Conversion Shaders

The following shaders allow for conversions between data types:

Arnold Data Type Conversions

The following table shows how data types are converted within Arnold itself.

Key:

(empty)	conversion is disallowed/ignored
copy	copy (no need to convert)
expand	all components set to the same source value
shallow copy	for pointer types (pointer, node, array, matrix), copy the pointer, not the actual value
boolean cast	zero means false, non-zero means true, and vice-versa
upcast	smaller integer type just gets stuffed into a larger integer type
downcast	larger integer type gets truncated into a smaller integer type
average	the average of the components are taken

A few notes:

The node type (AI_TYPE_NODE) is currently resolved at scene creation time, and node-to-node shader connections are not formally allowed since they internally are turned into a connection based on the output type of the shader node. However, whenever one wants to pass a node along, they can pass it as a generic pointer type instead of using other mechanisms such as shader message passing. The vast majority of the time, if you are using pointer passing inside of your shaders, however, you should re-think your design.
No automatic conversions exist between integer types and floating-point types.
No automatic conversions exist between enumerations and any other type.