Erosion Tools
The erosion tools are the Erosion group of the Sculpt tools in the Terrain Tools panel. They run a small simulation under the brush: Hydraulic Erosion lets water carry the ground away, and Thermal Erosion lets loose ground slide down steep slopes.
Use an erosion tool
- Open the Terrain Tools and click Sculpt.
- Open the tool list and pick Hydraulic Erosion or Thermal Erosion, in the Erosion group. The tool's settings show under the tool list.
- Hold Mouse Left and drag over the terrain. The simulation runs at each stamp, and the ground changes under the brush.
Each stroke is one undo step: Ctrl+Z undoes it. Both tools use the brush, the Stroke settings and the Filters of the panel.
The settings of both tools go back to their defaults when RustEdit starts again.
Hydraulic Erosion
Simulates water that carries ground away and drops it lower down. Hold Ctrl while you paint to turn the effect around.
The tool's section shows the simulation settings. The first rows control the whole simulation:
| Option | What it does |
|---|---|
| Simulation Scale | The world scale of the simulation. From 0 to 100. The default is 1. |
| Time Interval (dt) | The time step of each iteration. A smaller value is more accurate, but has less effect unless you add more iterations. From 0 to 0.1. The default is 0.05. |
| Iterations | How many steps of the simulation run for each stamp. More steps give a stronger result, but take longer. From 1 to 500. The default is 100. |
| Iteration Blend Scalar | How much of each step goes into the result. From -1 to 1. The default is 1. |
Thermal Smoothing
The Thermal Smoothing group lets loose ground settle after the water moves it:
| Option | What it does |
|---|---|
| Thermal Erosion | Turns thermal smoothing on or off. It is on by default. |
| Time Scalar | How strong the thermal smoothing is. From 0.0001 to 10. The default is 0.005. |
| Iterations | How many smoothing steps run for each step of the water. From 1 to 100. The default is 3. |
| Resting Angle | The steepest slope, in degrees, that loose ground stays on. From 0 to 90. The default is 85. |
Water Transport
The Water Transport group controls the water:
| Option | What it does |
|---|---|
| Water Level Scale | A multiplier for the water level. From 0 to 1. The default is 1. |
| Precipitation Rate | How fast water is added. A higher value gives water more effect, but a value that is too high can make the simulation unstable. From 0 to 10. The default is 0.4. |
| Evaporation Rate | How fast water is removed. A higher value gives water less effect. From 0 to 10. The default is 0.4. |
| Flow Rate | How fast water flows over the ground. A higher value erodes more, but a value that is too high can make the simulation unstable. From 0 to 10. The default is 0.4. |
Sediment Transport
The Sediment Transport group controls the ground that the water carries (sediment):
| Option | What it does |
|---|---|
| Sediment Scale | A multiplier for the sediment. From 0 to 1. The default is 1. |
| Sediment Capacity | The most sediment that the water can carry. From 0 to 10. The default is 0.42. |
| Sediment Deposit Rate | How fast the water drops sediment back onto the ground. From 0 to 10. The default is 0.4. |
| Sediment Dissolution Rate | How fast the water picks up ground as sediment. From 0 to 10. The default is 0.51. |
Riverbank
The Riverbank group sets multipliers for steep and flat ground. The riverbank rows apply where the slope is almost vertical. The riverbed rows apply where the ground is almost flat. Each row goes from 0 to 10.
| Option | Default |
|---|---|
| Riverbank Deposit Rate | 8 |
| Riverbank Dissolution Rate | 2 |
| Riverbed Deposit Rate | 2 |
| Riverbed Dissolution Rate | 8 |
Thermal Erosion
Simulates weathering: rock crumbles and the loose ground settles down the slope.
| Option | What it does |
|---|---|
| Physical Material Presets | Ready-made resting angles for real materials, for example Dry Sand, Gravel or Snow. Picking one sets Resting Angle. The default is Dry Sand. If you change Resting Angle yourself, this row changes to Custom. |
| Iterations | How many steps of the simulation run for each stamp. From 1 to 1000. The default is 50. |
| Time Interval (dt) | The time step of each iteration. A smaller value is more accurate, but has less effect unless you add more iterations. From 0.00001 to 0.05. The default is 0.0025. |
| Resting Angle | The range of slopes, in degrees, that loose ground settles at. From 0 to 90. The default is 32 to 36. |
| Resting Angle Jitter | Adds a random change to the resting angle for each stamp, in degrees. From 0 to 90. The default is 0. |