Hi there,
If I have been given a TIN and a point cloud, how can I find out which points are above the surface and which are below, without rasterizing the surface to retain maximum surface fidelity.
Thanks,
Marc
Question
Filter Point Cloud above/below a TIN surface
+23- Safer
Hi @mgg_beca,
I think the simplest process would be to use an Extruder to extrude the TIN by a distance that will encompass the highest point in the point cloud. Then use a Clipper to clip the point cloud by the extruded TIN. Inside points will be above, while Outside points will be below.
If the TIN is a mesh geometry, you may need to use a GeometryCoercer to convert to a composite surface before extruding.
+17- Enthusiast
Hi @mgg_beca,
I think the simplest process would be to use an Extruder to extrude the TIN by a distance that will encompass the highest point in the point cloud. Then use a Clipper to clip the point cloud by the extruded TIN. Inside points will be above, while Outside points will be below.
If the TIN is a mesh geometry, you may need to use a GeometryCoercer to convert to a composite surface before extruding.
Hi @daveatsafe ,
I thought that might be the case, but figured I'd reach out and see if there was a more specific solution. I think there is definitely scope for a transformer to do this.
Regards,
Marc
+10- Enthusiast
I think I’ve done something similar in the past. I think I copied the z value to a new component (Zorig). Then ran through the surface draper. Then I took a difference of the old z and the new z. If its negative is below ground, positive above ground
Login to the community
No account yet? Create an account
An FME Account is required to contribute
LoginEnter your E-mail address. We'll send you an e-mail with instructions to reset your password.