enhance(Audio): 一時停止機能を追加

Promete.Example/examples/audio/ogg_vorbis.cs

@@ -25,6 +25,8 @@ public override void OnUpdate()
 		               Location: {audio.Time / 1000f:0.000} / {audio.Length / 1000f:0.000}
 		               Location in Samples: {audio.TimeInSamples} / {audio.LengthInSamples}
 		               Loaded: {bgm.LoadedSize} / {bgm.Samples}
+		               Is Playing: {audio.IsPlaying}
+		               Is Pausing: {audio.IsPausing}
 		               [↑] Volume Up
 		               [↓] Volume Down
 		               [←] Pitch Down
@@ -49,9 +51,13 @@ PRESS ESC TO RETURN
 
 		if (keyboard.Space.IsKeyDown)
 		{
-			if (audio.IsPlaying)
+			if (audio is { IsPlaying: true, IsPausing: false })
 			{
-				audio.Stop();
+				audio.Pause();
+			}
+			else if (audio.IsPausing)
+			{
+				audio.Resume();
 			}
 			else
 			{

Promete/Audio/AudioPlayer.cs

@@ -133,6 +133,25 @@ public async void Play(IAudioSource source, int? loop = default)
 		await PlayAsync(source, loop, stopToken);
 	}
 
+	/// <summary>
+	/// 一時停止します。
+	/// </summary>
+	public void Pause()
+	{
+		if (!IsPlaying) return;
+		IsPausing = true;
+	}
+
+	/// <summary>
+	/// 一時停止を解除します。
+	/// </summary>
+	public void Resume()
+	{
+		if (!IsPausing) return;
+		IsPausing = false;
+		Console.WriteLine("set IsPausing to false");
+	}
+
 	/// <summary>
 	/// 再生を停止します。
 	/// </summary>
@@ -277,6 +296,16 @@ private async ValueTask PlayAsync(IAudioSource source, int? loop, StopTokenSourc
 
 			await Task.Delay(1).ConfigureAwait(false);
 
+			if (IsPausing)
+			{
+				al.SourcePause(alSource.Handle);
+				while (IsPausing)
+				{
+					await Task.Delay(1).ConfigureAwait(false);
+				}
+				al.SourcePlay(alSource.Handle);
+			}
+
 			// 外部から再生停止が要求された場合、再生を終了する
 			if (st.IsStopRequested)
 			{