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Version: 21 Aug 2024

MLAudioPlayback.cs

Source code

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR.MagicLeap.Native;

namespace UnityEngine.XR.MagicLeap
{
public partial class MLAudioPlayback
{
protected static MLAudioPlayback Instance
{
get
{
if (instance == null)
{
instance = new MLAudioPlayback();
MLThreadDispatch.ScheduleMain(() => instance.outputSampleRate = (uint)AudioSettings.outputSampleRate);
}

return instance;
}
}

private static MLAudioPlayback instance;

// MLAudioOutput plugin converts the buffer of floats into a buffer of shorts
private const uint OutputSampleSize = sizeof(short);
private const uint BitsPerOutputSample = OutputSampleSize * 8;
private const float MaxOutputPitch = 1.0f;
private const uint DefaultCacheDurationInSeconds = 4;

private uint cacheDurationInSeconds;
private uint outputBufferSizeInBytes;
private uint outputSampleRate;
private uint outputChannels;
private bool isStarted;
private bool bufferCreated;

public static void CreateAudioBuffer() => Instance.CreateAudioBufferInternal(DefaultCacheDurationInSeconds);

public static void CreateAudioBuffer(uint cacheDurationInSeconds) => Instance.CreateAudioBufferInternal(cacheDurationInSeconds);

public static void DestroyAudioBuffer() => Instance.DestroyAudioBufferInternal();

public static void SubmitBuffer(float[] data, int channels) => Instance.SubmitBufferInternal(data, channels);

private void CreateAudioBufferInternal(uint cacheDurationInSeconds)
{
if (!isStarted)
{
#if UNITY_EDITOR
this.cacheDurationInSeconds = cacheDurationInSeconds;
NativeBindings.CreateAudioOutput();
this.bufferCreated = false;
this.isStarted = true;
#endif
}
}

private void DestroyAudioBufferInternal()
{
#if UNITY_EDITOR
NativeBindings.DestroyAudioOutput();
isStarted = false;
#endif
}

private void SubmitBufferInternal(float[] data, int channels)
{
#if UNITY_EDITOR
if (!this.isStarted)
{
return;
}

// Prevent re-allocations in case this func gets called multiple
// times before MLAudioPlayback.CreateAudioBuffer().
if (!bufferCreated)
{
this.outputChannels = (uint)channels;
this.outputBufferSizeInBytes = ((uint)data.Length * OutputSampleSize);
NativeBindings.CreateOutputBuffer(this.outputBufferSizeInBytes, this.outputChannels, this.outputSampleRate, BitsPerOutputSample, BitsPerOutputSample, MaxOutputPitch, this.cacheDurationInSeconds);
bufferCreated = true;
}

NativeBindings.OnUnityAudio(data, (uint)data.Length);

#if UNITY_EDITOR
if (MagicLeapXrProvider.IsZIRunning)
{
#endif
// Mutes the audio that will be submitted to the engine for playback via FMOD.
for (int i = 0; i < data.Length; ++i)
data[i] = 0;
#if UNITY_EDITOR
}
#endif
#endif
}

}
}