With the current situation, I am finally finding time to start looking a bit further into some of the LAS tools that have been appearing over recent builds. My aim is to be able to use M9 for performing a series of QA checks on a whole of region LiDAR supply forming part of New Zealand’s National Elevation Model (https://www.linz.govt.nz/data/linz-data/elevation-data). Thus far, I have found the librarylas dataport used in-conjunction with the ‘Index LiDAR files’ tool to be great additions that work really well. I have found however, that some of my LAS files do not contain projection information so by way of an improvement, it would be nice to be able to set a projection for all files using the index tool as in my case a I know that all the files have the same known projection. Anyway, Using these two tools I have my indexes built and my LAS points linked into the project with the data using the specialised point cloud index. Now I want to start working with it. The first thing I need to do is derive the real LAS X, Y and Z values using VectorValue function: --SQL9 VectorValue(GeomCoordXYZ([Geom], 0), 0) AS [X], VectorValue(GeomCoordXYZ([Geom], 0), 1) AS [Y], VectorValue(GeomCoordXYZ([Geom], 0), 2) AS [Z] Here I am coming unstuck as the linked data schema is read only, so I can’t do what I originally planned which was to create computed columns for these values. My next thought that I might be able to use a query in the project along the lines of: --SQL9 TABLE CALL TableCacheIndexGeoms( ( SELECT VectorValue(GeomCoordXYZ([Geom], 0), 0) AS [X], VectorValue(GeomCoordXYZ([Geom], 0), 1) AS [Y], VectorValue(GeomCoordXYZ([Geom], 0), 2) AS [Z], [CLASSIFICATION], [Geom] FROM [Data Source]::[LAS] ) , TRUE ); To derive the correct X, Y and Z values within the without any data replication. While this appears to work, takes considerable time and I think reverts back to the standard RTree index, thus loses the benefits of the specialised index. I am therefore wondering if I am approaching this all the wrong way and ask if anyone knows of a way to make use of the specialised point cloud index while retaining access to the correct X, Y and Z values. Hopefully this is possible and if so I would be very happy to be pointed in the right direction. Thanks in advance
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