Copyright ã1995 by NeXT Computer, Inc.  All Rights Reserved.

NXSoundParameters

Inherits From:	Object

Conforms To:	NXSoundParameters (the protocol)

Declared In:	soundkit/NXSoundParameters.h

Class Description

The NXSoundParameters class provides an implementation of the methods defined by the NXSoundParameters protocol.  This implementation lets you create objects that can be passed as NXSoundParameters-conforming arguments to methods, primarily those defined in NXSoundDevice and NXSoundStream, that require such conformance.

Most of the functionality provided by the NXSoundParameters class is expressed by the NXSoundParameters protocol; see the protocol specification for an explanation of its methods.  

Instance Variables

None declared in this class.

Adopted Protocols

NXSoundParameters	- boolValueForParameter:
- floatValueForParameter:
- getParameters:count:
- getValues:count:forParameter:
- intValueForParameter:
- isParameterPresent:
- removeParameter:
- setParameter:toBool:
- setParameter:toFloat:
- setParameter:toInt:

Method Types

Initializing and freeing	- init
- initFromSound:
- initFromSoundStruct:
- free

Broadcasting information	- configureSoundStruct:

Querying parameters	+ localizedNameForParameter:

Class Methods

localizedNameForParameter:

+ (const char *)localizedNameForParameter:(NXSoundParameterTag)ptag 

Returns the string name of the parameter key or value that's represented by the parameter tag argument.  The name can be used, for example, as the title of an element in the user interface; its importance doesn't rise much above this utility.  

A list of parameter tags provided by the Sound Kit is given in the section ªTypes and Constants.º  If an unrecognized tag is passed to this method, the (localized) string equivalent to ªUnknown parameterº is returned.

Instance Methods

configureSoundStruct:

- (void)configureSoundStruct:(SNDSoundStruct *)soundStruct 

Sets the sound format of the SNDSoundStruct argument by copying the values of the appropriate parameters from the NXSoundParameters object.  If a candidate parameter hasn't been set in the object, the sound structure maintains its current value for the analogous attributeÐin other words, a non-existent parameter won't overwrite a value in the structure.

The table below shows the correspondences between sound structure fields and parameters:

Structure Field	Parameter

samplingRate	NX_SoundStreamSamplingRate
channelCount	NX_SoundStreamChannelCount
dataFormat	NX_SoundStreamDataEncoding

The SNDSoundStruct structure is described in the section ªTypes and Constants.º

free

- free

Frees the object and its table of parameters.

init

- init

Initializes and returns an NXSoundParameters object.  The object's parameter table is empty immediately after initialization.

See also:  - initFromSound:, - initFromSoundStruct:

initFromSound:

- initFromSound:aSound 

Initializes and returns an NXSoundParameters object that contains parameters that take their values from the given Sound object.  The values that are applied to the parameters are taken from the Sound object's SNDSoundStruct structure; the correspondences between structure fields and parameters is given in the initFromSoundStruct: method.

See also:  - init, - initFromSoundStruct:

initFromSoundStruct:

- initFromSoundStruct:(SNDSoundStruct *)soundStruct 

Initializes and returns an NXSoundParameters object that contains parameters that take their values from the given SNDSoundStruct, as noted below:

Parameter	Structure Field

NX_SoundStreamSamplingRate	samplingRate	
NX_SoundStreamChannelCount	channelCount	
NX_SoundStreamDataEncoding	dataFormat