Presentation Rule – Triangulation¶

Use this presentation rule to generate triangle objects from polygons in the application layer.

Where do I find the dialog?¶

In the Presentation setup for the application layer, select Triangulation as the presentation rule.

Triangulation Methods¶

There are three triangulation methods:

Polygon¶

Uses the geometry of the polygon as the basis for triangulation. This is typically used to display the surface of a road polygon.

Polygon and Break Lines¶

Uses the geometry of the polygon and line objects within the polygon as the basis for triangulation.

Configuration:

Specify the line object under Line object field
Enable Include line objects

This is typically used to generate roof surfaces for buildings with ridge lines.

Polygon and Terrain Grid¶

Uses the geometry of the polygon and points in the terrain grid within the polygon as the basis for triangulation.

Performance

This can result in large and time-consuming datasets with dense terrain grids.

This is typically used to display a land use area draped over the terrain in 3D.

Boundary Functions¶

Choose how the triangle objects should relate to the terrain grid:

None¶

The triangle net drawn is detached from the terrain grid.

Draw Walls Down to Terrain¶

Draws vertical walls from the outer edge of the polygon down to the terrain.

Use Case

Create walls for building shapes.

Perform Terrain Cut¶

The new triangle object performs a cut in the terrain (the grid) and replaces it with the polygon.

Use Case

Display roads from the application layer in the terrain surface.

Advanced Settings¶

Wall Material¶

Select which material to use when rendering wall surfaces generated by Draw walls down to terrain.

Note

Other materials (for example, roof and wall surfaces) are selected in the presentation setup in the previous dialog.

Minimum Point Distance¶

If the distance between points in the polygon and break lines is less than the specified value, the program considers the points identical in the triangulation.

Functions:

Searches for lines within a polygon
Inserts points to connect these lines
Connects ridge lines to building polygons

Practical Example

A building polygon with four corner points and a crossing ridge line:

Before: 4 corner points + 2 points from ridge line
After: One roof surface with 6 points
Bonus: The gable walls are drawn all the way up to the roof edge and presented with wall material