Intersect destroys faces, triangulating with hidden geometry

I have found that if I use intersect to trim objects against each other, e.g. to trim a wall into a sloping roof, the faces that remain are triangulated by hidden lines.

If I show hidden geometry, and delete the hidden lines across the faces, I can restore functionality to the faces, but this is time consuming and leaves room for error - it took me quite a while to identify this in the first place.

I consider this a bug, or at least a rather annoying inefficiency - any chance it could be addressed please?


This is often caused by the model being ever so slightly out of alignment. Can I ask if you have Length snapping turned on? If so turn it off and see if it clears up in future models.

I will try it with length snapping turned off, thanks.

However, I work with the axes constantly, to ensure alignment, when I’m modelling.

This is only happening when I use intersect to find the junctions between planes, which are generally not aligned - the point of the process, so I am not convinced that is a cause.

But I will try it, and thanks again.

Yes, looks like that works.

I had to re-make roof insulation layer, and intersect window openings, and no phantom hidden geometry has appeared.

Thanks for the tip!

You’re welcome.
It’s one of those things where people think the snapping helps, but it is actually forcing tiny errors that fall within the tolerance of the face making process, creating cumulative errors throughout the model.

How interesting. That makes perfect sense, and of course, a fundamental of good modelling is minimising errors from the start, rather than adding them!

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