The TIN (Triangular Irregular Network) is a seamless set of triangles representing a surface. In PIX4Dsurvey, the TIN usage is primarily intended to model the ground, from points and breaklines.
The primary input for the TIN generation are points generated with the Grid of Points process. For more information and settings, please see the Grid of points article.
To select the Input grid of points:
- In Processes - TIN, select the generated grid of points in the drop-down menu.
Generate a TIN from the Processes menu.
It is possible to generate the TIN by choosing two algorithms:
- Quick: Triangulates all the grid points together, even on edges, resulting in a convex border fitting holes on the grid's edges.
TIN generation using the Quick algorithm.
- Smart edges: Involves extra post-processing by trying to build a border that fits more closely the shape of the grid points (a concave shape), and remove all the TIN triangles that are outside of this border.
TIN generation using the Smart edges algorithm.
- Use terrain layers as breaklines (Enabled - default): This feature allows the use of polyline, polygon, and marker object types as breaklines if the vector layer is defined as a terrain layer. All layers with the tag Terrain are used.
To define a layer as a Terrain layer:
- In the Content - Layers, right-click on the layer.
- Click Mark as Terrain layer.
Alternatively, it is possible to
- Open the Layer Properties by clicking on the gear button.
- Toggle the Terrain Layer switch.
Toggle on the Terrain layer option (on the left side bar) and enable the Use terrain layers as breaklines option when using breaklines as a constraint for the TIN generation.
The generated TIN can be exported in LandXML format using the following methods:
-  In the Content - TIN panel, click Export or
-  On the top right, click the export icon or
-  From the menu bar, click File - Export.
Export options for the generated TIN in a project.