Files
FlaxEngine/Source/Editor/Viewport/Previews/AudioClipPreview.cs
2023-10-12 14:31:41 +02:00

301 lines
11 KiB
C#

// Copyright (c) 2012-2023 Wojciech Figat. All rights reserved.
using System;
using System.Threading.Tasks;
using FlaxEngine;
using FlaxEngine.GUI;
namespace FlaxEditor.Viewport.Previews
{
/// <summary>
/// Audio clip PCM data editor preview.
/// </summary>
/// <seealso cref="FlaxEngine.GUI.ContainerControl" />
[HideInEditor]
public class AudioClipPreview : ContainerControl
{
/// <summary>
/// The audio clip drawing modes.
/// </summary>
public enum DrawModes
{
/// <summary>
/// Fills the whole control area with the full clip duration.
/// </summary>
Fill,
/// <summary>
/// Draws single audio clip. Uses the view scale parameter.
/// </summary>
Single,
/// <summary>
/// Draws the looped audio clip. Uses the view scale parameter.
/// </summary>
Looped,
};
private readonly object _locker = new object();
private AudioClip _asset;
private int _pcmSequence = 0;
private float[] _pcmData;
private AudioDataInfo _pcmInfo;
/// <summary>
/// Gets or sets the clip to preview.
/// </summary>
public AudioClip Asset
{
get => _asset;
set
{
lock (_locker)
{
if (_asset == value)
return;
_asset = value;
_pcmData = null;
if (_asset)
{
// Use async task to gather PCM data (engine loads it from the asset)
Task.Run(DownloadData);
}
}
}
}
/// <summary>
/// Gets a value indicating whether audio data has been fetched from the asset (done as an async task). It is required to be valid in order to draw the audio buffer preview.
/// </summary>
public bool HasData
{
get
{
lock (_locker)
{
return _pcmData != null;
}
}
}
/// <summary>
/// Gets the cached audio data info.
/// </summary>
public AudioDataInfo DataInfo
{
get
{
lock (_locker)
{
return _pcmInfo;
}
}
}
/// <summary>
/// The draw mode.
/// </summary>
public DrawModes DrawMode = DrawModes.Fill;
/// <summary>
/// The view offset parameter. Shifts the audio preview (in seconds).
/// </summary>
public float ViewOffset = 0.0f;
/// <summary>
/// The view scale parameter. Increase it to zoom in the audio. Usage depends on the current <see cref="DrawMode"/>.
/// </summary>
public float ViewScale = 1.0f;
/// <summary>
/// The color of the audio PCM data spectrum.
/// </summary>
public Color Color = Color.White;
/// <summary>
/// The audio units per second (on time axis).
/// </summary>
public static readonly float UnitsPerSecond = 100.0f;
/// <summary>
/// Invalidates the cached audio PCM data and fetches it again from the asset.
/// </summary>
public void RefreshPreview()
{
lock (_locker)
{
if (_asset != null)
{
// Release any cached data
_pcmData = null;
// Invalidate any in-flight data download to reject cached data due to refresh
if (_pcmSequence != 0)
_pcmSequence++;
// Use async task to gather PCM data (engine loads it from the asset)
Task.Run(DownloadData);
}
}
}
/// <inheritdoc />
public override void Draw()
{
base.Draw();
lock (_locker)
{
var info = _pcmInfo;
if (_asset == null || _pcmData == null || info.NumSamples == 0)
return;
var height = Height;
var width = Width;
var samplesPerChannel = info.NumSamples / info.NumChannels;
var length = (float)samplesPerChannel / info.SampleRate;
var color = Color;
if (!EnabledInHierarchy)
color *= 0.4f;
var sampleValueScale = height / info.NumChannels;
// Calculate the amount of samples that are contained in the view
float unitsPerSecond = UnitsPerSecond * ViewScale;
float clipDefaultWidth = length * unitsPerSecond;
float clipsInView = width / clipDefaultWidth;
float clipWidth;
uint samplesPerIndex;
switch (DrawMode)
{
case DrawModes.Fill:
clipsInView = 1.0f;
clipWidth = width;
samplesPerIndex = (uint)(samplesPerChannel / width) * info.NumChannels;
break;
case DrawModes.Single:
clipsInView = Mathf.Min(clipsInView, 1.0f);
clipWidth = clipDefaultWidth;
samplesPerIndex = (uint)(info.SampleRate / unitsPerSecond) * info.NumChannels;
break;
case DrawModes.Looped:
clipWidth = width / clipsInView;
samplesPerIndex = (uint)(info.SampleRate / unitsPerSecond) * info.NumChannels;
break;
default: throw new ArgumentOutOfRangeException();
}
const uint maxSamplesPerIndex = 64;
uint samplesPerIndexDiff = Math.Max(1, samplesPerIndex / Math.Min(samplesPerIndex, maxSamplesPerIndex));
// Calculate the clip range in the view to optimize drawing (eg. if only part fo the clip is visible)
Render2D.PeekClip(out var globalClipping);
Render2D.PeekTransform(out var globalTransform);
var globalRect = new Rectangle(globalTransform.M31, globalTransform.M32, width * globalTransform.M11, height * globalTransform.M22);
var globalMask = Rectangle.Shared(globalClipping, globalRect);
var globalTransformInv = Matrix3x3.Invert(globalTransform);
var localRect = Rectangle.FromPoints(Matrix3x3.Transform2D(globalMask.UpperLeft, globalTransformInv), Matrix3x3.Transform2D(globalMask.BottomRight, globalTransformInv));
var localRectMin = localRect.UpperLeft;
var localRectMax = localRect.BottomRight;
// Render each clip separately
var viewOffset = (uint)(info.SampleRate * info.NumChannels * ViewOffset);
for (uint clipIndex = 0; clipIndex < Mathf.CeilToInt(clipsInView); clipIndex++)
{
var clipStart = clipWidth * clipIndex;
var clipEnd = clipStart + clipWidth;
var xStart = Mathf.Max(clipStart, localRectMin.X);
var xEnd = Mathf.Min(Mathf.Min(width, clipEnd), localRectMax.X);
var samplesOffset = (uint)((xStart - clipStart) * samplesPerIndex) + viewOffset;
// Render every audio channel separately
for (uint channelIndex = 0; channelIndex < info.NumChannels; channelIndex++)
{
uint currentSample = channelIndex + samplesOffset;
float yCenter = Y + ((2 * channelIndex) + 1) * height / (2.0f * info.NumChannels);
for (float pixelX = xStart; pixelX < xEnd; pixelX++)
{
float samplesSum = 0;
int samplesInPixel = 0;
uint samplesEnd = Math.Min(currentSample + samplesPerIndex, info.NumSamples);
for (uint sampleIndex = currentSample; sampleIndex < samplesEnd; sampleIndex += samplesPerIndexDiff)
{
samplesSum += Mathf.Abs(_pcmData[sampleIndex]);
samplesInPixel++;
}
currentSample = samplesEnd;
if (samplesInPixel > 0)
{
float sampleValueAvg = samplesSum / samplesInPixel;
float sampleValueAvgScaled = sampleValueAvg * sampleValueScale;
if (sampleValueAvgScaled > 0.1f)
{
Render2D.DrawLine(new Float2(pixelX, yCenter - sampleValueAvgScaled), new Float2(pixelX, yCenter + sampleValueAvgScaled), color);
}
}
}
}
}
}
}
/// <inheritdoc />
public override void OnDestroy()
{
lock (_locker)
{
_asset = null;
_pcmData = null;
}
base.OnDestroy();
}
/// <summary>
/// Downloads the audio clip raw PCM data. Use it from async thread to prevent blocking,
/// </summary>
private void DownloadData()
{
AudioClip asset;
int sequence;
lock (_locker)
{
asset = _asset;
sequence = _pcmSequence;
}
if (!asset)
return;
float[] data;
AudioDataInfo dataInfo;
try
{
asset.ExtractDataFloat(out data, out dataInfo);
}
catch (Exception ex)
{
Editor.LogWarning("Failed to get audio clip PCM data. " + ex.Message);
Editor.LogWarning(ex);
return;
}
if (data.Length != dataInfo.NumSamples)
{
Editor.LogWarning("Failed to get audio clip PCM data. Invalid samples count. Returned buffer has other size.");
}
lock (_locker)
{
// If asset has been modified during data fetching, ignore it
if (_asset == asset && _pcmSequence == sequence)
{
_pcmSequence++;
_pcmData = data;
_pcmInfo = dataInfo;
}
}
}
}
}