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Overview
The Curve filter enables custom modification of the terrain's altitude using a spline base curve. It works by mapping the height of the terrain to a curve which can then be modified.
Parameters
- Curve
Build a curve to be applied to the terrain. Use 2x LMB to add a new control point and RMB on a point to delete it.
- Source Range
Set the minimum and maximum height values taken from the terrain. The minimum value corresponds to the 0 point on the graph, and the maximum value corresponds to the 1 point on the graph.
Typically, you will want the minimum and maximum values of your terrain (displayed below the height meter on the left) to fall within your source range.
- Destination Range
Sets the outcoming height of the 0 and 1 points of the graph.
Results
 terrain before the curve |  terrain with a custom curve raising the lower areas |