I downloaded some Digital Elevation Models from TNRIS and I need to create a TIN from the data. Can anyone help me with this process?
What software are you using?
Mark,
Be aware that TNRIS often provides that LIDAR files with extension LAZ which is a type of zipped LAS file. Geopak cannot open this extension. TNRIS even suggest users to download the freeware called LAStools (https://rapidlasso.com/lastools/)
Also, I would reiterate what caddcop had mentioned about the large amount of data. Geopak runs at 32bit so it struggles with large data files.
BTW, LAStools has some module that converts LAS to TIN or some modules can clip the LAS into small area.
Sorry, I assumed you would be using point cloud to do this anyway.
I was going to use the Create From File tool and the .las files. Or do I have to create a point cloud and create my terrain from that?
I might be wrong here but I think if you use Point Cloud you will not able to distinguish between the different classes. See below:
Class 1 = Unclassified Class 2 = Bare-Earth Ground Class 7 = Low Noise Class 9 = Water Class 10 = Ignored Ground Class 17 = Bridge Decks Class 18 = High Noise
So you would end up with a lot of data that you might not need. Once again, I am not the expert here, so my point here might meaningless. Just trying to help .
I would try first the import option and pray .. also be patient. Geopak might just do the job. it might just take some time.
otherwise, try to import using the point cloud approach and see what you got.
I am absolutely stuck now. I have tried to import .las files with OpenRoads tools and it didn't work. I tried creating a point cloud, but the coordinate system in TNRIS is one that I can't find in MicroStation. I have SS4/OpenRoads/Geopak. I have been searching all over the internet and I can't find an example or explanation for exactly what I am doing wrong or missing in the process.
Jason, I can understand why it's confusing. You actually need to go through the "import" process two times. Once for the las to pointcloud (keyin: pointcloud dialog open) and another for the pointcloud to terrain. What coordinate system is the las in? You can try without the coordinate system in the import dialog... let that stay default for now and verify location of the TIN later. You may want to change the point density of the pointcloud at this point before creating a terrain from it. Once your pod file is made from the import of the las, go to terrain tools and import from point cloud (the 4th icon on the first row Terrain tools ...one that looks like a cloud icon as shown by @mark's comment above) Once that is imported, you can use the context sensitive menu by selecting the surface terrain in the view window and export as Geopak TIN.
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