Library/PackageCache/com.unity.postprocessing@2.1.2/PostProcessing/Runtime/Monitors/WaveformMonitor.cs

   1 using System;
   2
   3 namespace UnityEngine.Rendering.PostProcessing
   4 {
   5     /// <summary>
   6     /// This class holds settings for the Waveform monitor.
   7     /// </summary>
   8     [Serializable]
   9     public sealed class WaveformMonitor : Monitor
  10     {
  11         /// <summary>
  12         /// The exposure multiplier applied to the waveform values.
  13         /// </summary>
  14         public float exposure = 0.12f;
  15
  16         /// <summary>
  17         /// The height of the rendered waveform.
  18         /// </summary>
  19         /// <remarks>
  20         /// Waveforms display localized values so the width is dynamic and depends on the current
  21         /// aspect ratio.
  22         /// </remarks>
  23         public int height = 256;
  24
  25         ComputeBuffer m_Data;
  26
  27         const int k_ThreadGroupSize = 256;
  28         const int k_ThreadGroupSizeX = 16;
  29         const int k_ThreadGroupSizeY = 16;
  30
  31         internal override void OnDisable()
  32         {
  33             base.OnDisable();
  34
  35             if (m_Data != null)
  36                 m_Data.Release();
  37
  38             m_Data = null;
  39         }
  40
  41         internal override bool NeedsHalfRes()
  42         {
  43             return true;
  44         }
  45
  46
  47         internal override bool ShaderResourcesAvailable(PostProcessRenderContext context)
  48         {
  49             return context.resources.computeShaders.waveform;
  50         }
  51
  52         internal override void Render(PostProcessRenderContext context)
  53         {
  54             // Waveform show localized data, so width depends on the aspect ratio
  55             float ratio = (context.width / 2f) / (context.height / 2f);
  56             int width = Mathf.FloorToInt(height * ratio);
  57
  58             CheckOutput(width, height);
  59             exposure = Mathf.Max(0f, exposure);
  60
  61             int count = width * height;
  62             if (m_Data == null)
  63             {
  64                 m_Data = new ComputeBuffer(count, sizeof(uint) << 2);
  65             }
  66             else if (m_Data.count < count)
  67             {
  68                 m_Data.Release();
  69                 m_Data = new ComputeBuffer(count, sizeof(uint) << 2);
  70             }
  71
  72             var compute = context.resources.computeShaders.waveform;
  73             var cmd = context.command;
  74             cmd.BeginSample("Waveform");
  75
  76             var parameters = new Vector4(
  77                 width,
  78                 height,
  79                 RuntimeUtilities.isLinearColorSpace ? 1 : 0,
  80                 0f
  81             );
  82
  83             // Clear the buffer on every frame
  84             int kernel = compute.FindKernel("KWaveformClear");
  85             cmd.SetComputeBufferParam(compute, kernel, "_WaveformBuffer", m_Data);
  86             cmd.SetComputeVectorParam(compute, "_Params", parameters);
  87             cmd.DispatchCompute(compute, kernel, Mathf.CeilToInt(width / (float)k_ThreadGroupSizeX), Mathf.CeilToInt(height / (float)k_ThreadGroupSizeY), 1);
  88
  89             // For performance reasons, especially on consoles, we'll just downscale the source
  90             // again to reduce VMEM stalls. Eventually the whole algorithm needs to be rewritten as
  91             // it's currently pretty naive.
  92             cmd.GetTemporaryRT(ShaderIDs.WaveformSource, width, height, 0, FilterMode.Bilinear, context.sourceFormat);
  93             cmd.BlitFullscreenTriangle(ShaderIDs.HalfResFinalCopy, ShaderIDs.WaveformSource);
  94
  95             // Gather all pixels and fill in our waveform
  96             kernel = compute.FindKernel("KWaveformGather");
  97             cmd.SetComputeBufferParam(compute, kernel, "_WaveformBuffer", m_Data);
  98             cmd.SetComputeTextureParam(compute, kernel, "_Source", ShaderIDs.WaveformSource);
  99             cmd.SetComputeVectorParam(compute, "_Params", parameters);
 100             cmd.DispatchCompute(compute, kernel, width, Mathf.CeilToInt(height / (float)k_ThreadGroupSize), 1);
 101             cmd.ReleaseTemporaryRT(ShaderIDs.WaveformSource);
 102
 103             // Generate the waveform texture
 104             var sheet = context.propertySheets.Get(context.resources.shaders.waveform);
 105             sheet.properties.SetVector(ShaderIDs.Params, new Vector4(width, height, exposure, 0f));
 106             sheet.properties.SetBuffer(ShaderIDs.WaveformBuffer, m_Data);
 107             cmd.BlitFullscreenTriangle(BuiltinRenderTextureType.None, output, sheet, 0);
 108
 109             cmd.EndSample("Waveform");
 110         }
 111     }
 112 }