I was asked to produce an Archicad compatible 3D terrain model for a client. Now all the tutorials on the web focus on creating "site models" from "surveyors data", that is from 3D points. Since I have the original data (a dense grid), i could do the meshing better than the Archicad mesher could. Also it would be inconvenient for the client to have to do that extra step (meshing). What format could i deliver a mesh in so that the client could easily use it as a 3D site model with minimal extra work. I do not have Archicad, but I can produce most file formats (dxf/obj/stl etc..) except proprietary ones.
Rephrasing: What format would you like to receive 3D topography in?
The problem with delivering the topography a in these other formats (dxf/obj/stl etc.) is that the terrain will come in as a fixed Object that cannot be edited, not an editable Mesh. It would be best to provide a text or XYZ file that can be used with the Place Mesh from Surveyor's Data... command which will create an editable Mesh. The help center guide is here: Other Formats Opened by ARCHICAD.
Either method utilizes some sort of import command, so from the user's point of view the effort would be similar (import and convert to Object, or open txt file and convert to Mesh). So I don't think the user is being burdened this way. Good luck.