little trouble, hopefully this thread is still somewhat monitored.

First of all the House is not displayed unless the line

>display_shape = ifcopenshell.geom.utils.display_shape(shape)

is included as well, unless I overlooked something?

but the real problem starts when I try to get the intersections between the house and the plane,

the first product in product_shapes (which is the (#35=IfcWallStandardCase('2BvPqvNpvCEhxloyKBrFjE',#5,'South wall',$,$,#71,#49,$,.STANDARD.) class))

throws the exception:

exceptions.AttributeError: 'module' object has no attribute 'BRepAlgoAPI'

I don't really know how to handle this kind of excepion as I just started using python and ifcopenshell, so any help is well appreciated.

Best regards,

Lukas.

Original comment by Lukas on 2017-01-20 09:30:47

Please disregard last comment (can't delete it myself) the import was disabled -.-

Sorry for the trouble.

[IfcOpenBot]

Original comment by Lukas on 2017-01-19 15:56:13

Hello,

I started using IfcOpenShell and I am amazed by the work taht is happening here.

I tried to run this example as well, but i had a little trouble, hopefully this thread is still somewhat monitored.

First of all the House is not displayed unless the line

>display_shape = ifcopenshell.geom.utils.display_shape(shape)

is included as well, unless I overlooked something?

but the real problem starts when I try to get the intersections between the house and the plane,

the first product in product_shapes (which is the (#35=IfcWallStandardCase('2BvPqvNpvCEhxloyKBrFjE',#5,'South wall',$,$,#71,#49,$,.STANDARD.) class))

throws the exception:

exceptions.AttributeError: 'module' object has no attribute 'BRepAlgoAPI'

I don't really know how to handle this kind of excepion as I just started using python and ifcopenshell, so any help is well appreciated.

Best regards,

Lukas.

Original comment by Lukas on 2017-01-20 09:30:47

Please disregard last comment (can't delete it myself) the import was disabled -.-

Sorry for the trouble.

Original comment by thomas on 2017-02-05 16:17:32

No worries, it is still good to have your comment as a reference for others encountering similar issues. Indeed Python submodules need to be explicitly and individually imported. Thanks for leaving a message.

Kind regards,

Thomas

[IfcOpenBot]

Original comment by Siddhesh Chavan on 2017-11-17 11:39:38

How to write IFC-SPF file in PythonOCC?

[IfcOpenBot]

Original comment by Siddhesh Chavan on 2017-11-17 11:39:38

How to write IFC-SPF file in PythonOCC?

Original comment by thomas on 2018-03-24 16:05:33

For others with similar questions: PythonOCC does have an option to write IFC files. You can write IFC-SPF files using IfcOpenShell, for example as discussed in the ticket you opened on github.

Kind regards,

Thomas

[IfcOpenBot]

Original comment by geert on 2020-01-23 15:31:57

The following changes did make the code work for me

Imports:

Delete

• OCC.Utils

• from OCC.TopoDS import TopoDS

• from OCC.TopoDS import TopoDS

Add

• from OCC.ShapeAnalysis import shapeanalysis_TotCross2D

• import OCC.TopoDS

• import OCC.TopExp

• import OCC.TopAbs

And the following edits:

section_edges = list(OCC.Utils.Topo(section).edges())

Becomes:

exp = OCC.TopExp.TopExp_Explorer(section, OCC.TopAbs.TopAbs_EDGE)

    section_edges = []

    while exp.More():

        section_edges.append(OCC.TopoDS.topods.Edge(exp.Current()))

        exp.Next()

--

wire = TopoDS.wire(wire_shape)

Becomes

wire = OCC.TopoDS.topods.Wire(wire_shape)

--

surface_area = abs(OCC.ShapeAnalysis.ShapeAnalysis_TotCross2D(wire_data_handle,face))

Becomes:

surface_area = abs(shapeanalysis_TotCross2D(wire_data_handle, face))

[IfcOpenBot]

Original comment by Gareth Boyes on 2015-07-05 17:16:24

Hi

Just exploring Ifcopenshell for the first time and trying to run the examples. It appears that the OCC.Utils module has been deprecated.

Is there a workaround for

section_edges = list(OCC.Utils.Topo(section).edges()) ?

Thanks

Original comment by thomas on 2015-07-26 16:07:41

Hi,

Sorry for the late reply.

The example at http://academy.ifcopenshell.org/using-ifcopenshell-and-pythonocc-to-construct-new-geometry/ has code for both older and newer versions of pythonOCC.

You can try something like this:

while exp.More():

    edge = OCC.TopoDS.topods.Edge(exp.Current())

    exp.Next()```



Hope that helps,



Kind regards,

Thomas

Original comment by Thi NGUYEN on 2021-03-19 10:10:59

Hi,

I'am using pythonocc-core=7.4.0, python 3.7, ifcopenshell (Anaconda3).

I try to extract the faces of slabs using the following code but it gave me a error: 'Geom_Surface' object has no attribute 'GetObject'.

Do you have any idea? i would appreciate it a lot.

Thank you in advance!

Here is the code that i tested

        topo = TopExp_Explorer()

        topo.Init(slab_shape.geometry, TopAbs_FACE)



        faces = []



        while topo.More():

            fc = topods_Face(topo.Current())

            faces.append(fc)

            topo.Next()

       #Extract the faces of the slab shape

        for face in faces:

            surf = BRep_Tool_Surface(face)



        #Get the plane that represent the face 



            plane = OCC.Core.Geom.Handle_Geom_Plane_DownCast(surf).GetObject()

[IfcOpenBot]

Original comment by Gareth Boyes on 2015-07-05 17:16:24

Hi

Just exploring Ifcopenshell for the first time and trying to run the examples. It appears that the OCC.Utils module has been deprecated.

Is there a workaround for

section_edges = list(OCC.Utils.Topo(section).edges()) ?

Thanks

Original comment by thomas on 2015-07-26 16:07:41

Hi,

Sorry for the late reply.

The example at http://academy.ifcopenshell.org/using-ifcopenshell-and-pythonocc-to-construct-new-geometry/ has code for both older and newer versions of pythonOCC.

You can try something like this:

while exp.More():

    edge = OCC.TopoDS.topods.Edge(exp.Current())

    exp.Next()```



Hope that helps,



Kind regards,

Thomas

Original comment by Thi NGUYEN on 2021-03-19 10:10:59

Hi,

I'am using pythonocc-core=7.4.0, python 3.7, ifcopenshell (Anaconda3).

I try to extract the faces of slabs using the following code but it gave me a error: 'Geom_Surface' object has no attribute 'GetObject'.

Do you have any idea? i would appreciate it a lot.

Thank you in advance!

Here is the code that i tested

        topo = TopExp_Explorer()

        topo.Init(slab_shape.geometry, TopAbs_FACE)



        faces = []



        while topo.More():

            fc = topods_Face(topo.Current())

            faces.append(fc)

            topo.Next()

       #Extract the faces of the slab shape

        for face in faces:

            surf = BRep_Tool_Surface(face)



        #Get the plane that represent the face 



            plane = OCC.Core.Geom.Handle_Geom_Plane_DownCast(surf).GetObject()

Original comment by thomas on 2021-08-07 12:54:55

When using pythonocc 7.4.0 all GetObject() calls should simply be removed. Also don't use Handle_Geom_Plane, but just Geom_Plane.