Overview
The Misc group of attributes offers options that are 1) more general in nature, 2) not as essential and 3) experimental. It could also offer those it is not decided where to place them yet.
Bucket Size
3Delight renders the image in small regions called “buckets”. This attribute, expressed in pixels, controls the size of those square regions. The default size is 16, which usually is the best balance between memory usage and performance for 3Delight's render engines. We do not recommend changing this.
Eye splits
Sets the maximum number of geometry splits for objects that cross the “eye-plane”. A more complete discussion about eye-splits can be found in 3Delight-UserManual.pdf.
Opacity Threshold
Specifies a surface opacity value above which a surface is considered opaque. This gives the opportunity for 3Delight to cull more geometry in very dense regions (such as patches of fur). The default value of (0.996, 0.996, 0.996) is a good quality vs. performance trade-off.
Z Threshold
Controls the opacity value of the objects used for the Z output. Only objects with opacities greater than or equal to the ‘Z Threshold’ will be used in the Z output. The main reason to modify the default value of [0.996, 0.996, 0.996] is when using the ‘zmin’ or ‘zmax’ pixel filters with transparent or semi-opaque objects. If this value is set to [0.0, 0.0, 0.0] all objects will be included in the Z output, even completely transparent ones. Note that changing the Z ouptput can affect some raytracing operations. For users familiar with the RenderMan standard, this is the equivalent of the following RiOption:
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