Ifcopenshell-api geometry.edit_object_placement

herzdame2608

Hey there :-)
I tried to add a new transformation matrix to a specific wall in my ifc file and the wall moved perfectly. My Problem is, that all inherit placements like the placements of the windows in this wall were not updated, so my windows are not in the wall anymore.
Can somebody help me?

Moult

From memory, the edit_object_placement API call actually does reposition all inherited placements. However, this causes a nasty side effect in the case of your situation when you have a window in your wall. Would you like to help modify the API call so that it can selectively determine when to cascade down to inherited placements and when not to?

herzdame2608

I would love to help, but I want to be honest. I don‘t think that my skills are good enough to help.
I read an old post of you that it should update the inherited Placements, but I don‘t know why it does not work for my ifc file. Do you have an idea?

herzdame2608

Is it possible that my window is not related to the wall?
I created the ifc file with revit

Moult

It is precisely because it is updating the inherited placements that you are getting the behaviour you're seeing. What you want is not to update the inherited placements, so that the inherited objects (e.g. windows) move with the wall.

I think it is likely that the window is related to the wall.

I'll see if I can find some time.

herzdame2608

Ooooh okay, now I understand the issue. Thank you so much! I would ne so thankful of you could help me out. Thank you so much.

Moult

Try this and set should cascade to false: https://github.com/IfcOpenShell/IfcOpenShell/commit/21c4433c7507f907288a4a00b8dad26788eff1ca

herzdame2608

Thank you for your help, but the changes did nothing with the windows. They stayed where they were, while the wall moved… :-(

herzdame2608

Here is my code...maybe there is something wrong with it?
ifc_file = ifcopenshell.open("TEST.ifc")

part = ifc_file.by_guid("14PxOZgPT4uuPubh3cNuTR")
old_matrix = ifcopenshell.util.placement.get_local_placement(part.ObjectPlacement)

matrix = mathutils.Matrix(old_matrix)

loc, rot, sca = matrix.decompose()
print (loc, rot, sca)

translation = mathutils.Matrix([[0, 0, 0, 0], [0, 0, 0, 0.5], [0,0,0,0], [0,0,0,0]])

new_matrix = matrix + translation

ifcopenshell.api.run("geometry.edit_object_placement", ifc_file, product=part, matrix=new_matrix, should_cascade=False)
ifc_file.write("Test1.ifc")

Moult

Can you share your file? If it is private, send to [email protected]

herzdame2608

I made an easy test file...here it is... I tried your settings also with other files, but the result was the same.

stephen_l

new_matrix = translation @ old_matrix

herzdame2608

@stephen_l said:
new_matrix = translation @ old_matrix

Thank you for your help, but this is not the issue. I wanted to add the new translation to the old matrix this way, because whe wall moved 50cm in y-direction.

stephen_l

Use
new_matrix = old_matrix @ translation
then, so translation occurs in old_matrix space.
Was mainly referering to syntax issue, where a "+" operator in matrix operations is not valid in blender's matrix context.

Moult

@herzdame2608 sorry, I didn't look carefully at the code and didn't test at all when I committed that. See this fix: https://github.com/IfcOpenShell/IfcOpenShell/commit/edd737aa5db13883cf63c5764e6b5555d058ac65

I renamed the parameter to should_transform_children which makes more sense than should_cascade. So in your case, you want to set it to True. Hope it helps.

herzdame2608

This is awesome! It works perfectly fine. Thank you so much for your help!!!