Terrain Analysis (Elevation, Slope, or Direction)

Terrain analysis helps interpret topographic features by utilizing elevation data alongside other geospatial information like slope and direction. With Plex-Earth, you can easily generate terrain models, visualize landscapes, and make informed decisions without the need for costly site visits.

Step 1. Import a Terrain

An existing dynamic Plex-Earth terrain is required to perform a terrain analysis. To create a terrain, go to the Plex-Earth ribbon → Create Terrain → specify the cover area → choose the Create Terrain Model option when selecting the surface type.

See the full guide here: Create Terrain: Import Elevation Data in AutoCAD/Civil 3D

⚠️ Warning: This feature is not applicable to the AutoCAD/BricsCAD Objects shown below. To use this feature, you will need to import the dynamic Plex-Earth Terrain.

Step 2. Perform an Analysis

1. Open the Collection Manager → locate the terrain → Edit. In the Terrain Editor, go to the Analysis tab → tick Show Analysis.

   

2. Select the type of analysis you would like to perform from the parameters available. Plex-Earth can show three types of terrain analysis.

   • Elevation Analysis - This is the default analysis to be performed by the software if not manually defined at first. The unit of measurement for this analysis will be automatically assigned in accordance with the georeference settings.

   • Slope Analysis - You can choose your desired unit from these options: degrees, radians, grade (%), rise/run, or run/rise.

   • Direction Analysis - The unit of measurement for this analysis can be set to either degrees or radians. The direction, in Plex-Earth, will be based on your drawing units defined in AutoCAD.

3. The steps to conduct either of the three analyses will be similar. After selecting the type of analysis, click on Create Analysis. 

4. Specify the number of ranges and assign a color for the Start and End ranges by clicking on the color and choosing the preferred one from the color dialog box, and click on CREATE.

   

   Plex-Earth will automatically assign the colors for the rest of the ranges, which will create a smooth transition from the color of the first range selected to the color of the last one.

5. Adjust the range values and colors, as needed, then click on Apply.

   

   These maximum and minimum values for each range can be manually edited by replacing the values, as well as the color of each range, to make it more distinguishable from the rest.

   📢 Tip: For better visualization of the analysis, temporarily turn off the contours.

Step 3. Insert Analysis Object

The terrain analysis that was generated is a dynamic element unique to Plex-Earth. To utilize the analysis done even outside a Plex-Earth session, it must be converted into a format that will be recognized by CAD in such cases.

1. To do so, click the Insert button located on the opposite side of Show Analysis and select Analysis object.

   

2. Select how to display the analysis object via the command line. Choose among three options: 3D Faces, 2D Solid, and Mesh.

   

   • 3D Faces – This will import a block that contains all the single three-dimensional faces (triangles) of the terrain model.

   • 2D Solid – This will insert a block containing the faces (triangles) of the terrain model as a solid without the elevation information

   • Mesh - this will insert one mesh (imported as a block) which can even be further exploded to several meshes by range.

As an example, the image below shows how the analysis would look as 3D faces in a Realistic visual style.

Step 4. Add a Legend Table (Recommended)

After performing the terrain analysis, you may want to generate a table containing the necessary information about the analysis.

1. In the Analysis tab, click on Insert → Legend Table.
   

2. Specify a point in the drawing where you want to insert the table. This point will be the top left corner point of the table.

   

   The legend table also functions as a summary or report of the analysis performed on the terrain.

Additional Step. Create labels for Elevation, Slope, or Direction Analysis

Plex-Earth also lets you add labels for the Elevation, Slope, or Direction Analysis you just created. 

1. In the Terrain Editor, go to the Labels tab → enable Show Labels → click on Create → select the label to create.

   

2. Edit the text height, arrow length, arrow heads size (for slope and direction labels), and point size (For elevation analysis). 
3. Tick the label type you want to be visible, and pick the color of your choice
4. Click Apply to generate the changes.

For more details on Terrain Labels, check out this tutorial.

FAQs