This page provides information about the Outlines ID render element in V-Ray for SketchUp.
Overview
The Outlines render element stores a mask for both the global and individual material outlines. The outline color and exposure compensation are ignored.
Denoise – Specifies whether to denoise this render element.
Invert Color – When enabled, inverts the resulting render element colors.
Compositing
Outlines is often used for creating cartoon-like renders. This can be achieved in addition with the Diffuse Render Element in a compositing or editing software.