Filter graph merging to convolutions

Cavern/Filters/Utilities/FilterGraphNodeUtils.cs

@@ -1,10 +1,33 @@
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Cavern.Filters.Utilities {
     /// <summary>
     /// Special functions for handling <see cref="FilterGraphNode"/>s.
     /// </summary>
     public static class FilterGraphNodeUtils {
+        /// <summary>
+        /// Convert the filter graph's filters to convolutions, and merge chains together to a single filter.
+        /// </summary>
+        public static void ConvertToConvolution(IEnumerable<FilterGraphNode> rootNodes, int filterLength) {
+            HashSet<FilterGraphNode> visited = new HashSet<FilterGraphNode>();
+            Queue<FilterGraphNode> queue = new Queue<FilterGraphNode>(rootNodes);
+            while (queue.Count > 0) {
+                FilterGraphNode currentNode = queue.Dequeue();
+                if (visited.Contains(currentNode)) {
+                    continue;
+                }
+
+                if (!(currentNode.Filter is BypassFilter || currentNode.Filter.GetType() == typeof(FastConvolver))) {
+                    ConvertToConvolution(currentNode, filterLength);
+                }
+                visited.Add(currentNode);
+                foreach (FilterGraphNode child in currentNode.Children) {
+                    queue.Enqueue(child);
+                }
+            }
+        }
+
         /// <summary>
         /// Check if the graph has cycles.
         /// </summary>
@@ -44,6 +67,32 @@ public static HashSet<FilterGraphNode> MapGraph(IEnumerable<FilterGraphNode> roo
             return visited;
         }
 
+        /// <summary>
+        /// Converts this filter to a convolution and upmerges all children until possible.
+        /// </summary>
+        static void ConvertToConvolution(FilterGraphNode node, int filterLength) {
+            float[] impulse = new float[filterLength];
+            impulse[0] = 1;
+
+            FilterGraphNode downmergeUntil = node;
+            while (true) {
+                downmergeUntil.Filter.Process(impulse);
+                if (downmergeUntil.Children.Count != 1 || downmergeUntil.Children[0].Parents.Count != 1 ||
+                    downmergeUntil.Children[0].Filter is BypassFilter) {
+                    break;
+                }
+                downmergeUntil = downmergeUntil.Children[0];
+            }
+
+            FilterGraphNode[] newChildren = downmergeUntil.Children.ToArray();
+            downmergeUntil.DetachChildren();
+            node.Filter = new FastConvolver(impulse);
+            node.DetachChildren();
+            for (int i = 0; i < newChildren.Length; i++) {
+                node.AddChild(newChildren[i]);
+            }
+        }
+
         /// <summary>
         /// Starting from a single node, checks if the graph has cycles.
         /// </summary>

Cavern/Utilities/ArrayExtensions.cs

@@ -143,6 +143,23 @@ public static float Nearest(this float[] source, float value) {
             return closest;
         }
 
+        /// <summary>
+        /// Removes a <paramref name="value"/> from an <paramref name="array"/> if it contains it.
+        /// </summary>
+        public static void Remove<T>(ref T[] array, T value) {
+            for (int i = 0; i < array.Length; i++) {
+                if (!array[i].Equals(value)) {
+                    continue;
+                }
+
+                T[] replacement = new T[array.Length - 1];
+                Array.Copy(array, 0, replacement, 0, i);
+                Array.Copy(array, i + 1, replacement, i, array.Length - i - 1);
+                array = replacement;
+                return;
+            }
+        }
+
         /// <summary>
         /// Remove the 0 or default elements from the end of an array.
         /// </summary>

CavernSamples/EQAPOtoFIR/Dialogs/SegmentsDialog.xaml

@@ -3,14 +3,14 @@
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
-        xmlns:local="clr-namespace:EQAPOtoFIR.Dialogs"
-        xmlns:EQAPOtoFIR="clr-namespace:EQAPOtoFIR" x:Class="EQAPOtoFIR.Dialogs.SegmentsDialog"
+        xmlns:voidx="clr-namespace:VoidX.WPF"
+        x:Class="EQAPOtoFIR.Dialogs.SegmentsDialog"
         mc:Ignorable="d"
         Title="C array splitting" Height="100" Width="300">
     <Grid>
         <Label Content="Select the amount of output segments:" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top"/>
-        <EQAPOtoFIR:FFTSize x:Name="segments" HorizontalAlignment="Left" Margin="10,0,0,10" Width="63"
-                            Minimum="1" Value="1" Maximum="65536" Height="20" VerticalAlignment="Bottom"/>
+        <voidx:FFTSize x:Name="segments" HorizontalAlignment="Left" Margin="10,0,0,10" Width="63"
+                       Minimum="1" Value="1" Maximum="65536" Height="20" VerticalAlignment="Bottom"/>
         <Button Content="OK" Margin="0,0,10,10" Height="20" VerticalAlignment="Bottom" HorizontalAlignment="Right" Width="75" Click="OK"/>
     </Grid>
 </Window>

CavernSamples/EQAPOtoFIR/EQAPOtoFIR.csproj

@@ -18,6 +18,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
+		<Compile Include="..\VoidX.WPF\FFTSize.cs" Link="Controls\FFTSize.cs" />
 		<Compile Include="..\VoidX.WPF\NumericUpDown.xaml.cs" Link="Controls\NumericUpDown.xaml.cs" />
 	</ItemGroup>
 

CavernSamples/EQAPOtoFIR/MainWindow.xaml

@@ -3,7 +3,6 @@
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
-        xmlns:local="clr-namespace:EQAPOtoFIR"
         xmlns:voidx="clr-namespace:VoidX.WPF"
         mc:Ignorable="d"
         Title="Equalizer APO to FIR" Height="286" Width="404">
@@ -19,7 +18,7 @@
             <voidx:NumericUpDown x:Name="sampleRate" Minimum="8000" Value="48000" Maximum="384000" />
         </GroupBox>
         <GroupBox Header="FFT size" HorizontalAlignment="Left" Height="45" Margin="10,107,0,0" VerticalAlignment="Top" Width="100">
-            <local:FFTSize x:Name="fftSize" Minimum="512" Value="65536" Maximum="1024576" />
+            <voidx:FFTSize x:Name="fftSize" Minimum="512" Value="65536" Maximum="1024576" />
         </GroupBox>
         <GroupBox Header="Bit depth" HorizontalAlignment="Left" Height="95" Margin="115,57,0,0" VerticalAlignment="Top" Width="100">
             <Grid>

CavernSamples/FilterStudio/App.xaml.cs

@@ -8,6 +8,9 @@ public partial class App : Application {
         /// <summary>
         /// Set the language strings with the app launch.
         /// </summary>
-        public App() => Resources.MergedDictionaries.Add(Consts.Language.GetMainWindowStrings());
+        public App() {
+            Resources.MergedDictionaries.Add(Consts.Language.GetMainWindowStrings());
+            Resources.MergedDictionaries.Add(Consts.Language.GetDialogStrings());
+        }
     }
 }

CavernSamples/FilterStudio/Consts/Language.cs

@@ -12,6 +12,11 @@ static class Language {
         /// </summary>
         public static ResourceDictionary GetMainWindowStrings() => mainWindowCache ??= GetFor("MainWindowStrings");
 
+        /// <summary>
+        /// Get the translations of dialogs.
+        /// </summary>
+        public static ResourceDictionary GetDialogStrings() => dialogCache ??= GetFor("DialogStrings");
+
         /// <summary>
         /// Get the translation of a resource file in the user's language, or in English if a translation couldn't be found.
         /// </summary>
@@ -33,5 +38,10 @@ static ResourceDictionary GetFor(string resource) {
         /// The loaded translation of the <see cref="MainWindow"/> for reuse.
         /// </summary>
         static ResourceDictionary mainWindowCache;
+
+        /// <summary>
+        /// The loaded translation of the dialogs for reuse.
+        /// </summary>
+        static ResourceDictionary dialogCache;
     }
 }

CavernSamples/FilterStudio/FilterStudio.csproj

@@ -18,6 +18,8 @@
 		<ApplicationIcon>..\Icon.ico</ApplicationIcon>
 	</PropertyGroup>
 	<ItemGroup>
+	  <Compile Include="..\VoidX.WPF\FFTSize.cs" Link="VoidX.WPF\FFTSize.cs" />
+	  <Compile Include="..\VoidX.WPF\NumericUpDown.xaml.cs" Link="VoidX.WPF\NumericUpDown.xaml.cs" />
 	  <Compile Include="..\VoidX.WPF\ObjectToDataGrid.cs" Link="VoidX.WPF\ObjectToDataGrid.cs" />
 	  <Compile Include="..\VoidX.WPF\QuickContextMenu.cs" Link="VoidX.WPF\QuickContextMenu.cs" />
 	</ItemGroup>
@@ -28,6 +30,9 @@
 		<Resource Include="..\_Common\CavernLogo.png" Link="Resources\CavernLogo.png" />
 	</ItemGroup>
 	<ItemGroup>
+		<Page Include="..\VoidX.WPF\NumericUpDown.xaml" Link="VoidX.WPF\NumericUpDown.xaml">
+		  <Generator>MSBuild:Compile</Generator>
+		</Page>
 		<Page Include="..\_Common\Styles.xaml" Link="Resources\Styles.xaml">
 			<Generator>MSBuild:Compile</Generator>
 		</Page>

CavernSamples/FilterStudio/FilterStudio.csproj.user

@@ -7,14 +7,31 @@
     </ApplicationDefinition>
   </ItemGroup>
   <ItemGroup>
+    <Compile Update="Windows\ConvolutionLengthDialog.xaml.cs">
+      <SubType>Code</SubType>
+    </Compile>
+  </ItemGroup>
+  <ItemGroup>
+    <Page Update="..\VoidX.WPF\NumericUpDown.xaml">
+      <SubType>Designer</SubType>
+    </Page>
     <Page Update="..\_Common\Styles.xaml">
       <SubType>Designer</SubType>
     </Page>
     <Page Update="MainWindow.xaml">
       <SubType>Designer</SubType>
     </Page>
+    <Page Update="Resources\DialogStrings.hu-HU.xaml">
+      <SubType>Designer</SubType>
+    </Page>
+    <Page Update="Resources\DialogStrings.xaml">
+      <SubType>Designer</SubType>
+    </Page>
     <Page Update="Resources\MainWindowStrings.xaml">
       <SubType>Designer</SubType>
     </Page>
+    <Page Update="Windows\ConvolutionLengthDialog.xaml">
+      <SubType>Designer</SubType>
+    </Page>
   </ItemGroup>
 </Project>