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Archicad C++ API
About Archicad add-on development using the C++ API.

Surfaces disappear with slightly overlapping walls



We have rendered a few walls with surface paint applied and doors through the Add-On code. However, the building material of the wall appears at the edges of certain walls, as shown in the image below:





However, if we move the wall slightly the surface materials appear correctly. see video.

How can we avoid this? I could not reproduce this issue on the UI by manually drawing the wall so suspecting it has something to do with setting some field in the wall element.


Attaching the project.


Archicad Version 27


have you tried the align tool 😃 i tried with your file and it worked.

here is how i did it

- aligned the two outer walls where the issue was

- then aligned the vertical wall into the other outer walls.


Hi @kency,

I see you can get the desired result by changing the BM for the radial walls to a different material (even if you copied the same BM of the outer walls) only it should have a lower priority than the material of the outer walls, that will solve this connection issue, hope that helps.



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Thanks for the reply @_JJ_ and @Mahmoud Qenawi , Please note that the query is asked under the C++ Add-On API board. The project has been rendered through code. So is there any field or method through the C++ API that can be used to avoid this issue and also at what scenarios does this happen?


@Mahmoud Qenawi we would like to pick the same building material for all the walls.



The wall reference lines are not joining end to end.




Clean them up and the walls trim properly.





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Are these walls defined by length then radially arrayed? Given the walls appear to be overshooting their intersection, maybe check the math of your cord length? My guess is that you are calculating to the outside face without taking into account the reference line offset. ie. Your input radius is incorrect.




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