SoundStream

Typedefs

typedef bool (*sfSoundStreamGetDataCallback)(sfSoundStreamChunk*, void*)

Type of the callback used to get a sound stream data.

typedef void (*sfSoundStreamSeekCallback)(sfTime, void*)

Type of the callback used to seek in a sound stream.

Functions

sfSoundStream *sfSoundStream_create(sfSoundStreamGetDataCallback onGetData, sfSoundStreamSeekCallback onSeek, unsigned int channelCount, unsigned int sampleRate, sfSoundChannel *channelMapData, size_t channelMapSize, void *userData)

Create a new sound stream.

Parameters:

  • onGetData – Function called when the stream needs more data (can’t be NULL)

  • onSeek – Function called when the stream seeks (can’t be NULL)

  • channelCount – Number of channels to use (1 = mono, 2 = stereo)

  • sampleRate – Sample rate of the sound (44100 = CD quality)

  • channelMapData – Pointer to the array of channel map data

  • channelMapSize – Size of channel map data array

  • userData – Data to pass to the callback functions

Returns:

A new sfSoundStream object

void sfSoundStream_destroy(const sfSoundStream *soundStream)

Destroy a sound stream.

Parameters:

  • soundStream – Sound stream to destroy

void sfSoundStream_play(sfSoundStream *soundStream)

Start or resume playing a sound stream.

This function starts the stream if it was stopped, resumes it if it was paused, and restarts it from beginning if it was it already playing. This function uses its own thread so that it doesn’t block the rest of the program while the music is played.

Parameters:

  • soundStream – Sound stream object

void sfSoundStream_pause(sfSoundStream *soundStream)

Pause a sound stream.

This function pauses the stream if it was playing, otherwise (stream already paused or stopped) it has no effect.

Parameters:

  • soundStream – Sound stream object

void sfSoundStream_stop(sfSoundStream *soundStream)

Stop playing a sound stream.

This function stops the stream if it was playing or paused, and does nothing if it was already stopped. It also resets the playing position (unlike sfSoundStream_pause).

Parameters:

  • soundStream – Sound stream object

sfSoundStatus sfSoundStream_getStatus(const sfSoundStream *soundStream)

Get the current status of a sound stream (stopped, paused, playing)

Parameters:

  • soundStream – Sound stream object

Returns:

Current status

unsigned int sfSoundStream_getChannelCount(const sfSoundStream *soundStream)

Return the number of channels of a sound stream.

1 channel means a mono sound, 2 means stereo, etc.

Parameters:

  • soundStream – Sound stream object

Returns:

Number of channels

unsigned int sfSoundStream_getSampleRate(const sfSoundStream *soundStream)

Get the sample rate of a sound stream.

The sample rate is the number of audio samples played per second. The higher, the better the quality.

Parameters:

  • soundStream – Sound stream object

Returns:

Sample rate, in number of samples per second

sfSoundChannel *sfSoundStream_getChannelMap(const sfSoundStream *soundStream, size_t *count)

Get the map of position in sample frame to sound channel.

This is used to map a sample in the sample stream to a position during spatialization.

Parameters:

  • soundStream – Sound stream object

  • count – Pointer to a variable that will be filled with the number of channels in the map

Returns:

Map of position in sample frame to sound channel

void sfSoundStream_setPitch(sfSoundStream *soundStream, float pitch)

Set the pitch of a sound stream.

The pitch represents the perceived fundamental frequency of a sound; thus you can make a stream more acute or grave by changing its pitch. A side effect of changing the pitch is to modify the playing speed of the stream as well. The default value for the pitch is 1.

Parameters:

  • soundStream – Sound stream object

  • pitch – New pitch to apply to the stream

void sfSoundStream_setPan(sfSoundStream *soundStream, float pan)

Set the pan of the sound.

Using panning, a mono sound can be panned between stereo channels. When the pan is set to -1, the sound is played only on the left channel, when the pan is set to +1, the sound is played only on the right channel.

Parameters:

  • soundStream – Sound stream object

  • pan – New pan to apply to the sound [-1, +1]

void sfSoundStream_setVolume(sfSoundStream *soundStream, float volume)

Set the volume of a sound stream.

The volume is a value between 0 (mute) and 100 (full volume). The default value for the volume is 100.

Parameters:

  • soundStream – Sound stream object

  • volume – Volume of the stream

void sfSoundStream_setSpatializationEnabled(sfSoundStream *soundStream, bool enabled)

Set whether spatialization of the sound is enabled.

Spatialization is the application of various effects to simulate a sound being emitted at a virtual position in 3D space and exhibiting various physical phenomena such as directional attenuation and doppler shift.

Parameters:

  • soundStream – Sound stream object

  • enabled – true to enable spatialization, false to disable

void sfSoundStream_setPosition(sfSoundStream *soundStream, sfVector3f position)

Set the 3D position of a sound stream in the audio scene.

Only streams with one channel (mono streams) can be spatialized. The default position of a stream is (0, 0, 0).

Parameters:

  • soundStream – Sound stream object

  • position – Position of the stream in the scene

void sfSoundStream_setDirection(sfSoundStream *soundStream, sfVector3f direction)

Set the 3D direction of the sound in the audio scene.

The direction defines where the sound source is facing in 3D space. It will affect how the sound is attenuated if facing away from the listener. The default direction of a sound is (0, 0, -1).

Parameters:

  • soundStream – Sound stream object

  • direction – Direction of the sound in the scene

void sfSoundStream_setCone(sfSoundStream *soundStream, sfSoundSourceCone cone)

Set the cone properties of the sound in the audio scene.

The cone defines how directional attenuation is applied. The default cone of a sound is (2 * PI, 2 * PI, 1).

Parameters:

  • soundStream – Sound stream object

  • cone – Cone properties of the sound in the scene

void sfSoundStream_setVelocity(sfSoundStream *soundStream, sfVector3f velocity)

Set the 3D velocity of the sound in the audio scene.

The velocity is used to determine how to doppler shift the sound. Sounds moving towards the listener will be perceived to have a higher pitch and sounds moving away from the listener will be perceived to have a lower pitch.

Parameters:

  • soundStream – Sound stream object

  • velocity – Velocity of the sound in the scene

void sfSoundStream_setDopplerFactor(sfSoundStream *soundStream, float factor)

Set the doppler factor of the sound.

The doppler factor determines how strong the doppler shift will be.

Parameters:

  • soundStream – Sound stream object

  • factor – New doppler factor to apply to the sound

void sfSoundStream_setDirectionalAttenuationFactor(sfSoundStream *soundStream, float factor)

Set the directional attenuation factor of the sound.

Depending on the virtual position of an output channel relative to the listener (such as in surround sound setups), sounds will be attenuated when emitting them from certain channels. This factor determines how strong the attenuation based on output channel position relative to the listener is.

Parameters:

  • soundStream – Sound stream object

  • factor – New directional attenuation factor to apply to the sound

void sfSoundStream_setRelativeToListener(sfSoundStream *soundStream, bool relative)

Make a sound stream’s position relative to the listener or absolute.

Making a stream relative to the listener will ensure that it will always be played the same way regardless the position of the listener. This can be useful for non-spatialized streams, streams that are produced by the listener, or streams attached to it. The default value is false (position is absolute).

Parameters:

  • soundStream – Sound stream object

  • relative – true to set the position relative, false to set it absolute

void sfSoundStream_setMinDistance(sfSoundStream *soundStream, float distance)

Set the minimum distance of a sound stream.

The “minimum distance” of a stream is the maximum distance at which it is heard at its maximum volume. Further than the minimum distance, it will start to fade out according to its attenuation factor. A value of 0 (“inside the head

of the listener”) is an invalid value and is forbidden. The default value of the minimum distance is 1.

Parameters:

  • soundStream – Sound stream object

  • distance – New minimum distance of the stream

void sfSoundStream_setMaxDistance(sfSoundStream *soundStream, float distance)

Set the maximum distance of the sound.

The “maximum distance” of a sound is the minimum distance at which it is heard at its minimum volume. Closer than the maximum distance, it will start to fade in according to its attenuation factor. The default value of the maximum distance is the maximum value a float can represent.

Parameters:

  • soundStream – Sound stream object

  • distance – New maximum distance of the sound

void sfSoundStream_setMinGain(sfSoundStream *soundStream, float gain)

Set the minimum gain of the sound.

When the sound is further away from the listener than the “maximum distance” the attenuated gain is clamped so it cannot go below the minimum gain value.

Parameters:

  • soundStream – Sound stream object

  • gain – New minimum gain of the sound

void sfSoundStream_setMaxGain(sfSoundStream *soundStream, float gain)

Set the maximum gain of the sound.

When the sound is closer from the listener than the “minimum distance” the attenuated gain is clamped so it cannot go above the maximum gain value.

Parameters:

  • soundStream – Sound stream object

  • gain – New maximum gain of the sound

void sfSoundStream_setAttenuation(sfSoundStream *soundStream, float attenuation)

Set the attenuation factor of a sound stream.

The attenuation is a multiplicative factor which makes the stream more or less loud according to its distance from the listener. An attenuation of 0 will produce a non-attenuated stream, i.e. its volume will always be the same whether it is heard from near or from far. On the other hand, an attenuation value such as 100 will make the stream fade out very quickly as it gets further from the listener. The default value of the attenuation is 1.

Parameters:

  • soundStream – Sound stream object

  • attenuation – New attenuation factor of the stream

void sfSoundStream_setPlayingOffset(sfSoundStream *soundStream, sfTime timeOffset)

Change the current playing position of a sound stream.

The playing position can be changed when the stream is either paused or playing.

Parameters:

  • soundStream – Sound stream object

  • timeOffset – New playing position

void sfSoundStream_setLooping(sfSoundStream *soundStream, bool loop)

Set whether or not a sound stream should loop after reaching the end.

If set, the stream will restart from beginning after reaching the end and so on, until it is stopped or sfSoundStream_setLooping(stream, false) is called. The default looping state for sound streams is false.

Parameters:

  • soundStream – Sound stream object

  • loop – true to play in loop, false to play once

float sfSoundStream_getPitch(const sfSoundStream *soundStream)

Get the pitch of a sound stream.

Parameters:

  • soundStream – Sound stream object

Returns:

Pitch of the stream

float sfSoundStream_getPan(const sfSoundStream *soundStream)

Get the pan of the sound.

Parameters:

  • soundStream – Sound stream object

Returns:

Pan of the sound

float sfSoundStream_getVolume(const sfSoundStream *soundStream)

Get the volume of a sound stream.

Parameters:

  • soundStream – Sound stream object

Returns:

Volume of the stream, in the range [0, 100]

bool sfSoundStream_isSpatializationEnabled(const sfSoundStream *soundStream)

Tell whether spatialization of the sound is enabled.

Parameters:

  • soundStream – Sound stream object

Returns:

true if spatialization is enabled, false if it’s disabled

sfVector3f sfSoundStream_getPosition(const sfSoundStream *soundStream)

Get the 3D position of a sound stream in the audio scene.

Parameters:

  • soundStream – Sound stream object

Returns:

Position of the stream in the world

sfVector3f sfSoundStream_getDirection(const sfSoundStream *soundStream)

Get the 3D direction of the sound in the audio scene.

Parameters:

  • soundStream – Sound stream object

Returns:

Direction of the sound

sfSoundSourceCone sfSoundStream_getCone(const sfSoundStream *soundStream)

Get the cone properties of the sound in the audio scene.

Parameters:

  • soundStream – Sound stream object

Returns:

Cone properties of the sound

sfVector3f sfSoundStream_getVelocity(const sfSoundStream *soundStream)

Get the 3D velocity of the sound in the audio scene.

Parameters:

  • soundStream – Sound stream object

Returns:

Velocity of the sound

float sfSoundStream_getDopplerFactor(const sfSoundStream *soundStream)

Get the doppler factor of the sound.

Parameters:

  • soundStream – Sound stream object

Returns:

Doppler factor of the sound

float sfSoundStream_getDirectionalAttenuationFactor(const sfSoundStream *soundStream)

Get the directional attenuation factor of the sound.

Parameters:

  • soundStream – Sound stream object

Returns:

Directional attenuation factor of the sound

bool sfSoundStream_isRelativeToListener(const sfSoundStream *soundStream)

Tell whether a sound stream’s position is relative to the listener or is absolute.

Parameters:

  • soundStream – Sound stream object

Returns:

true if the position is relative, false if it’s absolute

float sfSoundStream_getMinDistance(const sfSoundStream *soundStream)

Get the minimum distance of a sound stream.

Parameters:

  • soundStream – Sound stream object

Returns:

Minimum distance of the stream

float sfSoundStream_getMaxDistance(const sfSoundStream *soundStream)

Get the maximum distance of the sound.

Parameters:

  • soundStream – Sound stream object

Returns:

Maximum distance of the sound

float sfSoundStream_getMinGain(const sfSoundStream *soundStream)

Get the minimum gain of the sound.

Parameters:

  • soundStream – Sound stream object

Returns:

Minimum gain of the sound

float sfSoundStream_getMaxGain(const sfSoundStream *soundStream)

Get the maximum gain of the sound.

Parameters:

  • soundStream – Sound stream object

Returns:

Maximum gain of the sound

float sfSoundStream_getAttenuation(const sfSoundStream *soundStream)

Get the attenuation factor of a sound stream.

Parameters:

  • soundStream – Sound stream object

Returns:

Attenuation factor of the stream

bool sfSoundStream_isLooping(const sfSoundStream *soundStream)

Tell whether or not a sound stream is in loop mode.

Parameters:

  • soundStream – Sound stream object

Returns:

true if the music is looping, false otherwise

void sfSoundStream_setEffectProcessor(sfSoundStream *soundStream, sfEffectProcessor effectProcessor)

Set the effect processor to be applied to the sound.

The effect processor is a callable that will be called with sound data to be processed.

Parameters:

  • soundStream – Sound stream object

  • effectProcessor – The effect processor to attach to this sound, attach an empty processor to disable processing

sfTime sfSoundStream_getPlayingOffset(const sfSoundStream *soundStream)

Get the current playing position of a sound stream.

Parameters:

  • soundStream – Sound stream object

Returns:

Current playing position

struct sfSoundStreamChunk
#include <SoundStream.h>

defines the data to fill by the OnGetData callback

Public Members

int16_t *samples

Pointer to the audio samples.

unsigned int sampleCount

Number of samples pointed by Samples.