Hello Plex.Earth users,
here we are covering the subject of how to create a surface when you have already obtained contours from other sources (e.g survey).
Often, designers are given this information, which, based on a local survey, can be more accurate than the ones available from Google Earth and which can be obtained using Plex.Earth.
So, yes, it is indeed possible to Create Surface by using existing contour lines. It is important however, that the contour lines have elevation information (z) attached to them.
In other words, if they are a 2D representation of the terrain, as is sometimes the case with surveys, then it is not possible. This is because in order to create the surface, the elevation information is crucial in creating the corresponding Surface.
If however they have this information and offer essentially a 3D representation, then the process is the following:
Step 1: Select the "Create Surface" feature of Plex.Earth
Step 2: In the dialogue that appears, on the "Definition" tab, select "Breaklines" and then the "+" to graphically add the elements that are going to comprise the Surface (i.e. contours)
Step 3: Once you have selected the contours
make sure that on the "Contours" tab the box is left unchecked
(you don't want to create new contours from contours!)
and that in the "Triangles" tab, the Import Surface is checked
Step 4: Proceed to click OK and the TIN Surface will have been created normally.
Note, that it might take a while for the process to be completed.