Erosion

RustEdit Pro

The nodes in the Erosion category of the Terrain Graph's Add Node menu. Round sockets carry maps and square sockets carry single values. See Graph editor.

Flow

Where rain water collects and runs: a flow map and a river mask.

Inputs

Input	Kind	Default	Notes
Height	Map
Detail	Choice	Low	How finely the water is followed. Higher is slower. Options: Low, Medium, High.
Threshold	Number	0.6	Flow above this counts as a river. Slider from 0 to 1.
Softness	Number	0.05	How gradually the river mask fades in around the threshold. Slider from 0 to 0.5.

Outputs

Output	Kind
Flow	Map. How much water passes each point, from 0 (none) to 1 (a big river).
Rivers	Map. 1 where the flow is above Threshold.

Hydraulic Erosion

Pipe-model water erosion (rivers, gullies).

Inputs

Input	Kind	Default	Notes
In	Map, any width		The value this node works on.
Iterations	Whole number	120	How many steps the water runs for. More steps carve deeper channels but take longer. Slider from 1 to 400.
Time Step	Number	0.02	How much happens in each step. Bigger values work faster but can give noisy results. 0 does nothing. Slider from 0 to 0.2.
Rain	Number	0.012	Water added to every pixel in each step. More rain carves more ground. Slider from 0 to 1.
Evaporation	Number	0.015	How fast the water dries up. Higher values leave less water to carve. Slider from 0 to 0.5.
Sediment Capacity	Number	1	How much soil running water can carry. Higher values carve deeper channels. Slider from 0 to 4.
Erode Rate	Number	0.3	How fast the water picks up ground when it can carry more soil. Slider from 0 to 1.
Deposit Rate	Number	0.3	How fast the water drops the soil that it cannot carry. Slider from 0 to 1.
Min Tilt	Number	0.01	The lowest slope the water acts on, so it still erodes flat ground. Higher values erode flat areas more. Slider from 0 to 0.1.
Gravity	Number	9.81	How strongly water is pulled downhill. Higher values make it flow faster. Slider from 1 to 20.
Mask Depth	Number	2	Metres of change that count as a full Eroded or Deposited mask. Slider from 0.1 to 50.

Outputs

Output	Kind
Out	Map, any width. The result this node produces.
Eroded	Map. 1 where erosion removed at least Mask Depth metres of ground. Good for rock splats.
Deposited	Map. 1 where erosion left at least Mask Depth metres of sediment. Good for gravel and dirt splats.

Thermal Erosion

Slumps steep slopes toward a talus angle.

Inputs

Input	Kind	Default	Notes
In	Map, any width		The value this node works on.
Iterations	Whole number	60	How many times loose ground slides. More passes flatten slopes further but take longer. Slider from 1 to 400.
Talus	Number	0.008	The steepest slope that stays put, as the height step between neighboring pixels, 0 to 1 of the terrain height. Lower flattens more. Slider from 0 to 0.1.
Strength	Number	0.5	How much of the extra ground slides in each pass. 0 does nothing, 1 is the fastest. Slider from 0 to 1.
Mask Depth	Number	2	Metres of change that count as a full Eroded or Deposited mask. Slider from 0.1 to 50.

Outputs

Output	Kind
Out	Map, any width. The result this node produces.
Eroded	Map. 1 where erosion removed at least Mask Depth metres of ground. Good for rock splats.
Deposited	Map. 1 where erosion left at least Mask Depth metres of sediment. Good for gravel and dirt splats.