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- surface color (auxiliary): this is the un-shaded and un-illuminated (textured) color of any object. It offers good stability, detection will act between colors and on any texturing color which will be present in the image layer, this means you can use ad-hoc textures to trigger detection of any detail you might want
- geometry ID (auxiliary): the unique color-coded geometry ID (supports also instances). It offers goods stability, and will detect an outilne between different object/instances
- shader ID (auxiliary): the unique color-coded shader/material ID. It offers goods stability, and will detect an outilne between different materials
- depth (auxiliary): this image layer is less stable, being view-dependent. An outline will be detected between regions at different depth
- world space normal (auxiliary): this image layer is less stable, being view-dependent. An outline will be detected between regions where surface normal, in world space, face away
- camera space normal (auxiliary): this image layer is less stable, being view-dependent. An outline will be detected between regions where surface normal, in camera space, face away
- shadow (custom): this offers good stability if the shadow is sharp. Works for delta-light only (spot/point/direct). An outline will be detected around the shadow region.
- face ID (custom): the pseudo-unique color-coded IF for each face. This offers good stability. It detects a "wireframe" for the geometry. In order to export meshes with "face ID" information you need to add delightGeoAttributes> Geometry> Polygons> Export FaceID.
- any combination of geometry and/or materials in a 3delightMaskSet (masks): being black and white masks offer perfect contrast for detectionany additional custom AOV you might need
There is a wide range of artistic possibilities as any number of AOVs (including masks, auxiliary and custom ones) can be used to detect outlines, regardless of how stable they are it is up to you and your artistic purposes to define the look.
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