Weird Artefacts on Import

Can someone explain what is happening here

This model was originally crafted in Revit (old version now) and exported as 3D dwg format. I then used SketchUP to convert the model and then imported it to blender 2.79 (using a paid sketchup importer addon). Most of the model has come through fine, but some of my planes are displaying what appears to be a light source, but there is no light source. If I replace the plane with a new one, this doesn’t seem to happen. Obviously I can go through and repair what I must, but would still like to know what is happening here and possible fixes.

BTW have had this on other models that came via SketchUP - and the annoying thing is that it is only one some planes, say +80% of the model imports fine


can you link a file with the issue? could be as simple as a strange material issue

Maybe its glass bsdf, after checking it looks like if you add some refraction depth to the screen space refraction it goes away… Otherwise try this glass(below):

To use screen space refraction you have to enable it in the render settings also, and this is only for eevee.

I have removed the bulk of the model, just showing one of the objects where some of the faces have gone weird. many of them are fixed by using the fill command, but on the irregular shapes the fill cuts across the shape making even more work to fix.

this has happened on more than one model, and I wonder if this is not sure to tri-faces from sketchup (most likely), can’t think that Max would be as messy, but ja cannot say for certain

if you’re talking about the odd face colors (black etc)

that can be fixed by turning off Autosmooth

edit: also, your scene has an environment attached to it, that would account for the lighting as well

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Thank you! This is the problem with Blender (and 3D in general) so easy to get to a level and then you find there is something like Auto Smooth - which I was not aware of. Massive THANK YOU!

Yes I am aware of the environment lighting, that was not the problem - only working to show me the weird artefacts on my planes.