PKFxAudioSourceSampler

using AOT;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using UnityEngine;

[RequireComponent(typeof(AudioSource))]
public class PKFxAudioSourceSampler : MonoBehaviour
{
    public string channel;

    private static Dictionary<string, AudioSource> m_AudioSources = new Dictionary<string, AudioSource>();
    private static float[] m_Samples;
    private static GCHandle m_SamplesHandle;
    private bool tmp;

    void Start()
    {
        // Initialize the data buffer. Expected size is 1024.
        m_Samples = new float[1024];
        // Pin the array
        m_SamplesHandle = GCHandle.Alloc(m_Samples, GCHandleType.Pinned);
        tmp = false;
        string key = channel;
        if (string.IsNullOrEmpty(key))
            key = "Master";
        m_AudioSources.Add(key, GetComponent<AudioSource>());
    }

    void Update()
    {
        if (!tmp)
        {
            AudioSource audioSrc = null;
            if (m_AudioSources.TryGetValue(channel, out audioSrc))
            {
                PKFxManager.SetDelegateOnAudioSpectrumData(Marshal.GetFunctionPointerForDelegate(new Func<IntPtr, IntPtr, IntPtr>(OnAudioSpectrumData)));
                PKFxManager.SetDelegateOnAudioWaveformData(Marshal.GetFunctionPointerForDelegate(new Func<IntPtr, IntPtr, IntPtr>(OnAudioWaveformData)));
            }
            tmp = true;
        }
    }

    // MonoPInvokeCallback is required by IL2CPP (mostly for iOS' static libs)
    [MonoPInvokeCallback(typeof(PKFxManager.AudioCallback))]
    public static IntPtr OnAudioSpectrumData(IntPtr channelName, IntPtr nbSamples)
    {
        string name = Marshal.PtrToStringAnsi(channelName);
        Debug.Log(name);
        AudioSource audioSrc = null;
        if (m_AudioSources.TryGetValue(name, out audioSrc))
        {
            audioSrc.GetSpectrumData(m_Samples, 0, FFTWindow.Rectangular);
            // Last value filled by Unity seems wrong...
            m_Samples[1023] = m_Samples[1022];
            // return the address of the pinned object.
            return m_SamplesHandle.AddrOfPinnedObject();
        }
        return IntPtr.Zero;
    }

    [MonoPInvokeCallback(typeof(PKFxManager.AudioCallback))]
    public static IntPtr OnAudioWaveformData(IntPtr channelName, IntPtr nbSamples)
    {
        string name = Marshal.PtrToStringAnsi(channelName);
        Debug.Log(name);
        AudioSource audioSrc = null;
        if (m_AudioSources.TryGetValue(name, out audioSrc))
        {
            audioSrc.GetOutputData(m_Samples, 0);
            // return the address of the pinned object.
            return m_SamplesHandle.AddrOfPinnedObject();
        }
        return IntPtr.Zero;
    }

    void OnDestroy()
    {
        // Unpin the object to allow GC.
        m_SamplesHandle.Free();
    }
}