QGIS Create a TIN: Difference between revisions
Content deleted Content added
| (2 intermediate revisions by the same user not shown) | |||
Line 1:
=Introduction=
TUFLOW offers powerful tools for modifying a model's geometry, including generating Triangulated Irregular Networks (TINs) from input data. Alternatively, users can create TINs in QGIS before importing them into TUFLOW. The advantage of this approach is that it allows the user to visualise and review the TINs before they are included in the model.
To demonstrate the workflow, the DEM and GIS files from <u>[[Tutorial_M02#Part_2_-_Other_Topographic_Updates|Tutorial Module 2 (part 2)]]</u> are used as examples. The instructions below refer to the GeoPackage format, but Shapefile format is also supported.▼
To create a TIN, the following files are needed:▼
▲To create a TIN in QGIS, the following files are needed:
* A DEM (raster) layer.
* 2d_zsh (Z shape) layers that define topological modifications:
Line 14 ⟶ 12:
:: If multiple, repeat the <u>[[QGIS_Create_a_TIN#Extract_Elevation_of_Breakline_Vertices_From_IDW_Interpolation | Extract Elevation of Breakline Vertices]]</u> process for each layer. Then, include all outputs in the <u>[[QGIS_Create_a_TIN#Create_TIN_Mesh | Create TIN Mesh]]</u> process.
'''Note:''' All features in the points and breaklines layers must be within the polygon extent.
▲To demonstrate the workflow, the DEM and GIS files from <u>[[Tutorial_M02#Part_2_-_Other_Topographic_Updates|Tutorial Module 2 (part 2)]]</u> are used as examples. The instructions below refer to the GeoPackage format, but Shapefile format is also supported.
<br>
Line 130 ⟶ 126:
<tt><font color="blue">Set Zpts </font><font color="red">==</font> 100 <font color="green"> ! Sets every 2D elevation zpt to 100 metres</font></tt><br>
<tt><font color="blue">Read GRID Zpts </font><font color="red">==</font> grid\DEM.tif <font color="green"> ! Assigns the elevation of zpts from the grid</font></tt><br>
<tt><font color="blue">Read TIN Zpts </font><font color="red">==</font> grid\TIN_Mesh.2dm | 2d_zsh_M02_landscape_002_R <font color="green"> ! Defines areas of complex landscaping</font></tt><br>
| |||