untested visualizer complete.

RhythmBullet/RhythmBullet.csproj

@@ -51,6 +51,7 @@
     <Compile Include="Zer01HD\Audio\MusicList.cs" />
     <Compile Include="Zer01HD\Audio\SupportedFormats.cs" />
     <Compile Include="Zer01HD\Audio\TransparentSampleProvider.cs" />
+    <Compile Include="Zer01HD\Audio\Visualizer\HorizontalVisualizer.cs" />
     <Compile Include="Zer01HD\Screens\MainMenu\MainPage.cs" />
     <Compile Include="Zer01HD\Screens\Transitions\FadeAwayTransition.cs" />
     <Compile Include="Zer01HD\Utilities\Camera\Camera2D.cs" />
@@ -151,9 +152,7 @@
     <None Include="app.manifest" />
     <None Include="packages.config" />
   </ItemGroup>
-  <ItemGroup>
+  <ItemGroup />
-    <Folder Include="Zer01HD\Audio\Visualizer\" />
-  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$(MSBuildExtensionsPath)\MonoGame\v3.0\MonoGame.Content.Builder.targets" />
   <Import Project="..\packages\BulletSharp.0.11.1\build\net40-client\BulletSharp.targets" Condition="Exists('..\packages\BulletSharp.0.11.1\build\net40-client\BulletSharp.targets')" />

RhythmBullet/Zer01HD/Audio/MusicController.cs

@@ -9,7 +9,7 @@ using System.Threading.Tasks;
 
 namespace RhythmBullet.Zer01HD.Audio
 {
-    internal class MusicController
+    internal class MusicController : IDisposable
     {
         MusicList musicList;
         WaveOutEvent outputDevice;
@@ -105,5 +105,10 @@ namespace RhythmBullet.Zer01HD.Audio
             return audioInput.CurrentTime;
         }
 
+        public void Dispose()
+        {
+            audioInput?.Dispose();
+            outputDevice?.Dispose();
+        }
     }
 }

RhythmBullet/Zer01HD/Audio/TransparentSampleProvider.cs

@@ -15,7 +15,8 @@ namespace RhythmBullet.Zer01HD.Audio
         private readonly int m; 
         private ISampleProvider source;
         private Complex[] fftBuffer;
-        private float[] spectrum;
+        private volatile bool updatedSpectrum;
+        private readonly float[] currentSpectrum;
         private int channelCount;
         public bool performFFT;
 
@@ -27,7 +28,7 @@ namespace RhythmBullet.Zer01HD.Audio
             source = sampleProvider;
             channelCount = sampleProvider.WaveFormat.Channels;
             fftBuffer = new Complex[FFT_SIZE];
-            spectrum = new float[FFT_SIZE];
+            currentSpectrum = new float[FFT_SIZE];
         }
 
         public WaveFormat WaveFormat
@@ -38,12 +39,20 @@ namespace RhythmBullet.Zer01HD.Audio
             }
         }
 
-        public float GetSpectrumBin(int bin)
+        public float[] GetCurrentSpectrum()
         {
-            lock (spectrum)
+            if (updatedSpectrum)
             {
-                return spectrum[bin];
+                lock (fftBuffer)
+                {
+                    for (int binID = 0; binID < currentSpectrum.Length; binID++)
+                    {
+                        currentSpectrum[binID] = fftBuffer[binID].X;
+                    }
+                }
             }
+
+            return currentSpectrum;
         }
 
         public int Read(float[] buffer, int offset, int count)
@@ -57,14 +66,11 @@ namespace RhythmBullet.Zer01HD.Audio
                 {
                     if (s >= FFT_SIZE)
                     {
-                        FastFourierTransform.FFT(true, m, fftBuffer);
+                        lock (fftBuffer)
-                        lock (spectrum)
                         {
-                            for (int binID = 0; binID < spectrum.Length; binID++)
+                            FastFourierTransform.FFT(true, m, fftBuffer);
-                            {
-                                spectrum[binID] = fftBuffer[binID].X;
-                            }
                         }
+                        updatedSpectrum = true;
                         fftOffset -= FFT_SIZE;
                     }
                     float greatestVal = 0;

RhythmBullet/Zer01HD/Audio/Visualizer/HorizontalVisualizer.cs

@@ -0,0 +1,109 @@
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+using RhythmBullet.Zer01HD.UI.Modular;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace RhythmBullet.Zer01HD.Audio.Visualizer
+{
+    internal class HorizontalVisualizer : UIModule, IDisposable
+    {
+        GraphicsDevice graphicsDevice;
+        Texture2D barTexture;
+        private const int BAR_COUNT = 70;
+        private const int SMOOTH_RANGE = 3;
+        private readonly int binsPerBar;
+        private readonly int spaceBetweenBars;
+        private Rectangle bar;
+        private TransparentSampleProvider tsp;
+        private int[] barValue;
+
+        internal HorizontalVisualizer(TransparentSampleProvider transparentSampleProvider, GraphicsDevice graphicsDevice)
+        {
+            this.graphicsDevice = graphicsDevice;
+            tsp = transparentSampleProvider;
+            bar.Width = (int)(graphicsDevice.Viewport.Width / 70f);
+            spaceBetweenBars = (int)(0.25f * bar.Width);
+            bar.Width -= spaceBetweenBars;
+
+            barTexture = new Texture2D(graphicsDevice, 1, 1);
+            barTexture.SetData(new[] { Color.White });
+            binsPerBar = tsp.GetCurrentSpectrum().Length / BAR_COUNT;
+            barValue = new int[BAR_COUNT];
+        }
+
+        public override void Update(GameTime gameTime)
+        {
+            UpdateBars((float)gameTime.ElapsedGameTime.TotalSeconds);
+            AverageBars();
+            base.Update(gameTime);
+        }
+
+        public override void Draw(SpriteBatch batch)
+        {
+            for (int i = 0; i < BAR_COUNT; i++)
+            {
+                bar.X = (i * (bar.Width + spaceBetweenBars)) + Bounds.X;
+                bar.Y = Bounds.Y;
+
+                bar.Height = barValue[i];
+                batch.Draw(barTexture, bar, Color);
+
+                bar.Height = -barValue[BAR_COUNT - i - 1];
+                batch.Draw(barTexture, bar, Color);
+            }
+            base.Draw(batch);
+        }
+
+        private void UpdateBars(float delta)
+        {
+            const float ALPHA = 0.5f;
+            float[] spectrum = tsp.GetCurrentSpectrum();
+
+            for (int barID = 0; barID < BAR_COUNT; barID++)
+            {
+                int targetBarHeight = 0;
+
+                for (int bin = barID * binsPerBar; bin < (barID + 1) * (binsPerBar); bin++)
+                {
+                    targetBarHeight += (int)spectrum[bin];
+                }
+                targetBarHeight /= binsPerBar;
+
+                int distance = targetBarHeight - barValue[barID];
+                distance *= (int)Math.Round((1.0f - Math.Pow(1 - ALPHA, delta / 0.02f)));
+                barValue[barID] += distance;
+            }
+        }
+
+        private void AverageBars()
+        {
+            for (int barID = 0; barID < BAR_COUNT; barID++)
+            {
+                int terms = 0;
+                for (int pos = 0; pos < SMOOTH_RANGE; pos++)
+                {
+                    if (barID + pos < BAR_COUNT)
+                    {
+                        barValue[barID] += barValue[barID + pos];
+                        terms++;
+                    }
+                    if (barID - pos > 0)
+                    {
+                        barValue[barID] += barValue[barID - pos];
+                        terms++;
+                    }
+                }
+                barValue[barID] /= terms;
+            }
+        }
+
+        public void Dispose()
+        {
+            barTexture.Dispose();
+        }
+    }
+}

RhythmBullet/Zer01HD/Utilities/Camera/Camera2D.cs

@@ -32,11 +32,14 @@ namespace RhythmBullet.Zer01HD.Utilities.Camera
                 Matrix.CreateTranslation(new Vector3(bounds.Width * 0.5f, bounds.Height * 0.5f, 0f));
         }
 
-        public void LinearInterpolationToPosition(float alpha, Vector2 targetPosition)
+        public void LinearInterpolationToPosition(float alpha, Vector2 targetPosition, float delta)
         {
-            if (alpha < 0 && alpha > 1f) throw new ArgumentException("Alpha can't be greater than 1f, or less than 0.");
+            if (alpha <= 0 && alpha > 1f) throw new ArgumentException("Alpha can't be greater than 1f, less than or equal to 0.");
-            Position.X = MathHelper.Lerp(Position.X, targetPosition.X, alpha);
+
-            Position.Y = MathHelper.Lerp(Position.Y, targetPosition.Y, alpha);
+            Vector2 distance = targetPosition - Position;
+            distance *= (float)(1.0f - Math.Pow(1 - alpha, delta / 0.02f));
+
+            Position += distance;
         }
     }
 }

RhythmBullet/Zer01HD/Utilities/UI/Book/Book.cs

@@ -45,7 +45,7 @@ namespace RhythmBullet.Zer01HD.UI.Book
                 Rectangle targetBounds = targetPage.Bounds;
                 position.X = targetBounds.X + (targetBounds.Width * 0.5f);
                 position.Y = targetBounds.Y + (targetBounds.Height * 0.5f);
-                camera.LinearInterpolationToPosition(0.4f, position);
+                camera.LinearInterpolationToPosition(0.4f, position, (float)gameTime.ElapsedGameTime.TotalSeconds);
                 if (camera.Position == position)
                 {
                     targetPage = null;