Mainly readability purposes:
- Having variables called local_payload is ambiguous: does it refer to
LocalPayload type or to a variable be local in a function?
- Some of the functions are used for different ray types, so having the
type case in intersectFunc and filterFunc makes it easier to scan.
For the latter: now it is more obvious that Curve_Intersect_Shadow
expects RayPayload, but Curve_Filter_Shadow expects ShadowPayload.
It might not be a problem currently as ShadowPayload has the same
"header" RayPayload, but it might change in the future. Also, compiler
might optimize fields out from one but not from the other.
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