Do NOT flip normals in ZBrush

mxhaunted · March 2, 2009, 3:11am

OK, I’ve done a small test to see why the models I’ve been exporting out as OBJs and importing again will cause them to explode.

What I’ve come up with is that somewhere down the pipeline I’ve flipped the normals in “Display Properties” pallet in Zbrush. This causes the model to fail if you export it (for instance to change the UVs) and import it again.

This will also cause the models to fail when using the Transpose Master.

I thought I’d let you know of this as I’ve done a quick search in the forum but nothing came up. Personally, I think this can be quite a debilitating problem.

If anyone has got a fix for this or a workaround then please let me know.

Thanks

MX

Kerwin · March 2, 2009, 6:45am

My solution, take the base object (level 1) .obj out to Silo and make sure it’s unified (e.g. normal aligned correctly.) If it imports with normals flipped into ZB, I flip the normals in Silo and re-import. This usually gets rid of it. I try not mess with the normals once already in ZB and beginning sculpting. If I discover the normals are wonky after I start sculpting, I export the base mesh, correct (as described) and reimport as a new tool. I then use Project All to tranfer my details to the base mesh with clean normals.
-K

mxhaunted · March 2, 2009, 7:26am

Indeed. I think the same process would need to be done using Maya and Max etc.

The Project all functions gets over losing all the detail… just a shame that you’ll lose poly-painted colour as that’s not transferable.

But… I just wanted to point out that it’s not a good idea to use Zbrushes Flip Normal button to fix wrong flipped normals. Hopefully those who read this little thread will know for future reference.

mxhaunted · March 2, 2009, 7:43am

Oh… and something else. Something that’s been happening is that I’ve exported Maya models as OBJs and they have come through to Zbrush with the Normals flipped in the wrong direction.

So I’ve flipped the Normals in Maya and re-exported/imported them and the normals are still facing in the wrong direction even though they should be fixed this time around.

Any ideas?!