lg_audio.c File Reference

Functions
int	lg_init_audio_to_defaults ()
int	lg_init_audio (int freq, uint16_t format, int n_channels, int buffer_size)
void	lg_free_audio ()
int	lg_load_play_music (const char *file_name, int loops)
zboolean	lg_music_is_playing ()
void	lg_pause_music ()
void	lg_resume_music ()
void	lg_stop_music ()
void	lg_free_music ()
LG_Sound *	lg_sound_new (const char *file_name)
void	lg_disable_cant_play_audio_file ()
void	lg_enable_cant_play_audio_file ()
int	lg_sound_play (lg_play_mode mode, LG_Sound *sound)
zboolean	lg_sound_is_playing (LG_Sound *sound)
void	lg_sound_channel_set_volume (LG_Sound *sound, float v)
float	lg_sound_channel_get_volume (LG_Sound *sound)
void	lg_sound_free (LG_Sound *sound)
void	lg_audio_set_global_volume (float v)
void	lg_audio_set_music_volume (float v)
void	lg_audio_set_sounds_volume (float v)
void	lg_audio_pause ()
void	lg_audio_resume ()
void	lg_audio_stop ()
int	lg_audio_get_n_channels ()

Detailed Description

 === SDL2 Mixer audio system ===

 Unlike sounds, only *one* music playing at a time

 Should maybe use a linked list or sth, to get some kind of sound pool

Function Documentation

lg_init_audio_to_defaults()

int lg_init_audio_to_defaults

(

)

Init SDL2 Mixer audio system (using default values)

Returns

LG_OK if OK

lg_init_audio()

int lg_init_audio	(	int	freq,
		uint16_t	format,
		int	n_channels,
		int	buffer_size
	)

Init SDL2 Mixer audio system

See: https://wiki.libsdl.org/SDL2_mixer/Mix_OpenAudio

Parameters

freq	Frequency to playback audio (in Hz)
format	Audio format (one of SDL's AUDIO_* values)
n_channels	Num of audio channels
buffer_size	Size of audio buffer

Returns

LG_OK if OK

lg_free_audio()

void lg_free_audio

(

)

Free SDL2 Mixer audio system resources

This func is always called by lg_quit()

lg_load_play_music()

int lg_load_play_music	(	const char *	file_name,
		int	loops
	)

Load and play music

Parameters

file_name	A music file in the 'music' assets (don't use lg_mus() as it's already used internally)
loops	Number of times to play, -1 = don't stop

Returns

LG_OK if OK

lg_music_is_playing()

zboolean lg_music_is_playing

(

)

Check state of music playing

Returns

TRUE if music is playing, FALSE otherwise

lg_pause_music()

void lg_pause_music

(

)

Pause music playing

lg_resume_music()

void lg_resume_music

(

)

Resume music playing

lg_stop_music()

void lg_stop_music

(

)

Stop music playing

lg_free_music()

void lg_free_music

(

)

Free music

This func is always called by lg_quit()

lg_sound_new()

LG_Sound* lg_sound_new

(

const char *

file_name

)

Load a new sound

Parameters

file_name

A sound file in the 'sounds' assets (don't use lg_snd() as it's already used internally)

Returns

A new LG_Sound instance if OK, NULL on error

lg_disable_cant_play_audio_file()

void lg_disable_cant_play_audio_file

(

)

Disable "Can't play audio file" logging - can be quite verbose if some latency issues

lg_enable_cant_play_audio_file()

void lg_enable_cant_play_audio_file

(

)

Enable "Can't play audio file" logging - can be quite verbose if some latency issues

This is the default state

lg_sound_play()

int lg_sound_play	(	lg_play_mode	mode,
		LG_Sound *	sound
	)

Play sound

Example use of lg_sound_*() funcs in file level_1.c:

// Global vars
LG_Sound *jet_engine_starting, *jet_engine, *contact;
 
static void init_level1_sounds()
{
   jet_engine_starting = lg_sound_new("jet_engine_starting.ogg");
   jet_engine = lg_sound_new("jet_engine.ogg");
   contact = lg_sound_new("contact.ogg");
}
 
static void free_level1_sounds()
{
   lg_sound_free(jet_engine_starting);
   lg_sound_free(jet_engine);
   lg_sound_free(contact);
}
 
int level_1()
{
   // ...
   init_level1_sounds();
   // ...
   while (1) {
           // ...
           lg_sound_play(LG_PLAY, jet_engine_starting);
           // ...
           lg_sound_play(LG_STOP, jet_engine_starting);
           lg_sound_play(LG_REPEAT, jet_engine);
           // ...
           if (lg_bboxes_collide(&bbox_jet, &bbox1)) {
                   lg_sound_play(LG_PLAY, contact);
           // ...
   }
   // ...
   free_level1_sounds();

Parameters

mode	A lg_play_mode, one of LG_PLAY, LG_REPEAT, LG_WAIT, LG_STOP, LG_PAUSE, LG_RESUME
sound	A LG_Sound instance

Returns

LG_OK if OK

lg_sound_is_playing()

zboolean lg_sound_is_playing

(

LG_Sound *

sound

)

Check state of sound playing

Parameters

sound

A LG_Sound instance

Returns

TRUE if sound is playing, FALSE otherwise

lg_sound_channel_set_volume()

void lg_sound_channel_set_volume	(	LG_Sound *	sound,
		float	v
	)

Set volume of specific sound->channel

=== EXPERIMENTAL ===

Parameters

sound

A LG_Sound instance

Returns

Volume in range [0.0, 1.0]

lg_sound_channel_get_volume()

float lg_sound_channel_get_volume

(

LG_Sound *

sound

)

Get volume of specific sound->channel

=== EXPERIMENTAL ===

Parameters

sound

A LG_Sound instance

Returns

Volume in range [0.0, 1.0], -1 on error

lg_sound_free()

void lg_sound_free

(

LG_Sound *

sound

)

Free sound

Parameters

sound

A LG_Sound instance

lg_audio_set_global_volume()

void lg_audio_set_global_volume

(

float

v

)

Set audio (both music AND sounds) volume

Use lg_audio_set_music_volume() or lg_audio_set_sounds_volume() if you need more granular control

Parameters

v	Volume, in range [0.0, 1.0]

lg_audio_set_music_volume()

void lg_audio_set_music_volume

(

float

v

)

Set music volume

Parameters

v	Volume, in range [0.0, 1.0]

lg_audio_set_sounds_volume()

void lg_audio_set_sounds_volume

(

float

v

)

Set sounds volume

Parameters

v	Volume, in range [0.0, 1.0]

lg_audio_pause()

void lg_audio_pause

(

)

Pause all audio playback

lg_audio_resume()

void lg_audio_resume

(

)

Resume all audio playback

lg_audio_stop()

void lg_audio_stop

(

)

Stop all audio playback

lg_audio_get_n_channels()

int lg_audio_get_n_channels

(

)

Get num of available channels

Returns

The num of channels