I’m working with a pretty large dataset that no factor of Cesium ION’s storage could contain (we’re talking near hundreds of miles of land) and I need to align several pointclouds to the ellipsoid generated by Cesium inside of UE5.
So far I’ve imported pointclouds as a .LAZ, .LAS, and .E57, but some result in an extremely long thread of points (1,1,12200 as an example). When I place the pointcloud into the world, it is heavily misaligned with the georeference and I am unsure how to convert the coordinates and scaling to match up 1:1 with my tilesets hosted locally.
I’ve read a bit into changing the projections via pyproj and laspy, but I am somewhat green in that field.
Currently I am working with Cesium in Unreal to generate the ellipsoid and earth imagery, and the LiDAR Plug-In to import the pointclouds.
Much thanks for reading and providing any support.
Hi @Chris_Morris,
We haven’t used the LiDAR plugin much ourselves, so I don’t know offhand how to solve the problem of lone lines of points that you’re running into. It might be worth posting your question to a more general UE forum.
The misalignment probably (this is an educated guess) comes from the fact that the LiDAR plugin is using a projected coordinate system (likely whatever projection your data uses), whereas Cesium is using true 3D ECEF coordinates. It’s the difference between a planar map (with height), and a globe. If you’re using GIS tools to reproject your data, the one you want for alignment with Cesium is probably EPSG:4978. Unreal has a Georeferencing plugin. I’m not sure if it works with the LiDAR plugin or not, but it’s worth checking out.
By the way, I’m surprised to hear you say that Cesium ion is unworkable for “hundreds of miles of land”. That doesn’t huge (though the resolution matters, of course). I would expect Cesium ion to be able to cope with much larger datasets than the LiDAR plugin.