Clarify VLR/EVLR representation
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It seems to me that the COPC spec currently talks about VLRs but actually conflates VLRs and EVLRs, which may be problematic since the LAS spec clearly distinguishes between those.
Obviously, the info record cannot be an EVLR due to its location requirement, but it might be good to know whether hierarchy and extents must be represented as VLRs, EVLRs, or can be either.
(For anyone wondering, the Autzen sample currently has info and extents as "classic" VLRs, while its hierarchy is an EVLR.)
We tried not to repeat the LAS spec. It says:
A writer who is not concerned with a legacy LAS reader having access to a VLR can elect to use an EVLR, even for predefined VLRs such as Coordinate Reference System(CRS) information.
So, essentially, you can use either. Practically speaking, the hierarchy VLR will always be an EVLR.
Ah, that makes sense. Thanks for clearing that up.