Flood Level

The Flood Level adjust dialog and Stack function allows for adjustment of a specified lower altitude range of the heightmap to simulate a flood water level change.
The algorithm supports both Flat and Curved flood level types, with Flat simulating a new flat water plane level and Curved simulating a heavy erosion sediment fill.
This function also has a purpose in modifying heightmaps to be more game-player-friendly through increasing the allowable player movement area by providing a flatter main terrain region without making changes to any surrounding mountains on the heightmap.

In this DEM terrain example, a 90% Curve algorithm was applied to the lower 4096 units of heightmap altitude to increase the size and amount of river area, and to simulate filling the river bottoms with heavy sediment to still retain some of their river bed shape.




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