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Terrain Surface Gradient List Component

The Terrain Surface Gradient List component defines mappings between a gradient and a surface type on a terrain layer. When you assign a gradient to a surface, the gradient defines the strength of that surface in the displayed terrain. For example, you can assign a gradient to a rocky surface to make parts of it appear through a grassy region.

Usage

Terrain surface weight mappings control the strength of a surface type across the terrain surface. Multiple surface types and weights can exist at the same point. For example, a surface can be 30% grass, 50% dirt, and 20% rock. Other systems query these weights to determine how to render the terrain, what physics properties to apply to the terrain, and so on.

You select a gradient either by dragging an entity containing a gradient component to the GradientEntity field, or by clicking . Once a gradient is assigned, you can select the surface type that this gradient represents, by using the Surface Tag pull-down menu. You can configure the dimensions and priority of the layer using the required Terrain Layer Spawner.

More than one gradient to surface type mapping can be defined in this component. Each gradient needs to map to a different surface type. A simple example of multiple gradient mappings would be to have two surface types where one gradient is the inverse of the other. You can have more than two as well that can be blended together.

Provider

Terrain Gem

Dependencies

Terrain Layer Spawner

Properties

Terrain Surface Gradient List component properties

PropertyDescriptionValuesDefault
Gradient to Surface MappingsAn array of gradient entities and surface tags to map together.
GradientEntityThe gradient entity to assign to this layer.Gradient EntityNone
Surface TagSets the surface tag that this gradient represents.

See the adding surface tag names guide for creating your own surface tags.
Surface Tag(unassigned)

TerrainAreaSurfaceRequestBus

The TerrainAreaSurfaceRequestBus is an internal EBus used by the terrain system to query individual Terrain Surface Gradient List components. Other systems generally do not need to use this EBus since nothing outside the terrain system should need any information from the individual component instances. However, if a use case arises, the following request functions on the TerrainAreaSurfaceRequestBus EBus interface can be used to query the individual Terrain Surface Gradient List components.

Request NameDescriptionParameterReturnScriptable
GetSurfaceWeightsReturns all of the surfaces that are assigned to this component, along with the gradient’s weight value at a specific position.Position: Vector3Surface Weights: Surface Tag Weight ListNo
GetSurfaceWeightsFromListReturns all of the surfaces that are assigned to this component, along with the gradient’s weight value at a list of positions.Position: Vector3 ListSurface Weights: Surface Tag Weight List of ListsNo