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/*
* Created by: Leslie Sanford
*
* Contact: jabberdabber@hotmail.com
*
* Last modified: 09/27/2004
*/
using System;
using System.ComponentModel;
using System.Collections;
using System.Diagnostics;
namespace Multimedia.Midi
{
/// <summary>
/// Plays back sequences.
/// </summary>
public sealed class Sequencer : System.ComponentModel.Component
{
#region Sequencer Members
#region Fields
// The sequence position.
private int position = 0;
// Indicates whether or not the sequencer should seek the position
// before beginning playback.
private bool seekPosition = false;
// The sequence to playback.
private Sequence seq;
// The version of the sequence.
private int sequenceVersion;
// The sequence player for controlling sequence playback.
private SequencePlayer player;
// The MIDI clock for controlling playback timing.
private SlaveClock clock;
// The input device used for receiving MIDI messages.
private InputDevice inDevice;
// The output device used for sending MIDI messages.
private OutputDevice outDevice;
// The tick generator used for timing the playback of MIDI messages.
private TickGenerator tickGen;
// The component container.
private IContainer components;
#endregion
#region Events
/// <summary>
/// Occurs when the tempo changes.
/// </summary>
public event EventHandler TempoChanged;
#endregion
#region Construction
/// <summary>
/// Initializes an instance of the Sequencer class with the specified
/// component container.
/// </summary>
/// <param name="container">
/// The component container.
/// </param>
public Sequencer(System.ComponentModel.IContainer container)
{
//
// Required for Windows.Forms Class Composition Designer support
//
container.Add(this);
InitializeComponent();
InitializeSequencer();
}
/// <summary>
/// Initializes an instance of the Sequencer class.
/// </summary>
public Sequencer()
{
//
// Required for Windows.Forms Class Composition Designer support
//
InitializeComponent();
InitializeSequencer();
}
#endregion
#region Methods
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
inDevice.Close();
outDevice.Close();
clock.Dispose();
if(components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Component Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.inDevice = new Multimedia.Midi.InputDevice(this.components);
this.outDevice = new Multimedia.Midi.OutputDevice(this.components);
this.tickGen = new Multimedia.Midi.TickGenerator(this.components);
//
// outDevice
//
this.outDevice.RunningStatusEnabled = true;
//
// tickGen
//
this.tickGen.Ppqn = 96;
this.tickGen.Tempo = 500000;
this.tickGen.Tick += new System.EventHandler(this.TickHandler);
}
#endregion
/// <summary>
/// Initializes the sequencer.
/// </summary>
private void InitializeSequencer()
{
seq = new Sequence();
sequenceVersion = seq.Version;
player = new SequencePlayer(outDevice, tickGen, seq);
player.EndOfSequenceReached +=
new EventHandler(EndOfSequenceReachedHandler);
clock = new SlaveClock(inDevice, outDevice, tickGen);
clock.Starting += new EventHandler(StartingHandler);
clock.Continuing += new EventHandler(ContinuingHandler);
clock.Stopping += new EventHandler(StoppingHandler);
clock.PositionChanged += new PositionChangedEventHandler(PositionChangedHandler);
tickGen.TempoChanged += new EventHandler(OnTempoChanged);
if(InputDevice.DeviceCount > 0)
InputDeviceID = 0;
if(OutputDevice.DeviceCount > 0)
OutputDeviceID = 0;
}
/// <summary>
/// Starts playback at the beginning of the sequence.
/// </summary>
public void Start()
{
clock.Start();
}
/// <summary>
/// Continues playback from the current position.
/// </summary>
public void Continue()
{
// Guard.
if(Position >= Sequence.Length)
return;
clock.Continue();
}
/// <summary>
/// Stops playback.
/// </summary>
public void Stop()
{
clock.Stop();
}
/// <summary>
/// Attaches a delegate to the internal tick generator the sequencer
/// uses for timing playback.
/// </summary>
/// <param name="handler">
/// The delegate to attach to the tick generator.
/// </param>
/// <remarks>
/// Attaching a delegate to a sequencer's tick generator allows a
/// client to synchronize itself with the sequencer's playback.
/// </remarks>
public void AttachToTickGenerator(EventHandler handler)
{
tickGen.Tick += handler;
}
/// <summary>
/// Detaches a delegate from the internal tick generator the sequencer
/// uses for timing playback.
/// </summary>
/// <param name="handler">
/// The delegate to detach from the tick generator.
/// </param>
public void DetachFromTickGenerator(EventHandler handler)
{
tickGen.Tick -= handler;
}
/// <summary>
/// Sets the mute state of a track.
/// </summary>
/// <param name="index">
/// The index into the sequence of the track to mute.
/// </param>
/// <param name="mute">
/// A value indicating whether or not to mute the track.
/// </param>
public void MuteTrack(int index, bool mute)
{
player.MuteTrack(index, mute);
}
/// <summary>
/// Sets the solo state of a track.
/// </summary>
/// <param name="index">
/// The index into the sequence of the track to solo.
/// </param>
/// <param name="solo">
/// A value indicating whether or not to solo the track.
/// </param>
public void SoloTrack(int index, bool solo)
{
player.SoloTrack(index, solo);
}
/// <summary>
/// Handles tick events generated by the tick generator.
/// </summary>
/// <param name="sender">
/// The tick generator responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void TickHandler(object sender, EventArgs e)
{
position++;
}
/// <summary>
/// Handles the starting event generated by the MIDI clock.
/// </summary>
/// <param name="sender">
/// The MIDI clock responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void StartingHandler(object sender, EventArgs e)
{
// Lock the sequence so that it cannot be modified during playback.
Sequence.LockSequence(this, true);
outDevice.Reset();
if(sequenceVersion != Sequence.Version)
{
PreparePlayer();
sequenceVersion = Sequence.Version;
}
Position = 0;
player.Seek(0);
}
/// <summary>
/// Handles the continuing event generated by the MIDI clock.
/// </summary>
/// <param name="sender">
/// The MIDI clock responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void ContinuingHandler(object sender, EventArgs e)
{
// Lock the sequence so that it cannot be modified during playback.
Sequence.LockSequence(this, true);
if(sequenceVersion != Sequence.Version)
{
PreparePlayer();
sequenceVersion = Sequence.Version;
seekPosition = true;
}
if(seekPosition)
{
player.Seek(position);
seekPosition = false;
}
}
/// <summary>
/// Handles the stopping event generated by the MIDI clock.
/// </summary>
/// <param name="sender">
/// The MIDI clock responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void StoppingHandler(object sender, EventArgs e)
{
// Unlock the sequence so that it can not be modified.
Sequence.LockSequence(this, false);
player.AllSoundsOff();
seekPosition = false;
}
/// <summary>
/// Handles the position changed event generated by the MIDI clock.
/// </summary>
/// <param name="sender">
/// The MIDI clock responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void PositionChangedHandler(object sender, PositionChangedEventArgs e)
{
position = e.Position;
player.Seek(position);
}
/// <summary>
/// Handles the end of sequence reached event generated by the sequence
/// player.
/// </summary>
/// <param name="sender">
/// The sequence player responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void EndOfSequenceReachedHandler(object sender, EventArgs e)
{
clock.Stop();
}
/// <summary>
/// Handles and raises the tempo changed event.
/// </summary>
/// <param name="sender">
/// The tick generator responsible for the event.
/// </param>
/// <param name="e">
/// Information about the event.
/// </param>
private void OnTempoChanged(object sender, EventArgs e)
{
if(TempoChanged != null)
TempoChanged(this, EventArgs.Empty);
}
/// <summary>
/// Prepares the sequence player for playback.
/// </summary>
private void PreparePlayer()
{
player.EndOfSequenceReached -=
new EventHandler(EndOfSequenceReachedHandler);
player.Dispose();
player = new SequencePlayer(outDevice, tickGen, seq);
player.EndOfSequenceReached +=
new EventHandler(EndOfSequenceReachedHandler);
}
#endregion
#region Properties
/// <summary>
/// Gets or sets the input device's id.
/// </summary>
public int InputDeviceID
{
get
{
return inDevice.DeviceID;
}
set
{
Stop();
inDevice.Close();
inDevice.Open(value);
}
}
/// <summary>
/// Gets or sets the output device's id.
/// </summary>
public int OutputDeviceID
{
get
{
return outDevice.DeviceID;
}
set
{
Stop();
outDevice.Close();
outDevice.Open(value);
}
}
/// <summary>
/// Gets or sets a value indicating whether or not the master mode
/// is enabled.
/// </summary>
public bool MasterEnabled
{
get
{
return clock.MasterEnabled;
}
set
{
clock.MasterEnabled = value;
}
}
/// <summary>
/// Gets or sets a value indicating whether or not the slave mode is
/// enabled.
/// </summary>
public bool SlaveEnabled
{
get
{
return clock.SlaveEnabled;
}
set
{
clock.SlaveEnabled = value;
}
}
/// <summary>
/// Gets or sets the playback position in ticks.
/// </summary>
/// <remarks>
/// Attempting to set the position while the slave mode is enabled has
/// no effect.
/// </remarks>
public int Position
{
get
{
return position;
}
set
{
// Attempting to set the position in slave mode has no effect.
if(SlaveEnabled)
return;
if(value < 0)
throw new ArgumentOutOfRangeException("Positon", value,
"Position out of range.");
bool wasRunning = clock.IsRunning();
if(wasRunning)
clock.Stop();
position = value;
seekPosition = true;
if(wasRunning)
clock.Continue();
}
}
/// <summary>
/// Gets or sets the song position pointer.
/// </summary>
/// <remarks>
///
/// </remarks>
public int SongPositionPointer
{
get
{
SongPositionPointer spp =
new SongPositionPointer(tickGen.Ppqn);
spp.PositionInTicks = Position;
return spp.SongPosition;
}
set
{
// Attempting to set the position in slave mode has no effect.
if(SlaveEnabled)
return;
if(value < 0)
throw new ArgumentOutOfRangeException("SongPositionPointer",
value, "Song position pointer out of range.");
SongPositionPointer spp =
new SongPositionPointer(tickGen.Ppqn);
spp.SongPosition = value;
bool wasRunning = clock.IsRunning();
if(wasRunning)
clock.Stop();
position = spp.PositionInTicks;
seekPosition = true;
clock.SendSongPositionPointer(spp);
if(wasRunning)
clock.Continue();
}
}
/// <summary>
/// Gets or sets the sequence to play back.
/// </summary>
public Sequence Sequence
{
get
{
return seq;
}
set
{
Stop();
seq = value;
tickGen.Ppqn = seq.Division;
PreparePlayer();
sequenceVersion = seq.Version;
Position = 0;
}
}
/// <summary>
/// Gets or sets the tempo in microseconds.
/// </summary>
public int Tempo
{
get
{
return tickGen.Tempo;
}
set
{
tickGen.Tempo = value;
}
}
#endregion
#endregion
}
}
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Aside from dabbling in BASIC on his old Atari 1040ST years ago, Leslie's programming experience didn't really begin until he discovered the Internet in the late 90s. There he found a treasure trove of information about two of his favorite interests: MIDI and sound synthesis.
After spending a good deal of time calculating formulas he found on the Internet for creating new sounds by hand, he decided that an easier way would be to program the computer to do the work for him. This led him to learn C. He discovered that beyond using programming as a tool for synthesizing sound, he loved programming in and of itself.
Eventually he taught himself C++ and C#, and along the way he immersed himself in the ideas of object oriented programming. Like many of us, he gotten bitten by the design patterns bug and a copy of GOF is never far from his hands.
Now his primary interest is in creating a complete MIDI toolkit using the C# language. He hopes to create something that will become an indispensable tool for those wanting to write MIDI applications for the .NET framework.
Besides programming, his other interests are photography and playing his Les Paul guitars.
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