This is a mesh I've been working on for a while. Basemesh made in maya 100% quads. Screenshot taken from a backup:
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And this is what it looks like as of this morning, when I started up Zbrush:
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I really have no idea what hapened
. Haven't done anything strange with it at all. Still having a minor hope though that this could be fixed - it still looks good on the preview of the file in Zbrush.
//Very greatfull for any help