GeoCue: Classification Lookup VLR

***This VLR was not being written correctly in GeoCue 2017, but was fixed for GeoCue 2020.***

In GeoCue 2017 we added the ability for GeoCue to write the Classification Lookup VLR as provided for by the LAS v1.4 specification. The Classification Lookup VLR is an optional VLR that can be used to convey to non-ASPRS standard classes or user-defined classes when passing around LAS files.

CLASSIFICATION LOOKUP: (optional)
User ID: LASF_Spec
Record ID: 0
Record Length after Header: 256 recs X 16 byte struct len
struct CLASSIFICATION
{
unsigned char ClassNumber;
char Description[15];
};

GeoCue will write this VLR into LAS files it writes whenever the Terrasolid Point Classes List (GeoCue Client -> Setup -> Options -> LIDAR 1 CuePac -> Terrasolid – Project Settings -> Point Classes List:) is not set to the default, “c:\terra\tscan\tscan.ptc”. Conversely, GeoCue does not write the Classification Lookup VLR when the default tscan.ptc file is set since by default that point classes list only contains standard ASPRS classes defined in the LAS specification.

LIDAR 1 CuePac Options Point Classes List

LIDAR 1 CuePac Options Point Classes List

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