[4.13] Distortion artifacts possibly due to tessellation


I have a project that uses tessellation in one of the textures applied to an object. In 4.11 and 4.12 this worked fine in VR (Oculus and Vive) but in 4.13 I’m getting strange artifacts. Sometimes I see some sort of elongated ghost shadow of the tessellated object appear in the middle of the view, close to the edge, sometimes only on one eye and only visible when looking at certain directions (they slide in and out of view while looking around). I also see a strange distortion “field” on the object texture and around. This looks kind of cool since it seems as if the object is emanating heat and distorting the light around, but it’s not the desired effect. Has someone else experimented these kind of artifacts? I have an Nvidia GTX980 and this is visible in both the Oculus (DK2) and the Vive. When I turn off tessellation, the artifacts are completely gone.



It also seems that the distortion happens mostly (or maybe exclusively) on the right eye and only when Instanced Stereo rendering is on.

I’ve run into some blurry right eye with Instanced Stereo on… Not sure if it’s the same problem…