Hi,
RealityCapture works only with coordinate systems which are clamp-able to WGS84 ellipsoid, and it is still not possible to use geoid heights. In other words, RealityCapture uses only Normal Heights for which the transformation to WGS84 ellipsoid is known. This is due to the coordinate system definitions which we use, which are in the PROJ.4 format.
We are currently working on solution to this, and hopefully other height types will be available in the future.
One of our users managed to do something about that, but bear in mind that this is not our solution.
They wanted to use vertical system 9518 (EPSG), and this is its definition in the epsg.xml file found in the installation folder:
<cs id=“9518” desc=“WGS 84 + EGM2008 height” paramsWKT=“GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],VERTCS["EGM2008_Geoid",VDATUM["EGM2008_Geoid"],PARAMETER["Vertical_Shift",0.0],PARAMETER["Direction",1.0],UNIT["Meter",1.0]]” params=“+proj=longlat +datum=WGS84 +geoidgrids=us_nga_egm08_25.tif +vunits=m +no_defs”/>
They found .gtx file (egm08_25.gtx) which contained information about their coordinate system, and they put it into the Grids folder (“C:\Program Files\Capturing Reality\RealityCapture\Grids”). They also modified the bolded part of the systems definition to:
+geoidgrids=egm08_25.gtx
We did not have resources to test this out, so we are not sure if it works!
On top of that, they managed to combine two systems together (horizontal + vetical). Combined systems were: 32632 + 3855. You can easily find their definitions in the epsg.xml file, and compare them to the combined defition:
<cs id=“32632+3855” desc=“WGS 84 / UTM zone 32N + EGM2008 geoid height” paramsWKT=“PROJCS["WGS_1984_UTM_Zone_32N",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",9.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]],VERTCS["EGM2008_Geoid",VDATUM["EGM2008_Geoid"],PARAMETER["Vertical_Shift",0.0],PARAMETER["Direction",1.0],UNIT["Meter",1.0]]” params=“+proj=utm +zone=32 +datum=WGS84 +units=m +geoidgrids=egm08_25.gtx +vunits=m +no_defs”/>