This class provides easy sample loading, device enumeration and error retrieval. More...

#include <al_context.h>

Public Member Functions
	OALContext (const std::string &device_name)
	Construct context, connect to output device and make context current.

	OALContext (const OALContext &other)=delete

	OALContext (OALContext &&other)=default

OALContext &	operator= (const OALContext &other)=delete

OALContext &	operator= (OALContext &&other)=default

	~OALContext ()
	detach context from output device and destruct

std::string	get_device_name () const
	return device name of contexts device

void	make_current ()
	in case of multiple contexts, this makes this context current

void	create_buffer (const std::string &symbolic_name, const OALSoundFormat &format, const void *data, size_t data_length)
	create a named sound buffer from a format descriptor and a data buffer of given length in bytes

void	load_sample (std::string filepath, std::string symbolic_name="")
	Loads a sound into the internal buffer list.

void	load_sample (std::string symbolic_name, const void *data, size_t data_length)
	Loads a sound into the internal buffer list.

void	load_samples (std::string folder, bool recursive=false)
	Loads all audio files in a folder into the internal buffer list.

ALuint	get_buffer_id (std::string sound_name) const
	Gets the buffer identifier for the symbolic name.

std::string	get_error_string ()
	Returns the last error from the OpenAL context.

bool	is_no_error ()
	Determines if there were any errors since last call.

void	set_HRTF (bool active)
	Toggles the OpenAL output mode to use HRTF.

ALCdevice *	get_native_device ()
	Gets the native device handle for direct OpenAL calls.

ALCcontext *	get_native_context ()
	Gets the native context handle for direct OpenAL calls.

Static Public Member Functions
static std::vector< std::string >	enumerate_devices ()
	Enumerate audio output devices available on system.

static std::string	get_default_device_name ()
	returns name of system's default device

static bool	decode_sound_file (const void *data, size_t data_length, OALSoundFormat &format, std::vector< int16_t > &memory_buffer)
	decode sound file that is already in memory data with data_length bytes to a newly constructed memory buffer

static bool	load_sound_file (const std::string &filepath, OALSoundFormat &format, std::vector< int16_t > &memory_buffer)
	load and decode sound file to newly constructed memory buffer

Detailed Description

This class provides easy sample loading, device enumeration and error retrieval.

Definition at line 39 of file al_context.h.

Constructor & Destructor Documentation

◆ OALContext()

cgv::audio::OALContext::OALContext ( const std::string & device_name )

explicit

Construct context, connect to output device and make context current.

Parameters

[in] device The OpenAL device string identifier

See also: enumerate_devices()

Definition at line 41 of file al_context.cxx.

◆ ~OALContext()

cgv::audio::OALContext::~OALContext ( )

detach context from output device and destruct

Definition at line 58 of file al_context.cxx.

Member Function Documentation

◆ create_buffer()

void cgv::audio::OALContext::create_buffer	(	const std::string &	symbolic_name,
		const OALSoundFormat &	format,
		const void *	data,
		size_t	data_length
	)

create a named sound buffer from a format descriptor and a data buffer of given length in bytes

Definition at line 149 of file al_context.cxx.

Referenced by load_sample(), and load_sample().

◆ decode_sound_file()

bool cgv::audio::OALContext::decode_sound_file	(	const void *	data,
		size_t	data_length,
		OALSoundFormat &	format,
		std::vector< int16_t > &	memory_buffer
	)

static

decode sound file that is already in memory data with data_length bytes to a newly constructed memory buffer

Definition at line 92 of file al_context.cxx.

Referenced by load_sample().

◆ enumerate_devices()

std::vector< std::string > cgv::audio::OALContext::enumerate_devices ( )

static

Enumerate audio output devices available on system.

Returns: vector of device names which can be passed to constructor

See also: explicit OALContext(std::string)

Definition at line 25 of file al_context.cxx.

◆ get_buffer_id()

ALuint cgv::audio::OALContext::get_buffer_id ( std::string sound_name ) const

Gets the buffer identifier for the symbolic name.

Parameters

[in] sound_name The symbolic sound name of the buffer.

Returns: The buffer ID as used by OpenAL.

See also: load_sample(); load_samples()

Definition at line 215 of file al_context.cxx.

◆ get_default_device_name()

std::string cgv::audio::OALContext::get_default_device_name ( )

static

returns name of system's default device

Definition at line 19 of file al_context.cxx.

◆ get_device_name()

std::string cgv::audio::OALContext::get_device_name ( ) const

return device name of contexts device

Definition at line 53 of file al_context.cxx.

◆ get_error_string()

std::string cgv::audio::OALContext::get_error_string ( )

Returns the last error from the OpenAL context.

Returns: The error string.

Warning: This function call clears the last error in the OpenAL context.

See also: is_no_error()

Definition at line 220 of file al_context.cxx.

◆ get_native_context()

ALCcontext * cgv::audio::OALContext::get_native_context ( )

Gets the native context handle for direct OpenAL calls.

Returns: The native OpenAL context handle.

Definition at line 235 of file al_context.cxx.

Referenced by cgv::audio::OALSource::append_sound(), and cgv::audio::OALSource::init().

◆ get_native_device()

ALCdevice * cgv::audio::OALContext::get_native_device ( )

Gets the native device handle for direct OpenAL calls.

Returns: The native OpenAL device handle.

Definition at line 233 of file al_context.cxx.

Referenced by set_HRTF().

◆ is_no_error()

bool cgv::audio::OALContext::is_no_error ( )

Determines if there were any errors since last call.

Returns: True if no errors were encountered, False otherwise.

Warning: This function call clears the last error in the OpenAL context.

See also: get_error_string()

Definition at line 221 of file al_context.cxx.

Referenced by cgv::audio::OALSource::init().

◆ load_sample() [1/2]

void cgv::audio::OALContext::load_sample	(	std::string	filepath,
		std::string	symbolic_name = `""`
	)

Loads a sound into the internal buffer list.

Parameters

[in]	filepath	The filepath to the sample file
[in]	symbolic_name	Sound is named by file stem or if given this parameter

Remarks: The supported filetypes are .WAV, .AIFF, .FLAC, etc. For detailed information visit http://www.mega-nerd.com/libsndfile/

Definition at line 169 of file al_context.cxx.

References create_buffer(), and load_sound_file().

Referenced by load_samples().

◆ load_sample() [2/2]

void cgv::audio::OALContext::load_sample	(	std::string	symbolic_name,
		const void *	data,
		size_t	data_length
	)

Loads a sound into the internal buffer list.

Parameters

[in]	symbolic_name	The symbolic name used as key for later retrieval
[in]	data	A pointer to the first sample of the audio data
[in]	data_length	The length of the audio data buffer in bytes

Remarks: This function is implemented via virtual IO on top of the supplied buffer. Therefore the supplied buffer needs to be an in memory copy of a ordinary audio file (for example contain the necessary .WAV headers etc.).; Each file will be transformed into a buffer ID with the filename stem as symbolic key. For example: ./sounds/Wind.wav will have the key "Wind".

Definition at line 184 of file al_context.cxx.

References create_buffer(), and decode_sound_file().

◆ load_samples()

void cgv::audio::OALContext::load_samples	(	std::string	folder,
		bool	recursive = `false`
	)

Loads all audio files in a folder into the internal buffer list.

Parameters

[in]	folder	The path to the folder
[in]	recursive	True if subfolders should be traversed as well, False otherwise.

Remarks: This function is a convenience wrapper around the tedious process of reading all files in a folder and uploading each to a buffer.

See also: load_sample(std::string)

Definition at line 192 of file al_context.cxx.

References load_sample().

◆ load_sound_file()

bool cgv::audio::OALContext::load_sound_file	(	const std::string &	filepath,
		OALSoundFormat &	format,
		std::vector< int16_t > &	memory_buffer
	)

static

load and decode sound file to newly constructed memory buffer

Definition at line 137 of file al_context.cxx.

Referenced by load_sample().

◆ make_current()

void cgv::audio::OALContext::make_current ( )

in case of multiple contexts, this makes this context current

Definition at line 49 of file al_context.cxx.

◆ set_HRTF()

void cgv::audio::OALContext::set_HRTF ( bool active )

Toggles the OpenAL output mode to use HRTF.

Parameters

[in] active True if the output should be filtered with a head related transfer function, False otherwise.

Remarks: HRTFs improve the perceived localization of sounds in the scene. Therefore it is advisable to enable HRTF output with headphones. For loudspeakers however this should be disabled as the users head already has a specific HRTF.

Definition at line 222 of file al_context.cxx.

References get_native_device().

The documentation for this class was generated from the following files:

libs/cgv_oal/al_context.h
libs/cgv_oal/al_context.cxx

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ OALContext()

◆ ~OALContext()

Member Function Documentation

◆ create_buffer()

◆ decode_sound_file()

◆ enumerate_devices()

◆ get_buffer_id()

◆ get_default_device_name()

◆ get_device_name()

◆ get_error_string()

◆ get_native_context()

◆ get_native_device()

◆ is_no_error()

◆ load_sample() [1/2]

◆ load_sample() [2/2]

◆ load_samples()

◆ load_sound_file()

◆ make_current()

◆ set_HRTF()