Awesome
Terrain Layer Sampler for Unity
Scripting functionality to efficiently read terrain layer weights in realtime.
Motivations
The painted strength of a terrain layer is stored in a channel of an RGBA splatmap texture. Reading this back using Texture2D.GetPixel is too slow for realtime uses.
Instead this script can pre-bake this information into a ScriptableObject, and provides an API for sampling the data at any given world-space position. The weight/strength for each terrain layer is returned as an array.
- Sampling is performed using bi-linear interpolation, providing smoothly interpolated data between splatmap texels.
- Data is automatically updated for areas that are modified through terrain texture painting. This ensures fast updates and retains common workflows.
Example use cases
- Controlling particle effects for feet and/or wheels.
- Driving audio events or parameters.
- Deriving physics properties from the terrain surface (eg. checking if the ground is icy or wet).
- Prefab spawning, based on textures.
Adding it to a project
via Package Manager:
- Press the "+" icon in the top-left
- Choose "Add package from git URL"
- Paste in
https://github.com/staggartcreations/UnityTerrainLayerSampler.git
.
via Git:
- Clone the repo as usual via cmd/terminal or in your favourite Git GUI software.
- Checkout the 'master' branch
via browser
- Click the green "Code" button at the top of the page, and choose "Download ZIP"
- Extract the folder to your Assets folder
Usage instructions
- Add the
TerrainLayerComponent
to your terrain(s)
A TerrainLayerData
asset will automatically be created, and will be saved on the component with the scene. You can however choose to use a ScriptableObject that is saved on disk. In order to do so, right-click in the Project window and choose Create/TerrainLayerData
and assign it. The context menu on the component has a "Bake" option.
- See the
Example/TerrainLayerSampler
script for further practical details.
Scripting Workflow
- Find a reference to the terrain you are on (either through Raycasting, or a custom look-up method). This is likely needed anyway (eg. checking if feet are grounded).
- Once found, the
TerrainLayerComponent
can be fetched through GetComponent, and itsdata
field can be accessed. - Finally, the
data.Sample(Vector3 position, bool interpolated)
function can be called, which returns afloat[]
array. Each array element corresponds to a layer on the terrain (in the same order as they are added to it). The float values represent the strength a layer at the given position (always between 0 and 1).