2.5.2 DEM(Digital Elevation Model)

✅ By creating DTM data, you can exclude unnecessary objects (soil, heavy machinery, etc.) when calculating earthwork quantities on a construction site, resulting in accurate quantities.

⚠️ A DTM file cannot be created for a site that does not have a DSM file.

▎Compared to DSM

If you have a DTM file, you can compare it to the DSM, or compare uploaded files and files analyzed within the platform.

① Select the checkbox for the DTM file you created and the menu on the right will appear.

② WhenCompare at onceis enabled, a histogram of the analyzed and uploaded files is displayed simultaneously. When you adjust the horizontal slide of the histogram, the legend of the files being compared adjusts with it.

③ You can adjust the opacity by adjusting the horizontal slider of the histogram or by entering a number.

▎DTM data management

① Select the checkbox for the DTM file you created and the menu on the right will appear.

② Click the Download icon to download a .TIF file with the DTM applied, or click the Trash icon to delete the DTM you created.

③ You can see a histogram of the DTM, and you can view only a specific altitude by sliding the histogram horizontally or entering a number.

④ You can adjust the opacity by adjusting the horizontal slider of the histogram or by entering a number.

⑤ You can modify the DTMs you create.

▎Add a DTM (upload a file)

Upload an existing DTM file.

① Click the +DTM Add button.

② Click the Uploading files button.

③ Attach the files you want to upload with the +Add files button or drag and drop them. Files must have a .TIF extension (TIFF is not possible, please convert to TIF before uploading).

④ Once the job is attached, press the Upload button to register it.

▎Add DTM (manual area creation)

This is how you create a DTM by building the area yourself.

1. Go to the Manually create DTM page.

① Click the +DTM Add button.

② Click the Create it yourselfbutton.

2. Specify a zone for the DTM.

① ClickSpecifying zones button to create a DTM zone.

② Add vertices with the left mouse button, and press Right-click or ESC to finish creating the DTM. You can add vertices multiple times before completing the creation.

- A minimum of three points is required to create a DTM.

- It will flatten based on the vertices of the area you specify, so it is recommended that you draw a slightly wider area than you want.

3. Check the DTM zones you created.

① You can see the DTMs you've created in the left-hand menu, and clicking on the DTM name will display them on the screen.

② You can choose how the height (Z-value) is calculated. There are three: auto-flatten, batch adjust, and custom height. You can find guides for each calculation method by clicking the creation guides.

- A detailed explanation of how the calculation works is written at the bottom of the documentation.

③ You can delete all DTM zones created with Initialise.

④ You can delete the DTM zones you've created individually by clicking the trash can icon.

⑤ You can save temporarily while you are zoning the DTM, and when all the DTM zoning is complete, click the Create DTM button to finish.

▎DTM drafts
 

① Temporarily saved DTMs generate a working indication. Click on the DTM to display its details on the right.

② Click the Modify DTM button to continue with the modification.

▎Edit and delete DTMs

① You can create a new DTM region via the Specify region button.

② You can see the DTMs that have been created, and clicking on the DTM name will activate the vertex buttons in that area so that you can edit them.

③ You can drag an already-created vertex to change its position.

④ Drag the + button on the face to add a vertex wherever you want.

⑤ After modifying the DTM area, click the Done button to reflect the modifications.

⑥ You can change how the height (Z-value) is calculated.

⑦ You can delete all created DTM zones via the ResetReset button.

⑧ You can delete individual DTM zones by clicking the trash can icon.

⑨ You can save temporarily while editing DTM regions, and when you are finished specifying all DTM regions, you can press the Create DTM button to finish.

💡 What is DSM, DTM?

• DSM: Digital Surface Model, data that includes the height of objects above the ground surface.
• DTM: A numerical terrain model, which is pure ground elevation data, excluding objects above the ground surface.

💡 How is the height (Z-value) calculated?

Automatic flattening	Batch reconciliation	Specifying user height
The side that forms a triangle connecting the vertices you specify will be the base. It is recommended that the area you specify is wider than the area you want to erase by flattening it relative to the vertices.	Raise or lower each vertex by a specific value. Adjust the elevation in bulk while keeping the shape of the base intact.	The horizontal plane generated based on the manually entered elevation will be the base. It is recommended that the area you specify is wider than the area you want to erase by levelling to the vertex of the area you specify.