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Overview
The Wide Flows Erosion filter offers a highly adjustable particle-based erosion and thinking of it as a simulation running many individual droplets is key to understanding all of its properties.
The filter simulates a water droplet with a set amount of water that influences its carrying capacity and ability to erode the terrain. The droplet moves downwards at a constant rate, eroding and depositing sediment in its path.
TABLE OF CONTENTS
Parameters
- Seed
Changes the seed for the rain droplet distribution and other parameters used in the simulation.
- Rain Strength
This lets you adjust the amount of droplets spawned on the terrain. You can also further modify the rain strengths on each level step in the level step editor below the slider.
The level step that a droplet runs on heavily impacts the structures the filter will produce. Lower levels generate wider crevices and sedimentation, while higher levels create more intricate details.
- Step Size
The distance a droplet can travel per iteration.
- Inertia
Controls how fast a droplet will react to a changing direction. A higher Inertia means it will stay for longer on its previous path even if the downward direction changes.
- River Forming
This favors droplets to take the same paths as previous droplets passing through the same area.
- Sediment Loss
This describes a constant percentage of sediment that a droplet will lose in every movement step it takes.
- Smooth Normals
Switches to an alternate movement computation. Can be used to achieve slightly smoother trails in some scenarios.
- Erosion Strength
Controls how much sediment a droplet can erode.
- Initial Water
Sets the amount of water a droplet has when it is spawned. The water influences its maximum lifetime and the amount of sediment it can carry.
- Max Length
Sets the maximum travel length of a droplet in pixels.
- Transport Rate
Modifies the amount of sediment a droplet can carry.
- Erosion Multiplier
A factor that affects the final amount of sediment eroded from the terrain. Any other value than 1 can disturb the equilibrium of the filter and add/remove matter from the terrain.
- Deposition Multiplier
A factor that affects the final amount of sediment deposited onto the terrain. Any other value than 1 can disturb the equilibrium of the filter and add/remove matter from the terrain.
- Evaporation
How much water is lost at each stage of a droplet's journey.
- Delta
Allows you to scale the movement speed of the particles in the simulation.
- Flow Rotation
Alters the starting direction of a particle.
- Random Rotation
Normally, a droplet will have a downslope path when spawned. Increasing this value will randomize it.
- Wind Direction
Allows you to set a wind direction, which will influence a particle's movement direction.
- Wind Strength
Controls how strongly droplets will be affected by the wind.
Results
 base erosion |  softer base erosion |
 rough sedimentation |  strong rough erosion |
 strong streams |  soft streams |
 strong erosion |  strong soft erosion |