Invalid Normals and Strange Render results

[SimonMarks1974]

Hi

I'm having problems with a model imported from an Architect that I am trying to light.

The model is a single editable mesh, and I'm having significant problems with normals. I'm guessing they produced it in a format other than 3D Max, because it comes in with a list of errors;

"MSG 0.0 56 MB error: Invalid normal found on object "V&A proposal" on face 26977, replacing with a dummy normal"

There are about 100 of these, all of which are just different faces of the same object.

These faces fail to render correctly, and I cannot work out a way to fix the problem. the Edit Normal and Normal modifiers don't seem to work. I've unified and flip normals until they are all facing the same way. Nothing seems to (reliably) work.

Any help would be hugely appreciated.

I've attached an screen-grab of the problem.

[big-blue]

I don't know if it will work for you but you can download and try the following script from scriptspot.com :
http://www.scriptspot.com/3ds-max/scripts/unify-flip-normal-polygons

[Anonymous]

Hello,

i had the same issue and i was able to fix it:
Maybe this helps someone.




Select Object

Convert To: -> Editable Poly.

Select all polygons (Ctrl + A).

Edit Geometry -> Detach -> Give new name


This generates more or less a copy of the whole object and
deletes every polygon except of the pivot.
Delete the empty pivot after detaching into a new object.

[SimonMarks1974]

Certainly has helped, not solved all the problems but the rest can be dealt with by amending normals.

Thanks!

[ZParrish]

Thank you for the tip! I had a similar issue with a model I downloaded from Dosch (VirtualArtGalleries-Scene06). It was really starting to bug me. I would detach the element that threw the flag, but the exact same error message came back listing the same Face numbers. The newly detached element with the supposedly bad normals wouldn't trow an error. It was like the geometry was fine, but there was a bad reference in the object itself to specific face numbers.

This worked like a charm!

[CAMedeck]

We have encountered issues with mainly Sketchup models similar to this. As an Editable Mesh, normal directions could not be flipped without either adding an Edit Mesh modifier (but don't collapse it), or converting to an Editable Poly. Doing either of these removes any smoothing, however.

[lilia_fellini]

Thanks Christian Dallinger, worked like a dream!

[arq.landoni]

Hello Christian.  Thank you very much, that tip saved a scene I´ve been working on, and got stuck on that warning while starting the rendereing process! Great job solving it!