OK, i went ahead and rebuilt liblas with full gdal/geotiff support, and
wrote LAS files with the ECEF WKT that was discussed.

However, lasinfo output doesn't show the actual WKT.  You can try it
yourself on the attached file (ecef_1point.las).

I used this when i wrote file with liblas:

    liblas::SpatialReference srs;
    srs.SetWKT("GEOCCS[\"WGS 84 (geocentric)\",\n\
   DATUM[\"World Geodetic System 1984\",\n\
       SPHEROID[\"WGS 84\",6378137.0,298.257223563,\n\
           AUTHORITY[\"EPSG\",\"7030\"]],\n\
       AUTHORITY[\"EPSG\",\"6326\"]],\n\
   PRIMEM[\"Greenwich\",0.0,\n\
       AUTHORITY[\"EPSG\",\"8901\"]],\n\
   UNIT[\"m\",1.0],\n\
   AXIS[\"Geocentric X\",OTHER],\n\
   AXIS[\"Geocentric Y\",EAST],\n\
   AXIS[\"Geocentric Z\",NORTH],\n\
   AUTHORITY[\"EPSG\",\"4328\"]]");
    header->SetSRS(srs);

However, lasinfo reports this:

  Spatial Reference:
LOCAL_CS["unnamed",
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]]]

It then shows a whole bunch of wrong and/or irrelevant info:

Geotiff_Information:
   Version: 1
   Key_Revision: 1.0
   Tagged_Information:
      End_Of_Tags.
   Keyed_Information:
      GTRasterTypeGeoKey (Short,1): RasterPixelIsArea
      GeographicTypeGeoKey (Short,1): User-Defined
      GeogGeodeticDatumGeoKey (Short,1): User-Defined
      GeogAngularUnitsGeoKey (Short,1): Angular_Degree
      GeogEllipsoidGeoKey (Short,1): User-Defined
      GeogSemiMajorAxisGeoKey (Double,1): 6378137
      GeogInvFlatteningGeoKey (Double,1): 298.257223563
      ProjLinearUnitsGeoKey (Short,1): Linear_Meter
      End_Of_Keys.

It seems that LAS/liblas just doesn't support geocentric CRS.  Any ideas?

Thanks,
Ben

Attachment: ecef_1point.las
Description: Binary data

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