OpenTK.Audio.AudioContext Class Reference

Provides methods to instantiate, use and destroy an audio context for playback. Static methods are provided to list available devices known by the driver. More...

List of all members.

Public Types
enum	MaxAuxiliarySends { UseDriverDefault = 0, One = 1, Two = 2, Three = 3, Four = 4 }
	May be passed at context construction time to indicate the number of desired auxiliary effect slot sends per source. More...
Public Member Functions
	AudioContext ()
	Constructs a new AudioContext, using the default audio device.
	AudioContext (string device)
	Constructs a new AudioContext instance.
	AudioContext (string device, int freq)
	Constructs a new AudioContext, using the specified audio device and device parameters.
	AudioContext (string device, int freq, int refresh)
	Constructs a new AudioContext, using the specified audio device and device parameters.
	AudioContext (string device, int freq, int refresh, bool sync)
	Constructs a new AudioContext, using the specified audio device and device parameters.
	AudioContext (string device, int freq, int refresh, bool sync, bool enableEfx)
	Creates the audio context using the specified device and device parameters.
	AudioContext (string device, int freq, int refresh, bool sync, bool enableEfx, MaxAuxiliarySends efxMaxAuxSends)
	Creates the audio context using the specified device and device parameters.
void	CheckErrors ()
	Checks for ALC error conditions.
void	MakeCurrent ()
	Makes the AudioContext current in the calling thread.
void	Process ()
	Processes queued audio events.
void	Suspend ()
	Suspends processing of audio events.
bool	SupportsExtension (string extension)
	Checks whether the specified OpenAL extension is supported.
void	Dispose ()
	Disposes of the AudioContext, cleaning up all resources consumed by it.
override int	GetHashCode ()
	Calculates the hash code for this instance.
override bool	Equals (object obj)
	Compares this instance with another.
override string	ToString ()
	Returns a System.String that desrcibes this instance.
Properties
AlcError	CurrentError `[get]`
	Returns the ALC error code for this instance.
bool	IsProcessing `[get, set]`
	Gets a System.Boolean indicating whether the AudioContext is currently processing audio events.
bool	IsSynchronized `[get, set]`
	Gets a System.Boolean indicating whether the AudioContext is synchronized.
string	CurrentDevice `[get]`
	Gets a System.String with the name of the device used in this context.
static AudioContext	CurrentContext `[get]`
	Gets the OpenTK.Audio.AudioContext which is current in the application.
static IList< string >	AvailableDevices `[get]`
	Returns a list of strings containing all known playback devices.
static string	DefaultDevice `[get]`
	Returns the name of the device that will be used as playback default.

Detailed Description

Provides methods to instantiate, use and destroy an audio context for playback. Static methods are provided to list available devices known by the driver.

Definition at line 42 of file AudioContext.cs.

Member Enumeration Documentation

enum OpenTK::Audio::AudioContext::MaxAuxiliarySends

May be passed at context construction time to indicate the number of desired auxiliary effect slot sends per source.

Enumerator:

UseDriverDefault	Will chose a reliably working parameter.
One	One send per source.
Two	Two sends per source.
Three	Three sends per source.
Four	Four sends per source.

Definition at line 212 of file AudioContext.cs.

00212                                      :int
00213         {
00215             UseDriverDefault = 0,
00217             One = 1,
00219             Two = 2,
00221             Three = 3,
00223             Four = 4,
00224         }

Constructor & Destructor Documentation

OpenTK.Audio.AudioContext.AudioContext ( )

Constructs a new AudioContext, using the default audio device.

Definition at line 77 of file AudioContext.cs.

00078             : this(null, 0, 0, false, true, MaxAuxiliarySends.UseDriverDefault) { }

OpenTK.Audio.AudioContext.AudioContext ( string device )

Constructs a new AudioContext instance.

Parameters:

device

The device name that will host this instance.

Definition at line 88 of file AudioContext.cs.

00088 : this(device, 0, 0, false, true, MaxAuxiliarySends.UseDriverDefault) { }

OpenTK.Audio.AudioContext.AudioContext	(	string	device,
		int	freq
	)

Constructs a new AudioContext, using the specified audio device and device parameters.

Parameters:

	device	The name of the audio device to use.
	freq	Frequency for mixing output buffer, in units of Hz. Pass 0 for driver default.

Use AudioContext.AvailableDevices to obtain a list of all available audio devices. devices.

Definition at line 101 of file AudioContext.cs.

00101 : this(device, freq, 0, false, true, MaxAuxiliarySends.UseDriverDefault) { }

OpenTK.Audio.AudioContext.AudioContext	(	string	device,
		int	freq,
		int	refresh
	)

Constructs a new AudioContext, using the specified audio device and device parameters.

Parameters:

	device	The name of the audio device to use.
	freq	Frequency for mixing output buffer, in units of Hz. Pass 0 for driver default.
	refresh	Refresh intervals, in units of Hz. Pass 0 for driver default.

Use AudioContext.AvailableDevices to obtain a list of all available audio devices. devices.

Definition at line 115 of file AudioContext.cs.

00116             : this(device, freq, refresh, false, true, MaxAuxiliarySends.UseDriverDefault) { }

OpenTK.Audio.AudioContext.AudioContext	(	string	device,
		int	freq,
		int	refresh,
		bool	sync
	)

Constructs a new AudioContext, using the specified audio device and device parameters.

Parameters:

	device	The name of the audio device to use.
	freq	Frequency for mixing output buffer, in units of Hz. Pass 0 for driver default.
	refresh	Refresh intervals, in units of Hz. Pass 0 for driver default.
	sync	Flag, indicating a synchronous context.

Use AudioContext.AvailableDevices to obtain a list of all available audio devices. devices.

Definition at line 131 of file AudioContext.cs.

00132             : this(AudioDeviceEnumerator.AvailablePlaybackDevices[0], freq, refresh, sync, true) { }

OpenTK.Audio.AudioContext.AudioContext	(	string	device,
		int	freq,
		int	refresh,
		bool	sync,
		bool	enableEfx
	)

Creates the audio context using the specified device and device parameters.

Parameters:

	device	The device descriptor obtained through AudioContext.AvailableDevices.
	freq	Frequency for mixing output buffer, in units of Hz. Pass 0 for driver default.
	refresh	Refresh intervals, in units of Hz. Pass 0 for driver default.
	sync	Flag, indicating a synchronous context.
	enableEfx	Indicates whether the EFX extension should be initialized, if present.

Exceptions:

	ArgumentNullException	Occurs when the device string is invalid.
	ArgumentOutOfRangeException	Occurs when a specified parameter is invalid.
	AudioDeviceException	Occurs when the specified device is not available, or is in use by another program.
	AudioContextException	Occurs when an audio context could not be created with the specified parameters.
	NotSupportedException	Occurs when an AudioContext already exists.

For maximum compatibility, you are strongly recommended to use the default constructor.

Multiple AudioContexts are not supported at this point.

The number of auxilliary EFX sends depends on the audio hardware and drivers. Most Realtek devices, as well as the Creative SB Live!, support 1 auxilliary send. Creative's Audigy and X-Fi series support 4 sends. Values higher than supported will be clamped by the driver.

Definition at line 163 of file AudioContext.cs.

00164         {
00165             CreateContext(device, freq, refresh, sync, enableEfx, MaxAuxiliarySends.UseDriverDefault);
00166         }

OpenTK.Audio.AudioContext.AudioContext	(	string	device,
		int	freq,
		int	refresh,
		bool	sync,
		bool	enableEfx,
		MaxAuxiliarySends	efxMaxAuxSends
	)

Creates the audio context using the specified device and device parameters.

Parameters:

	device	The device descriptor obtained through AudioContext.AvailableDevices.
	freq	Frequency for mixing output buffer, in units of Hz. Pass 0 for driver default.
	refresh	Refresh intervals, in units of Hz. Pass 0 for driver default.
	sync	Flag, indicating a synchronous context.
	enableEfx	Indicates whether the EFX extension should be initialized, if present.
	efxMaxAuxSends	Requires EFX enabled. The number of desired Auxiliary Sends per source.

Exceptions:

	ArgumentNullException	Occurs when the device string is invalid.
	ArgumentOutOfRangeException	Occurs when a specified parameter is invalid.
	AudioDeviceException	Occurs when the specified device is not available, or is in use by another program.
	AudioContextException	Occurs when an audio context could not be created with the specified parameters.
	NotSupportedException	Occurs when an AudioContext already exists.

For maximum compatibility, you are strongly recommended to use the default constructor.

Multiple AudioContexts are not supported at this point.

The number of auxilliary EFX sends depends on the audio hardware and drivers. Most Realtek devices, as well as the Creative SB Live!, support 1 auxilliary send. Creative's Audigy and X-Fi series support 4 sends. Values higher than supported will be clamped by the driver.

Definition at line 198 of file AudioContext.cs.

00199         {
00200             CreateContext(device, freq, refresh, sync, enableEfx, efxMaxAuxSends);
00201         }

Member Function Documentation

void OpenTK.Audio.AudioContext.CheckErrors ( )

Checks for ALC error conditions.

Exceptions:

	OutOfMemoryException	Raised when an out of memory error is detected.
	AudioValueException	Raised when an invalid value is detected.
	AudioDeviceException	Raised when an invalid device is detected.
	AudioContextException	Raised when an invalid context is detected.

Definition at line 434 of file AudioContext.cs.

00435         {
00436             if (disposed)
00437                 throw new ObjectDisposedException(this.GetType().FullName);
00438 
00439             new AudioDeviceErrorChecker(device_handle).Dispose();
00440         }

void OpenTK.Audio.AudioContext.Dispose ( )

Disposes of the AudioContext, cleaning up all resources consumed by it.

Definition at line 698 of file AudioContext.cs.

00699         {
00700             this.Dispose(true);
00701             GC.SuppressFinalize(this);
00702         }

override bool OpenTK.Audio.AudioContext.Equals ( object obj )

Compares this instance with another.

Parameters:

obj

The instance to compare to.

Returns:: True, if obj refers to this instance; false otherwise.

Definition at line 753 of file AudioContext.cs.

00754         {
00755             return base.Equals(obj);
00756         }

override int OpenTK.Audio.AudioContext.GetHashCode ( )

Calculates the hash code for this instance.

Returns:

Definition at line 743 of file AudioContext.cs.

00744         {
00745             return base.GetHashCode();
00746         }

void OpenTK.Audio.AudioContext.MakeCurrent ( )

Makes the AudioContext current in the calling thread.

Exceptions:

	ObjectDisposedException	Occurs if this function is called after the AudioContext has been disposed.
	AudioContextException	Occurs when the AudioContext could not be made current.

Only one AudioContext can be current in the application at any time, regardless of the number of threads.

Definition at line 475 of file AudioContext.cs.

00476         {
00477             if (disposed)
00478                 throw new ObjectDisposedException(this.GetType().FullName);
00479 
00480             AudioContext.MakeCurrent(this);
00481         }

void OpenTK.Audio.AudioContext.Process ( )

Processes queued audio events.

If AudioContext.IsSynchronized is true, this function will resume the internal audio processing thread. If AudioContext.IsSynchronized is false, you will need to call this function multiple times per second to process audio events.

In some implementations this function may have no effect.

Exceptions:

ObjectDisposedException

Occurs when this function is called after the AudioContext had been disposed.

See also:: Suspend, IsProcessing, IsSynchronized

Definition at line 548 of file AudioContext.cs.

00549         {
00550             if (disposed)
00551                 throw new ObjectDisposedException(this.GetType().FullName);
00552 
00553             Alc.ProcessContext(this.context_handle);
00554             IsProcessing = true;
00555         }

bool OpenTK.Audio.AudioContext.SupportsExtension ( string extension )

Checks whether the specified OpenAL extension is supported.

Parameters:

extension

The name of the extension to check (e.g. "ALC_EXT_EFX").

Returns:: true if the extension is supported; false otherwise.

Definition at line 599 of file AudioContext.cs.

00600         {
00601             if (disposed)
00602                 throw new ObjectDisposedException(this.GetType().FullName);
00603 
00604             return Alc.IsExtensionPresent(this.Device, extension);
00605         }

void OpenTK.Audio.AudioContext.Suspend ( )

Suspends processing of audio events.

To avoid audio artifacts when calling this function, set audio gain to zero before suspending an AudioContext.

In some implementations, it can be faster to suspend processing before changing AudioContext state.

In some implementations this function may have no effect.

Exceptions:

ObjectDisposedException

Occurs when this function is called after the AudioContext had been disposed.

See also:: Process, IsProcessing, IsSynchronized

Definition at line 581 of file AudioContext.cs.

00582         {
00583             if (disposed)
00584                 throw new ObjectDisposedException(this.GetType().FullName);
00585 
00586             Alc.SuspendContext(this.context_handle);
00587             IsProcessing = false;
00588         }

override string OpenTK.Audio.AudioContext.ToString ( )

Returns a System.String that desrcibes this instance.

Returns:: A System.String that desrcibes this instance.

Definition at line 762 of file AudioContext.cs.

00763         {
00764             return String.Format("{0} (handle: {1}, device: {2})",
00765                                  this.device_name, this.context_handle, this.device_handle);
00766         }

Property Documentation

IList<string> OpenTK.Audio.AudioContext.AvailableDevices [static, get]

Returns a list of strings containing all known playback devices.

Definition at line 668 of file AudioContext.cs.

AudioContext OpenTK.Audio.AudioContext.CurrentContext [static, get]

Gets the OpenTK.Audio.AudioContext which is current in the application.

Only one AudioContext can be current in the application at any time, regardless of the number of threads.

Definition at line 641 of file AudioContext.cs.

string OpenTK.Audio.AudioContext.CurrentDevice [get]

Gets a System.String with the name of the device used in this context.

Definition at line 615 of file AudioContext.cs.

AlcError OpenTK.Audio.AudioContext.CurrentError [get]

Returns the ALC error code for this instance.

Definition at line 450 of file AudioContext.cs.

string OpenTK.Audio.AudioContext.DefaultDevice [static, get]

Returns the name of the device that will be used as playback default.

Definition at line 682 of file AudioContext.cs.

bool OpenTK.Audio.AudioContext.IsProcessing [get, set]

Gets a System.Boolean indicating whether the AudioContext is currently processing audio events.

See also:: Process, Suspend

Definition at line 494 of file AudioContext.cs.

bool OpenTK.Audio.AudioContext.IsSynchronized [get, set]

Gets a System.Boolean indicating whether the AudioContext is synchronized.

See also:: Process

Definition at line 515 of file AudioContext.cs.

OpenTK.Audio.AudioContext Class Reference

Public Types

Public Member Functions

Properties

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Property Documentation