Basic filter additions to graph

Cavern.QuickEQ.Format/ConfigurationFile/ConfigurationFile.cs

@@ -1,5 +1,7 @@
 using System.Collections.Generic;
 
+using Cavern.Channels;
+using Cavern.Filters;
 using Cavern.Filters.Utilities;
 
 namespace Cavern.Format.ConfigurationFile {
@@ -17,10 +19,10 @@ public abstract class ConfigurationFile {
         /// <summary>
         /// Create an empty configuration file with the passed input channel names/labels.
         /// </summary>
-        public ConfigurationFile(string[] inputs) {
+        protected ConfigurationFile(string[] inputs) {
             InputChannels = new (string name, FilterGraphNode root)[inputs.Length];
             for (int i = 0; i < inputs.Length; i++) {
-                InputChannels[i] = (inputs[i], new FilterGraphNode(null));
+                InputChannels[i] = (inputs[i], new FilterGraphNode(new InputChannel(inputs[i])));
             }
         }
 

Cavern.QuickEQ.Format/ConfigurationFile/EqualizerAPOConfigurationFile.cs

@@ -25,7 +25,7 @@ public EqualizerAPOConfigurationFile(string path, int sampleRate) : base(channel
             AddConfigFile(path, lastNodes, activeChannels, sampleRate);
 
             for (int i = 0; i < channelLabels.Length; i++) { // Output markers
-                lastNodes[channelLabels[i]].AddChild(new FilterGraphNode(new BypassFilter(channelLabels[i] + '\'')));
+                lastNodes[channelLabels[i]].AddChild(new FilterGraphNode(new OutputChannel(channelLabels[i])));
             }
             Optimize();
         }

Cavern.QuickEQ.Format/Filters/InputChannel.cs

@@ -0,0 +1,30 @@
+using Cavern.Channels;
+using Cavern.Format.ConfigurationFile;
+
+namespace Cavern.Filters {
+    /// <summary>
+    /// Marks an input channel on a parsed <see cref="ConfigurationFile"/> graph.
+    /// </summary>
+    /// <remarks>This filter is part of the Cavern.QuickEQ.Format library and is not available in the Cavern library's Filters namespace,
+    /// because it shall only be created by <see cref="ConfigurationFile"/>s.</remarks>
+    public class InputChannel : BypassFilter {
+        /// <summary>
+        /// The channel for which this filter marks the beginning of the filter pipeline.
+        /// </summary>
+        public ReferenceChannel Channel { get; }
+
+        /// <summary>
+        /// Marks an input channel on a parsed <see cref="ConfigurationFile"/> graph.
+        /// </summary>
+        /// <param name="channel">The channel for which this filter marks the beginning of the filter pipeline</param>
+        protected internal InputChannel(ReferenceChannel channel) : base(channel.GetShortName() + " input") => Channel = channel;
+
+        /// <summary>
+        /// Marks an input channel on a parsed <see cref="ConfigurationFile"/> graph.
+        /// </summary>
+        /// <param name="channel">The channel for which this filter marks the beginning of the filter pipeline</param>
+        protected internal InputChannel(string channel) :
+            base(ReferenceChannelExtensions.FromStandardName(channel).GetShortName() + " input") =>
+            Channel = ReferenceChannelExtensions.FromStandardName(channel);
+    }
+}

Cavern.QuickEQ.Format/Filters/OutputChannel.cs

@@ -0,0 +1,30 @@
+using Cavern.Channels;
+using Cavern.Format.ConfigurationFile;
+
+namespace Cavern.Filters {
+    /// <summary>
+    /// Marks an output channel on a parsed <see cref="ConfigurationFile"/> graph.
+    /// </summary>
+    /// <remarks>This filter is part of the Cavern.QuickEQ.Format library and is not available in the Cavern library's Filters namespace,
+    /// because it shall only be created by <see cref="ConfigurationFile"/>s.</remarks>
+    public class OutputChannel : BypassFilter {
+        /// <summary>
+        /// The channel for which this filter marks the end of the filter pipeline.
+        /// </summary>
+        public ReferenceChannel Channel { get; }
+
+        /// <summary>
+        /// Marks an output channel on a parsed <see cref="ConfigurationFile"/> graph.
+        /// </summary>
+        /// <param name="channel">The channel for which this filter marks the end of the filter pipeline</param>
+        protected internal OutputChannel(ReferenceChannel channel) : base(channel.GetShortName() + " output") => Channel = channel;
+
+        /// <summary>
+        /// Marks an output channel on a parsed <see cref="ConfigurationFile"/> graph.
+        /// </summary>
+        /// <param name="channel">The channel for which this filter marks the end of the filter pipeline</param>
+        protected internal OutputChannel(string channel) :
+            base(ReferenceChannelExtensions.FromStandardName(channel).GetShortName() + " output") =>
+            Channel = ReferenceChannelExtensions.FromStandardName(channel);
+    }
+}

Cavern/Channels/ChannelPrototype.Consts.cs

@@ -259,7 +259,7 @@ public static readonly ChannelPrototype
         /// <summary>
         /// Semi-standard (Equalizer APO) channel names.
         /// </summary>
-        const string frontLeftMark = "L",
+        internal const string frontLeftMark = "L",
             frontRightMark = "R",
             frontCenterMark = "C",
             screenLFEMark = "LFE",

Cavern/Channels/ChannelPrototype.cs

@@ -118,7 +118,7 @@ public static ChannelPrototype Get(int channel, int channels) {
         /// </summary>
         public static ChannelPrototype[] Get(ReferenceChannel[] source) {
             ChannelPrototype[] result = new ChannelPrototype[source.Length];
-            for (int i = 0; i < source.Length; ++i) {
+            for (int i = 0; i < source.Length; i++) {
                 result[i] = Mapping[(int)source[i]];
             }
             return result;
@@ -129,7 +129,7 @@ public static ChannelPrototype[] Get(ReferenceChannel[] source) {
         /// </summary>
         public static ChannelPrototype[] GetAlternative(ReferenceChannel[] source) {
             ChannelPrototype[] result = new ChannelPrototype[source.Length];
-            for (int i = 0; i < source.Length; ++i) {
+            for (int i = 0; i < source.Length; i++) {
                 int index = (int)source[i];
                 ChannelPrototype old = Mapping[index];
                 Channel moved = new Channel(AlternativePositions[index], old.LFE);
@@ -147,7 +147,7 @@ public static ChannelPrototype[] GetAlternative(ReferenceChannel[] source) {
         /// </summary>
         public static string[] GetNames(ReferenceChannel[] source) {
             string[] result = new string[source.Length];
-            for (int i = 0; i < source.Length; ++i) {
+            for (int i = 0; i < source.Length; i++) {
                 result[i] = Mapping[(int)source[i]].Name;
             }
             return result;
@@ -239,7 +239,7 @@ static ReferenceChannel[] GetStandardMatrix(ReferenceChannel[][] database, int c
             ReferenceChannel[] matrix = database[subcount];
             if (subcount != count) {
                 Array.Resize(ref matrix, count);
-                for (int i = subcount; i < count; ++i) {
+                for (int i = subcount; i < count; i++) {
                     matrix[i] = ReferenceChannel.Unknown;
                 }
             }

Cavern/Channels/ReferenceChannelExtensions.cs

@@ -26,5 +26,32 @@ public static bool IsHeight(this ReferenceChannel channel) =>
             (channel >= ReferenceChannel.TopFrontLeft && channel <= ReferenceChannel.TopSideRight) ||
             channel == ReferenceChannel.TopFrontCenter || channel == ReferenceChannel.GodsVoice ||
             (channel >= ReferenceChannel.TopRearLeft && channel <= ReferenceChannel.TopRearCenter);
+
+        /// <summary>
+        /// Converts a standard channel shorthand to a <see cref="ReferenceChannel"/>.
+        /// </summary>
+        public static ReferenceChannel FromStandardName(string name) {
+            switch (name) {
+                case ChannelPrototype.frontLeftMark:
+                    return ReferenceChannel.FrontLeft;
+                case ChannelPrototype.frontRightMark:
+                    return ReferenceChannel.FrontRight;
+                case ChannelPrototype.frontCenterMark:
+                    return ReferenceChannel.FrontCenter;
+                case ChannelPrototype.screenLFEMark:
+                case ChannelPrototype.subwooferMark:
+                    return ReferenceChannel.ScreenLFE;
+                case ChannelPrototype.rearLeftMark:
+                    return ReferenceChannel.RearLeft;
+                case ChannelPrototype.rearRightMark:
+                    return ReferenceChannel.RearRight;
+                case ChannelPrototype.sideLeftMark:
+                    return ReferenceChannel.SideLeft;
+                case ChannelPrototype.sideRightMark:
+                    return ReferenceChannel.SideRight;
+                default:
+                    return ReferenceChannel.Unknown;
+            }
+        }
     }
 }

Cavern/Filters/Allpass.cs

@@ -6,6 +6,9 @@ namespace Cavern.Filters {
     /// Simple first-order allpass filter.
     /// </summary>
     public class Allpass : PhaseSwappableBiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.Allpass;
+
         /// <summary>
         /// Simple first-order allpass filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/Bandpass.cs

@@ -8,6 +8,9 @@ namespace Cavern.Filters {
     /// Simple first-order bandpass filter.
     /// </summary>
     public class Bandpass : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.Bandpass;
+
         /// <summary>
         /// Simple first-order bandpass filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/BiquadFilter.cs

@@ -70,6 +70,11 @@ public double Gain {
         public float b2 { get; protected set; }
 #pragma warning restore IDE1006 // Naming Styles
 
+        /// <summary>
+        /// The enumerated type of this filter.
+        /// </summary>
+        public abstract BiquadFilterType FilterType { get; }
+
         /// <summary>
         /// Center frequency (-3 dB point) of the filter.
         /// </summary>
@@ -225,6 +230,6 @@ protected void SetupPass(float cosW0, float alpha, float divisor, float b1Pre) {
         /// <summary>
         /// Display the filter's parameters when converting to string.
         /// </summary>
-        public override string ToString() => $"Biquad filter at {centerFreq} Hz, Q: {q}, gain: {gain} dB";
+        public override string ToString() => $"{FilterType} at {centerFreq} Hz, Q: {q}, gain: {gain} dB";
     }
 }

Cavern/Filters/HighShelf.cs

@@ -8,6 +8,9 @@ namespace Cavern.Filters {
     /// Simple first-order high shelf filter.
     /// </summary>
     public class HighShelf : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.HighShelf;
+
         /// <summary>
         /// Simple first-order high shelf filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/Highpass.cs

@@ -7,6 +7,9 @@ namespace Cavern.Filters {
     /// Simple first-order highpass filter.
     /// </summary>
     public class Highpass : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.Highpass;
+
         /// <summary>
         /// Simple first-order highpass filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/LowShelf.cs

@@ -8,6 +8,9 @@ namespace Cavern.Filters {
     /// Simple first-order low shelf filter.
     /// </summary>
     public class LowShelf : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.LowShelf;
+
         /// <summary>
         /// Simple first-order low shelf filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/Lowpass.cs

@@ -7,6 +7,9 @@ namespace Cavern.Filters {
     /// Simple first-order lowpass filter.
     /// </summary>
     public class Lowpass : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.Lowpass;
+
         /// <summary>
         /// Simple first-order lowpass filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/Notch.cs

@@ -6,6 +6,9 @@ namespace Cavern.Filters {
     /// Simple first-order notch filter.
     /// </summary>
     public class Notch : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.Notch;
+
         /// <summary>
         /// Simple first-order notch filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/PeakingEQ.cs

@@ -6,6 +6,9 @@ namespace Cavern.Filters {
     /// Simple first-order peaking filter.
     /// </summary>
     public class PeakingEQ : BiquadFilter {
+        /// <inheritdoc/>
+        public override BiquadFilterType FilterType => BiquadFilterType.PeakingEQ;
+
         /// <summary>
         /// Simple first-order peaking filter with maximum flatness and no additional gain.
         /// </summary>

Cavern/Filters/Utilities/FilterGraphNode.cs

@@ -36,6 +36,28 @@ public class FilterGraphNode {
         /// <param name="filter">The wrapped filter</param>
         public FilterGraphNode(Filter filter) => Filter = filter;
 
+        /// <summary>
+        /// Place a <see cref="FilterGraphNode"/> between this and the <see cref="children"/>.
+        /// </summary>
+        public void AddBeforeChildren(FilterGraphNode newChild) {
+            newChild.children.AddRange(children);
+            for (int i = 0, c = children.Count; i < c; i++) {
+                children[i].parents.Clear();
+                children[i].parents.Add(newChild);
+            }
+            children.Clear();
+            AddChild(newChild);
+        }
+
+        /// <summary>
+        /// Place a <paramref name="filter"/> between this and the <see cref="children"/> and return the new node containing that filter.
+        /// </summary>
+        public FilterGraphNode AddBeforeChildren(Filter filter) {
+            FilterGraphNode node = new FilterGraphNode(filter);
+            AddBeforeChildren(node);
+            return node;
+        }
+
         /// <summary>
         /// Append a node to process this filter's result in the filter graph.
         /// </summary>

CavernSamples/Cavern.WPF/BiquadEditor.xaml

@@ -6,11 +6,12 @@
         xmlns:local="clr-namespace:Cavern.WPF"
         x:Class="Cavern.WPF.BiquadEditor"
         mc:Ignorable="d"
-        Title="Biquad Editor" Width="536" Height="370">
+        Title="Biquad Editor" Width="536" Height="372">
     <Grid>
         <Image x:Name="image" Margin="10,10,0,0" Height="200" HorizontalAlignment="Left" VerticalAlignment="Top" Width="500"/>
         <TextBlock Margin="10,218,0,0" HorizontalAlignment="Left" VerticalAlignment="Top" Text="Filter type:"/>
-        <ComboBox x:Name="filterTypes" Margin="130,215,0,0" HorizontalAlignment="Left" VerticalAlignment="Top" Width="120" SelectionChanged="FilterTypeChanged"/>
+        <ComboBox x:Name="filterTypes" Margin="130,215,0,0" HorizontalAlignment="Left" VerticalAlignment="Top" Width="120"
+                  SelectionChanged="FilterTypeChanged"/>
         <TextBlock Margin="10,243,0,0" HorizontalAlignment="Left" VerticalAlignment="Top" Text="Center frequency:"/>
         <TextBox x:Name="centerFreq" Margin="130,242,0,0" HorizontalAlignment="Left" VerticalAlignment="Top" Width="120" Text="632.456"
                  TextChanged="NumericFilterDataChanged"/>
@@ -22,5 +23,12 @@
                  TextChanged="NumericFilterDataChanged"/>
         <CheckBox x:Name="swapPhase" Margin="10,311,0,0" HorizontalAlignment="Left" VerticalAlignment="Top" Content="Swap phase"
                   Checked="PhaseSwapChanged" Unchecked="PhaseSwapChanged"/>
+        <CheckBox x:Name="spectrumColorDisplay" Margin="0,215,10,0" HorizontalAlignment="Right" VerticalAlignment="Top" Width="100"
+                  Content="Spectrum" Checked="DisableCheck"/>
+        <CheckBox x:Name="phaseColorDisplay" Margin="0,235,10,0" HorizontalAlignment="Right" VerticalAlignment="Top" Width="100"
+                  Content="Phase" Checked="DisableCheck"/>
+        <Button Margin="0,0,95,10" Width="80" Height="20" HorizontalAlignment="Right" VerticalAlignment="Bottom" Content="OK" Click="OK"/>
+        <Button Margin="0,0,10,10" Width="80" Height="20" HorizontalAlignment="Right" VerticalAlignment="Bottom" Content="Cancel"
+                Click="Cancel"/>
     </Grid>
 </Window>