Problem
I have a DXF file with a large number of triangles. I’m attempting to create Terrain using the Terrain > From Elements tool.
It is possible to do, but the process takes too long. Sometimes hours.
Solution
The process above takes a lot of processing due to using the element selection tool.
When you are dealing with a large number of elements to create the Terrain, it is advised to use the Graphical Filter tool.
That bypassed the element selection process and creates the Terrain directly.
Example:
Refer to the wiki below on how to create a terrain from a graphical filter
Video: Create Terrain From Graphical Filter