Priority of background loading thread.
Lets you control how long it takes to load data asynchronously vs performance impact on the game while loading in the background.
Asynchronous load functions that load objects (Resources.LoadAsync, AssetBundle.LoadAssetAsync, AssetBundle.LoadAllAssetAsync), scenes (SceneManager.LoadSceneAsync) do data read and deserealization on a separate background loading thread and object integration on a main thread.
Integration depends on an object type and for textures, meshes means uploading data to the GPU, audio clips prepare data for playing.
To avoid hiccups we limit integration time on a main thread depending on backgroundLoadingPriority value:
- ThreadPriority.Low - 2ms;
- ThreadPriority.BelowNormal - 4ms;
- ThreadPriority.Normal - 10ms;
- ThreadPriority.High - 50ms.
This is a maximum time all asynchronous operations can spend within a single frame on a main thread.
Background loading thread uses backgroundLoadingPriority directly.
// Load as much data as possible, as a result frame rate will drop. // Good for fast loading when showing progress bars. Application.backgroundLoadingPriority = ThreadPriority.High;
// Load data very slowly and try not to affect performance of the game. // Good for loading in the background while the game is playing. Application.backgroundLoadingPriority = ThreadPriority.Low;
using UnityEngine; using System.Collections;
public class ExampleClass : MonoBehaviour { void Example() { Application.backgroundLoadingPriority = ThreadPriority.High; Application.backgroundLoadingPriority = ThreadPriority.Low; } }
See Also: ThreadPriority enum, AsyncOperation.priority.