CSG errors on IFC example model

[haroldiedema]

As per request from @agviegas, created a separate issue for this. The original model comes from an IFC wikipedia page and is used as an 'example' model. It seems that a lot of vertices are generated which are not needed.

You can download the model here: https://iedema.me/haus.ifc

[tomvandig]

Hi,

Thanks for posting this issue!

I was rolling a handmade CSG lib, but it's been a pain so I've decided to migrate to another CSG lib. Hopefully this one will last longer 👍

The attached model now looks like this:

There's a small remaining issue with the windows, as each of the voids in this mesh are actually two extruded solids instead of one. Not sure if I should blame the CSG lib or the ifc model now...

[haroldiedema]

This looks pretty much the same as when I used this model using the CLI tool (ifc-convert) to convert the model to a COLLADA file. The z-fighting in the roof and beams were also there 😄

Looks good! 🎉