The Quality object properties
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When applied to a polygon mesh primitive rendered as a subdivision surface, enables a method of interpolation for surface attributes that follows the subdivision rules more closely, eliminating many visual artifacts due to bilinear interpolation.
Displace Vertices Only
Enable the vertex level displacement. Geometry is pre-tessellated to a given amount of subdivision prior to running the displacement shader.
Subdivision Steps
Amount of pre-tessellation subdivision steps for the vertex level displacement.