Changing sound frequency for game

Hi!
I wanted to be able to change a sound frequency according to the strength applied to a element inside a game. Based on this thread I changed the sample to allow to change at real time the frequency of the sound being played.

The code that does the thing is:

   1: BufferDescription d = new BufferDescription();

   2: d.ControlFrequency = true;

   3: sound = new SecondaryBuffer("C:\\Windows\\Media\\ding.wav", d, applicationDevice);

   4: sound.Frequency = 0; //The default frequency

   5: sound.Play(0, BufferPlayFlags.Looping);

   6: if you want to change the frequency:

   7: sound.Frequency = <some value>;

Here is the complete code:

(you need to add a reference to Microsoft.DirectX.DirectSound)

   1: using System;

   2: using System.IO;

   3: using System.Drawing;

   4: using System.Collections;

   5: using System.ComponentModel;

   6: using System.Windows.Forms;

   7: using System.Data;

   8:  

   9: using Microsoft.DirectX.DirectSound;

  10:  

  11: namespace Noisey

  12: {

  13:     /// <summary>

  14:     /// Very simple test form

  15:     /// </summary>

  16:     public class MainForm : System.Windows.Forms.Form

  17:     {

  18:         private System.Windows.Forms.Button btnPlay;

  19:         /// <summary>

  20:         /// Required designer variable.

  21:         /// </summary>

  22:         private System.ComponentModel.Container components = null;

  23:  

  24:         Device applicationDevice;

  25:         SecondaryBuffer sound;

  26:         private BufferDescription d;

  27:  

  28:         private TrackBar trackBar1;

  29:         private TextBox txtFreq;

  30:         private Label label1;

  31:         private Label label2;

  32:         private Button btnStop;

  33:         private OpenFileDialog openFileDialog1;

  34:         private Button btnNewFile;

  35:         private Label lblFile;

  36:         private Label label3;

  37:         

  38:         

  39:  

  40:         public MainForm()

  41:         {

  42:             //

  43:             // Required for Windows Form Designer support

  44:             //

  45:             InitializeComponent();

  46:  

  47:             //

  48:             // Add any constructor code after InitializeComponent call

  49:             //

  50:             applicationDevice = new Device();

  51:             applicationDevice.SetCooperativeLevel(this, CooperativeLevel.Normal);

  52:             

  53:             d = new BufferDescription();

  54:             // Set descriptor’s flags

  55:             d.ControlPan = true;

  56:             d.ControlVolume = false;

  57:             d.ControlFrequency = true;

  58:             d.ControlEffects = false;

  59:  

  60:             //Load a default file

  61:             sound = new SecondaryBuffer("C:\\Windows\\Media\\ding.wav", d, applicationDevice);

  62:             sound.Frequency = 0; //The default frequency

  63:  

  64:             //Disable stop button because it's not playing yet.

  65:             btnStop.Enabled = false;

  66:         }

  67:  

  68:         /// <summary>

  69:         /// Clean up any resources being used.

  70:         /// </summary>

  71:         protected override void Dispose(bool disposing)

  72:         {

  73:             if (disposing)

  74:             {

  75:                 if (components != null)

  76:                 {

  77:                     components.Dispose();

  78:                 }

  79:             }

  80:             base.Dispose(disposing);

  81:         }

  82:  

  83:         #region Windows Form Designer generated code

  84:         /// <summary>

  85:         /// Required method for Designer support - do not modify

  86:         /// the contents of this method with the code editor.

  87:         /// </summary>

  88:         private void InitializeComponent()

  89:         {

  90:             this.btnPlay = new System.Windows.Forms.Button();

  91:             this.trackBar1 = new System.Windows.Forms.TrackBar();

  92:             this.txtFreq = new System.Windows.Forms.TextBox();

  93:             this.label1 = new System.Windows.Forms.Label();

  94:             this.label2 = new System.Windows.Forms.Label();

  95:             this.btnStop = new System.Windows.Forms.Button();

  96:             this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();

  97:             this.btnNewFile = new System.Windows.Forms.Button();

  98:             this.lblFile = new System.Windows.Forms.Label();

  99:             this.label3 = new System.Windows.Forms.Label();

 100:             ((System.ComponentModel.ISupportInitialize)(this.trackBar1)).BeginInit();

 101:             this.SuspendLayout();

 102:             // 

 103:             // btnPlay

 104:             // 

 105:             this.btnPlay.Location = new System.Drawing.Point(18, 64);

 106:             this.btnPlay.Name = "btnPlay";

 107:             this.btnPlay.Size = new System.Drawing.Size(87, 20);

 108:             this.btnPlay.TabIndex = 0;

 109:             this.btnPlay.Text = "Play Sound";

 110:             this.btnPlay.Click += new System.EventHandler(this.btnPlay_Click);

 111:             // 

 112:             // trackBar1

 113:             // 

 114:             this.trackBar1.Location = new System.Drawing.Point(37, 124);

 115:             this.trackBar1.Maximum = 50000;

 116:             this.trackBar1.Minimum = 1000;

 117:             this.trackBar1.Name = "trackBar1";

 118:             this.trackBar1.Size = new System.Drawing.Size(190, 45);

 119:             this.trackBar1.TabIndex = 1;

 120:             this.trackBar1.Value = 30000;

 121:             this.trackBar1.ValueChanged += new System.EventHandler(this.trackBar1_ValueChanged);

 122:             // 

 123:             // txtFreq

 124:             // 

 125:             this.txtFreq.Enabled = false;

 126:             this.txtFreq.Location = new System.Drawing.Point(43, 185);

 127:             this.txtFreq.Name = "txtFreq";

 128:             this.txtFreq.Size = new System.Drawing.Size(100, 20);

 129:             this.txtFreq.TabIndex = 2;

 130:             // 

 131:             // label1

 132:             // 

 133:             this.label1.AutoSize = true;

 134:             this.label1.Location = new System.Drawing.Point(40, 108);

 135:             this.label1.Name = "label1";

 136:             this.label1.Size = new System.Drawing.Size(100, 13);

 137:             this.label1.TabIndex = 3;

 138:             this.label1.Text = "Frequency Change:";

 139:             // 

 140:             // label2

 141:             // 

 142:             this.label2.AutoSize = true;

 143:             this.label2.Location = new System.Drawing.Point(43, 166);

 144:             this.label2.Name = "label2";

 145:             this.label2.Size = new System.Drawing.Size(97, 13);

 146:             this.label2.TabIndex = 4;

 147:             this.label2.Text = "Current Frequency:";

 148:             // 

 149:             // btnStop

 150:             // 

 151:             this.btnStop.Location = new System.Drawing.Point(111, 61);

 152:             this.btnStop.Name = "btnStop";

 153:             this.btnStop.Size = new System.Drawing.Size(88, 21);

 154:             this.btnStop.TabIndex = 5;

 155:             this.btnStop.Text = "Stop";

 156:             this.btnStop.UseVisualStyleBackColor = true;

 157:             this.btnStop.Click += new System.EventHandler(this.btnStop_Click);

 158:             // 

 159:             // openFileDialog1

 160:             // 

 161:             this.openFileDialog1.FileName = "openFileDialog1";

 162:             this.openFileDialog1.FileOk += new System.ComponentModel.CancelEventHandler(this.openFileDialog1_FileOk);

 163:             // 

 164:             // btnNewFile

 165:             // 

 166:             this.btnNewFile.Location = new System.Drawing.Point(205, 61);

 167:             this.btnNewFile.Name = "btnNewFile";

 168:             this.btnNewFile.Size = new System.Drawing.Size(75, 23);

 169:             this.btnNewFile.TabIndex = 6;

 170:             this.btnNewFile.Text = "Open";

 171:             this.btnNewFile.UseVisualStyleBackColor = true;

 172:             this.btnNewFile.Click += new System.EventHandler(this.btnNewFile_Click);

 173:             // 

 174:             // lblFile

 175:             // 

 176:             this.lblFile.AutoSize = true;

 177:             this.lblFile.Location = new System.Drawing.Point(23, 30);

 178:             this.lblFile.Name = "lblFile";

 179:             this.lblFile.Size = new System.Drawing.Size(148, 13);

 180:             this.lblFile.TabIndex = 7;

 181:             this.lblFile.Text = "C:\\Windows\\Media\\ding.wav";

 182:             // 

 183:             // label3

 184:             // 

 185:             this.label3.AutoSize = true;

 186:             this.label3.Location = new System.Drawing.Point(23, 9);

 187:             this.label3.Name = "label3";

 188:             this.label3.Size = new System.Drawing.Size(63, 13);

 189:             this.label3.TabIndex = 8;

 190:             this.label3.Text = "Current File:";

 191:             // 

 192:             // MainForm

 193:             // 

 194:             this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);

 195:             this.ClientSize = new System.Drawing.Size(292, 260);

 196:             this.Controls.Add(this.label3);

 197:             this.Controls.Add(this.lblFile);

 198:             this.Controls.Add(this.btnNewFile);

 199:             this.Controls.Add(this.btnStop);

 200:             this.Controls.Add(this.label2);

 201:             this.Controls.Add(this.label1);

 202:             this.Controls.Add(this.txtFreq);

 203:             this.Controls.Add(this.trackBar1);

 204:             this.Controls.Add(this.btnPlay);

 205:             this.Name = "MainForm";

 206:             this.Text = "Sound Frequency Changer";

 207:             ((System.ComponentModel.ISupportInitialize)(this.trackBar1)).EndInit();

 208:             this.ResumeLayout(false);

 209:             this.PerformLayout();

 210:  

 211:         }

 212:         #endregion

 213:  

 214:         /// <summary>

 215:         /// The main entry point for the application.

 216:         /// </summary>

 217:         [STAThread]

 218:         static void Main()

 219:         {

 220:             Application.Run(new MainForm());

 221:         }

 222:  

 223:         private void btnPlay_Click(object sender, System.EventArgs e)

 224:         {

 225:             

 226:             sound.Play(0, BufferPlayFlags.Looping);

 227:             btnPlay.Enabled = false;

 228:             btnStop.Enabled = true;

 229:         }

 230:  

 231:         private void trackBar1_ValueChanged(object sender, EventArgs e)

 232:         {

 233:             txtFreq.Text = trackBar1.Value.ToString();

 234:             sound.Frequency = trackBar1.Value;

 235:             btnPlay.Enabled = true;

 236:         }

 237:  

 238:         private void btnNewFile_Click(object sender, EventArgs e)

 239:         {

 240:             openFileDialog1.Filter = "wav files (*.wav)|*.wav|All files (*.*)|*.*";

 241:             openFileDialog1.ShowDialog();

 242:         }

 243:  

 244:         private void openFileDialog1_FileOk(object sender, CancelEventArgs e)

 245:         {

 246:             sound.Stop();

 247:             btnPlay.Enabled = true;

 248:             btnStop.Enabled = false;

 249:             lblFile.Text = openFileDialog1.FileName;

 250:             sound = new SecondaryBuffer(openFileDialog1.FileName, d, applicationDevice);

 251:             sound.Frequency = 0; //The default frequency

 252:  

 253:         }

 254:  

 255:         private void btnStop_Click(object sender, EventArgs e)

 256:         {

 257:             sound.Stop();

 258:             btnStop.Enabled = false;

 259:             btnPlay.Enabled = true;

 260:         }

 261:     }

 262: }

 263:  

 264:  

This will allow me to use a beam or phaser sound to create the appearance of strength applied on a element.