What is the format of your file? If you have a .ply, there is a new module of GRASS GIS that allows geo-referencing of points cloud in this format: v.ply.rectify. Here are the quick instructions:
Create a .txt file with source and target coordinates; save the file with the same name as the point cloud in the same folder.
Open v.ply.rectifiy in GRASS GIS 7, ...
When not specified, it's the ASCII format that is used by the PLY writer. This impacts the precision of the points.
Header of the original CloudCompare point cloud:
$ head -n16 input.ply
format binary_little_endian 1.0
comment Created by CloudCompare v2.10-alpha
comment Created 03.08.18 14:45
obj_info Generated by CloudCompare!
My error was misunderstanding the offset and scale functionality in liblas.
When defining an offset and a scale the adaptation of the points is performed inside the liblas::Point::SetCoordinates function.
The trick is to set the offset and scale in the header of the writer but still give the SetCoordinates function the original values.
Also the scale ...
Assuming both rasters align (same CRS and cell size*), a first option is:
Retrieve the bridge's boundaries as vector from the bridge raster:
Digitizing raster automatically?
Clip the bridge raster using the Clipper tool or gdalwarp:
Clipping raster with vector boundaries using QGIS?
Clipping raster with an irregular shape?
Merge the clipped raster into ...