Is there a way to add a DEM file to a surface with Dynamo?

[rpriceAZEG6]

As it says in the subject line, I’m looking for a way to add a DEM file to a surface using dynamo. My attempts at using the api documentation to write python code in Dynamo has been…discouraging…and I was hoping a tool already exists or someone could give me some pointers with the code. Any help would be appreciated!

[mzjensen]

Hi @rpriceAZEG6,

Are you looking to create a grid surface or TIN surface from the DEM?

[rpriceAZEG6]

A TIN surface from the DEM

[rpriceAZEG6]

@mzjensen Any luck with this one?

[hosneyalaa]

Hi

See this and need some changes

TinSurface from 3D Faces

Hi @JPhil, To get the edges and vertices from the Faces, you would do something like this: [image] However, it will be a very heavy set of operations to deconstruct the faces into vertices and edges and then build the TIN Surface from COGO Points and breaklines. It will be much faster to build the surface from the faces directly using the API. Here’s some code for you to try out in a Python node. [SurfaceFromFaces] import clr clr.AddReference('AcDbMgd') clr.AddReference('AeccDbMgd') clr.…

[Anton_Huizinga]

It is recommended to add a data clip boundary first to the Surface before adding one or more DEM files.

[hosneyalaa]

Never tried to use it before

Thanks for this recommendation

[rpriceAZEG6]

@hosneyalaa You show a screenshot of the SurfaceDefinitionDEMFilesMembers page but I’m having a hard time locating that on the website. Could you post a link to that page?

[david_licona]

https://help.autodesk.com/view/CIV3D/2022/ENU/?guid=9d30e072-4ea5-e414-9a4d-82f235209df3

[rpriceAZEG6]

I’ve attempted to write Python code for this operation but I’ve run into a wall.

[Anton_Huizinga]

I think there is something wrong with the filename. I guess \ must be / or \ in Python. So use:

C:\path to file\filename.tif

or

C:/path to file/filename.tif

Does that help?

[mzjensen]

I would just use a file path node and then have the path as an input to the Python node. Then you don’t have to worry about typos.

[rpriceAZEG6]

Success! Correcting the code with / instead of \ allows my to add a DEM to a surface!

[rpriceAZEG6]

@mzjensen Wanted to leave a special callout to you and your recent episode with office hours. Before watching the class all I could accomplish with the API was crashing C3D. The code above was made using the principles y’all teach in the episode (linked below):

29 - Dynamo and Civil 3D's API

[mzjensen]

Glad to hear it! Nice work

[waga.asanka]

Can someone post the python code for civil 3D 2023 version, this code did not work.