Starting with ArcGis Pro: create your own source of elevations ( 2)

The difference from the usual modus operandi is that when you click the command, no new window opens. The tool content opens geoprocessor window, and it will stay displayed as long as you do not decide otherwise by performing an operation with the geoprocessor.  

On top of the window, you can find two available tabs for the tool : Parameters and Environments , which work as usual .

Once the features are filled in, you can run the tool by clicking Run, located at the right bottom of the geoprocessor window.
The result ( terre_mer ) is added to the current view.

Now we will create a new “Zone” field that we are going to give information to ” land ” or ” sea “. And we will benefit by looking how the work is performed on the attribute table in ArcGis Pro. As in ArcMap, you open the attribute table by right clicking on the layer in the legend window and selecting “Attribute table”.
A new window opens at the centre below the View window.

To create a new field, you will use the first button on the table button bar.
When you click on the button, the parameterss for the definition of the new field appear in the geoprocessor window. In fact , in ArcGis Pro, all the “flying” windows of ArcMap are now brought back to the geoprocessor window .
Once the field is defined , as usually , by clicking on the field name in the attribute table , you get the “Calculate field” option . The features will , again, open in the geoprocessor window.  

We fill all records with “earth” and select the polygon corresponding to the sea and run the calculation again with ” sea ” as value . As in ArcMap, the field calculator works only on the recordings selected , if any.

Generate DTM for the marine section To generate the marine DEM , we will add the isobaths layer ( corrected from hydro zero as indicated in the article 3D – Functional surfaces – Specific case of the littoral ( earth –sea interface ) )   

In order to create the DTM we will use the command Topo to 3D Analyst Raster.
In the geoprocessor window, click Toolboxes and search the command.

In the geoprocessor window, click Environments. This will let you define the output extent equal to the extent of the Emprise layer .

Also, we define the output size, in our example 75m since it is the cell size of the terrestrial raster . We execute the command and obtain the following DEM :  

Before continuing the creation of the land-sea DEM , which we will see in the next article, we will stop for a moment to see what we just did but this -ci time in 3D.

3D view with the generated DEM

Click the Scene tab. If you had not already done so, remove the Topographic layer. You get an empty window .
If you load the image Aerial in the 3D view you get the following:   

Unlike what you can think at first glance , the image is 3D and draped on a DTM provided by ArcGis Pro by default.
To realize the previous it is enough to increase the hype vertical sight. Click on “Scene” in the legend bar -> Properties -> Elevation surface and change the value by 10, for example.
Then, you will see your image in an exaggerated 3D.

Note that the “sea” section of the image appears flat at level 0 meter . Let’s change the MNT by default for the MNT that we have just created.
To that end you will use the ribbon, MAP tab button Add Preset -> Ground
Point in the DTM file we have created in the first part of the article .

The default DEM is replaced by the new DTM and the view changes immediately :  

Now you can see the opposite of the previous sight: the relief is limited to the marine section,  the ground isflat at level 0.

To manage the different DEMs of a view, you have to use: “Scene” in the caption bar -> Properties -> Surface Elevation
Then by clicking on “Ground” you will get the list of loaded DEMs. You have the up and down arrows to decide which DTM is taken in consideration . As for the layers display, in the legend window it is the one placed highest on the list which is in use.

In the next article we will discuss, how to complete our DTM with the terrestrial section.

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