Platform_Sound_SoundStream Class Reference
[Platform]

Platform independent abstraction of a soundstream. More...

Inheritance diagram for Platform_Sound_SoundStream:

List of all members.

Public Member Functions
virtual	~Platform_Sound_SoundStream ()
virtual int	GetChannels ()=0
virtual int	GetFrequency ()=0
virtual int	GetBitsPerSample ()=0
virtual int	GetSize ()=0
virtual void	Play ()=0
virtual void	Stop ()=0
virtual int	GetPosition ()=0
virtual void	SetPosition (int position)=0
virtual float	GetVolume ()=0
virtual void	SetVolume (float level)=0
virtual void	ClearBuffer (int bufferOffset, int bytesToClear)=0
virtual void	CopySoundToBuffer (int bufferOffset, const void *soundData, int bytesToCopy)=0

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Detailed Description

Platform independent abstraction of a soundstream.

Author:

Mattias Gustavsson

Implements a sound channel for streaming sound. The idea is that you create a soundstream, fill it with the first bit of data from your sound, and then start playing it. You then monitor its current position, and when it's gone past half the buffer size, you fill in the first half of the buffer with more sound data, keep monitoring the buffer, and when the position have wrapped around, you fill the second half with more data, and so on. This means you can use and reuse soundstreams, and play both short and long sounds, or even music, with any soundstream.

Definition at line 27 of file Platform_Sound_SoundStream.h.

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Constructor & Destructor Documentation

virtual Platform_Sound_SoundStream::~Platform_Sound_SoundStream

(

)

[virtual]

Destructor

Definition at line 33 of file Platform_Sound_SoundStream.h.

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Member Function Documentation

virtual int Platform_Sound_SoundStream::GetChannels

(

)

[pure virtual]

Retrieves the number of channels this sound stream was created with.

Returns:

The number of channels, 1=mono, 2=stereo

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual int Platform_Sound_SoundStream::GetFrequency

(

)

[pure virtual]

Retrieves the frequency (samples per second) this sound stream was created with. Typical values for this is 11025 (11 kHz), 22050 (22 kHz) or 44100 (44 kHz, CD-quality).

Returns:

The number of samples per second

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual int Platform_Sound_SoundStream::GetBitsPerSample

(

)

[pure virtual]

Retrieves the number of bits per sample which this sound stream was created with. This is typically 8 or 16 bits.

Returns:

The number of bits per sample (typically 8 or 16)

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual int Platform_Sound_SoundStream::GetSize

(

)

[pure virtual]

Retrieves the number of bytes allocated for this sound streams buffer.

Returns:

The size of the sound stream buffer in bytes

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual void Platform_Sound_SoundStream::Play

(

)

[pure virtual]

Starts playing the sound stream, from whatever position it is currently at. The stream will keep playing and loop when it's reached the end, until the Stop method is called. The GetPosition method can be called to monitor the current position in the stream, and if looping is not desired, Stop should be called when the position have reached the end of the stream buffer.

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual void Platform_Sound_SoundStream::Stop

(

)

[pure virtual]

Pause the playback, and keeps the position so that the next call to Play will resume from the last point.

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual int Platform_Sound_SoundStream::GetPosition

(

)

[pure virtual]

Retrieves the current position in the sound stream buffer of the playback.

Returns:

The current position

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual void Platform_Sound_SoundStream::SetPosition

(

int

position

)

[pure virtual]

Sets the playback position. Must be in the range from 0 to the size of the sound stream buffer. There is no need to call Stop/Play for it to take effect.

Parameters:

position

The new position

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual float Platform_Sound_SoundStream::GetVolume

(

)

[pure virtual]

Retrieves the current volume level, in the range 0 to 1. This is a linear volume level value, where 0 is silent and 1 is full volume.

Returns:

The current volume

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual void Platform_Sound_SoundStream::SetVolume

(

float

level

)

[pure virtual]

Sets the current volume level, in the range 0 to 1. This is a linear volume level value, where 0 is silent and 1 is full volume.

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual void Platform_Sound_SoundStream::ClearBuffer	(	int	bufferOffset,
		int	bytesToClear
	)			[pure virtual]

Clears the specified part of the sound streams buffer. bufferOffset + bytesToClear should be less than the value returned by GetSize

Parameters:

	bufferOffset	Where in the sound stream buffer to clearing
	bytesToClear	Number of bytes to clear

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.

virtual void Platform_Sound_SoundStream::CopySoundToBuffer	(	int	bufferOffset,
		const void *	soundData,
		int	bytesToCopy
	)			[pure virtual]

Copies raw sound data to the sound streams buffer, starting at bufferOffset. The data is copied from the soundData pointer, for a total of bytesToCopy number of bytes. bufferOffset + bytesToClear should be less than the value returned by GetSize. The format of the data is interleaved raw sound samples, as specified by the combination of channels, frequency and bits per sample.

Parameters:

	bufferOffset	Where in the sound stream buffer to start copying data to
	soundData	Sound data to copy into the sound stream buffer
	bytesToCopy	Number of bytes to copy

Implemented in Platform_NULL_Sound_SoundStream, Platform_Win32_Sound_SoundStream_DSound, Platform_Win32_Sound_SoundStream_NoSound, and Platform_Win32_Sound_SoundStream_WMM.