Rivers: Creating a Channel

For the river channel, we’ll use the vector data we created in the previous section of this guide to generate a landscape spline, which we’ll then use to modify the layer material and the terrain.

We’re starting with a landscape we created from the Scharnitz DTM data – it’s got the Procedural Landscape Ecosystem material applied.

IMPORT RIVER DATA AS LANDSCAPE SPLINE

With the TerraForm Mode panel open:

• Select the landscape.
• Click Import Lines as Landscape Splines.
• In the Import Vector Lines dialogue navigate to your source folder and Select the river ShapeFile.
• Hit Open.

In the Vector Line Import Options window:

• Check Import Attributes.
• If you’re using Procedural Landscape Ecosystem type ‘Wet_puddle‘ in Layer to define the landscape layer to be used for the river bed. (Alternatively select an appropriate layer from your own landscape material).
• Check Lower Terrain so the landscape will be deformed down to meet the river.
• Check Raise Terrain so the landscape will be deformed up to meet the river.
• In Control Point Import Settings select the HalfWidth attribute.
• We’re going to set Side Falloff (distance over which the landscape will be blended) to 4.5m on either side (450.0cm).
• We’re going to set Left Side Falloff Factor and Right Side Falloff Factor to 0.8, but you might want to experiment with this, depending on your landscape.
• Click Import.

TerraForm imports the river data, using the half width attribute to set the width at each control point and looks like this:

SET DEPTH & DEFORM THE LANDSCAPE

Switch over to the Landscape mode:

• Select the landscape mode using the Modes icon.
• Select the Splines icon on the Manage tab.
• Click on a Control Point in your spline.
• In the Details panel, click Control Points to select all control points in that spline.
• Select the Move icon in the Viewport.

To give the channel some depth, we need to push it below the landscape.

• Hover over the z-axis on the Move Gizmo until it turns yellow.
• [Left-Click] & hold the axis to select it and drag down so it sits slightly below the terrain.

Deform the Landscape to Splines.

• Click Segments in the Details panel to select all segments.
• Click Only Selected in the Tool Settings of the Landscape Mode.

We now have a river channel with variable widths: