记录游戏执行加载事件的时间很重要，原因有二：
- 避免加载时污染帧时间数据。
- 分析加载时间，查看何时何地加载时间超过可接受的范围。
加载事件可以关联元数据
public class LoadingTimeMetadata
{
public enum LoadingState
{
Unknown = 0,
/// <summary>
/// The first time the game is run.
/// </summary>
FirstRun = 1,
/// <summary>
/// App is not backgrounded.
/// </summary>
ColdStart = 2,
/// <summary>
/// App is backgrounded.
/// </summary>
WarmStart = 3,
/// <summary>
/// App is backgrounded, least work needed.
/// </summary>
HotStart = 4,
/// <summary>
/// Asset loading between levels.
/// </summary>
InterLevel = 5
}
public LoadingState state;
public enum LoadingSource
{
UnknownSource = 0,
/// <summary>
/// Uncompressing data.
/// </summary>
Memory = 1,
/// <summary>
/// Reading assets from APK bundle.
/// </summary>
Apk = 2,
/// <summary>
/// Reading assets from device storage.
/// </summary>
DeviceStorage = 3,
/// <summary>
/// Reading assets from external storage, e.g. SD card.
/// </summary>
ExternalStorage = 4,
/// <summary>
/// Loading assets from the network.
/// </summary>
Network = 5,
/// <summary>
/// Shader compilation.
/// </summary>
ShaderCompilation = 6,
/// <summary>
/// Time spent between process starting and onCreate.
/// </summary>
PreActivity = 7,
/// <summary>
/// Total time spent between process starting and first render frame.
/// </summary>
FirstTouchToFirstFrame = 8,
/// <summary>
/// Time from start to end of a group of events.
/// </summary>
TotalUserWaitForGroup = 9
}
public LoadingSource source;
/// <summary>
/// 0 = no compression, 100 = max compression
/// </summary>
public int compression_level;
public enum NetworkConnectivity
{
Unknown = 0,
Wifi = 1,
CellularNetwork = 2
}
public NetworkConnectivity network_connectivity;
/// <summary>
/// Bandwidth in bits per second.
/// </summary>
public ulong network_transfer_speed_bps;
/// <summary>
/// Latency in nanoseconds.
/// </summary>
public ulong network_latency_ns;
}
任何与您的需求无关的字段都可以设置为零。
加载事件还可以关联一个注解。您可以使用 Annotation 消息中的一个或多个字段，以与帧时间注解相同的方式进行定义。
Result<ulong> StartRecordingLoadingTime(LoadingTimeMetadata eventMetadata, TAnnotation annotation);
此函数开始记录与给定元数据和注解关联的加载时间事件，并填充一个 Result<ulong>.value，用于 StopRecordingLoadingTime() 函数。
ErrorCode StopRecordingLoadingTime(ulong handle);
此函数停止记录之前由 StartRecordingLoadingTime() 启动的事件。该事件将在下一次会话刷新时上传。
加载组函数
在您的游戏中，您可能会为用户看到的单个加载周期记录多个加载事件。一些示例包括文件加载、场景加载、解压缩和着色器编译。
务必告知 Android Performance Tuner 这些加载事件属于某个组，以便它提供更好的洞察。为此，请使用以下启动和停止函数将您的加载事件括起来。
Result<ulong> StartLoadingGroup(LoadingTimeMetadata eventMetadata, TAnnotation annotation);
此函数启动一个与给定元数据和注解关联的加载组，并填充一个 Result<ulong>.value，用于 StopLoadingGroup() 函数。目前 Play 后端不使用元数据和注解，但注解可以设置为 null。所有后续加载事件都将通过唯一的组 ID 进行标记。
ErrorCode StopLoadingGroup(ulong handle);
此函数停止之前由 StartLoadingGroup() 启动的加载组。在再次调用 StartLoadingGroup() 之前，后续加载事件将没有组 ID。
图 1. 加载组示例。
示例
以下是一些如何在游戏中添加加载时间函数的示例。
文件加载事件
以下代码示例展示了如何在您的游戏中记录文件加载事件。
public RawImage image;
IEnumerator LoadImageFromStreamingAssets(string imageName)
{
string imagePath = "file://" + Path.Combine(Application.streamingAssetsPath, imageName);
using (var r = UnityWebRequestTexture.GetTexture(imagePath))
{
LoadingTimeMetadata fileLoadingMetadata = new LoadingTimeMetadata()
{
state = LoadingTimeMetadata.LoadingState.InterLevel,
source = LoadingTimeMetadata.LoadingSource.DeviceStorage,
// Fields are zero by default but they could be set as follows
compression_level = 0,
network_connectivity = 0,
network_transfer_speed_bps = 0,
network_latency_ns = 0
};
Annotation annotation = new Annotation()
{
Scene = Scene.MagicalForest
};
// Start recording loading time.
Result<ulong> result = performanceTuner.StartRecordingLoadingTime(fileLoadingMetadata, annotation);
yield return r.SendWebRequest();
// Stop recording loading time.
performanceTuner.StopRecordingLoadingTime(result.value);
if (r.isNetworkError || r.isHttpError)
{
Debug.Log(r.error);
}
else
{
Texture2D tex = DownloadHandlerTexture.GetContent(r);
image.texture = tex;
}
}
}
场景加载事件
以下代码示例展示了如何在您的游戏中记录场景加载事件。
IEnumerator LoadScene(int sceneIndex)
{
LoadingTimeMetadata metadata = new LoadingTimeMetadata()
{state = LoadingTimeMetadata.LoadingState.InterLevel};
Annotation annotation = new Annotation() {Scene = (Scene) (sceneIndex + 1)};
Result<ulong> result = performanceTuner.StartRecordingLoadingTime(metadata, annotation);
AsyncOperation asyncSceneLoad = SceneManager.LoadSceneAsync(sceneIndex, LoadSceneMode.Single);
while (!asyncSceneLoad.isDone)
{
yield return null;
}
performanceTuner.StopRecordingLoadingTime(result.value);
}
加载组函数
以下代码示例展示了如何向您的游戏添加加载组函数。
IEnumerator LoadImages()
{
LoadingTimeMetadata groupMetadata = new LoadingTimeMetadata()
{
state = LoadingTimeMetadata.LoadingState.InterLevel,
source = LoadingTimeMetadata.LoadingSource.DeviceStorage,
};
Result<ulong> result = performanceTuner.StartLoadingGroup(groupMetadata, null);
yield return StartCoroutine(LoadImageFromStreamingAssets("image1.jpeg"));
yield return StartCoroutine(LoadImageFromStreamingAssets("image2.jpeg"));
yield return StartCoroutine(LoadImageFromStreamingAssets("image3.jpeg"));
yield return StartCoroutine(LoadImageFromStreamingAssets("image4.jpeg"));
var stopErrorCode = performanceTuner.StopLoadingGroup(0);
}