Hi, I would like to add a spatial reference system in the contexcapture database. I know How to add one in Microstation but how do I add one in Contextcapture?
And if your asking why? it's basicaly because often when I get lidar data (in .las format) it's already been reprojected but to fit the Autodesk reprojection system. Sometime the systems are the same and sometime not. And when the reprojection system do not match in contextcapture when you import lidar data you get the weird tiling-shifting-triangle effect many mention in different post.
So anybody have a clue as to where to start?
Thanks
From CC help:
To Create a Custom Spatial Reference System (SRS)
To find a spatial reference system, you can visit http://www.spatialreference.org/.
PROJ.4
PROJ.4 declaration allows to enter a custom projection system (for instance "+proj=utm +zone=11 +datum=WGS84").
See also http://trac.osgeo.org/proj/wiki/GenParms.
Well Known Text (WKT)
OpenGIS Well Known Text format for coordinate systems can be provided in an attached PRJ file. In such case, enter the projection file path as SRS definition (for instance "C:\projections\myProjection.prj").
GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS 84",6378137,298.257223563, AUTHORITY["EPSG",7030]], TOWGS84[0,0,0,0,0,0,0], AUTHORITY["EPSG",6326]], PRIMEM["Greenwich",0,AUTHORITY["EPSG",8901]], UNIT["DMSH",0.0174532925199433,AUTHORITY["EPSG",9108]], AXIS["Lat",NORTH], AXIS["Long",EAST], AUTHORITY["EPSG",4326]]
Additional data
Some spatial reference systems use external dependencies which, prior to their use, must be installed in the "data\gdal" subdirectory of ContextCapture installation directory.
For instance, a spatial reference system with a custom vertical coordinate system may use a GTX grid to approximate the geoid.
Any well known SRS definition can be entered, which includes PROJ.4 declarations, Well Known Text (WKT), or the name of a PRJ file containing a definition.
Vertical GTX Grid Instruction:
https://communities.bentley.com/products/3d_imaging_and_point_cloud_software/f/contextcapture-descartes-pointools-forum/153294/create-user-defined-system/458045#458045Example of vertical coordinate system setup: https://communities.bentley.com/products/3d_imaging_and_point_cloud_software/f/contextcapture-descartes-pointools-forum/152721/contextcapture-latvian-vertical-coordinate-system-datums
Wow thanks Oto! I will use your .prj file as a start and modify it to my need. In fact I have all the information at hand in Microstation, but somehow Bentley did not include it in Contextcapture.
I'm getting better with reprojection system but clearly I could be spending many hours/days before I could pretend mastering it.