[LAD] `ags` and libinstpatch

[Joël Krähemann]

Hi, recently I found libinstpatch in debian repository. How can I read a
Instrument with this library? Please take a look at
sourceforge.net/projects/ags. 

libinstpatch will be initialized in main function.

The following functions are involved:

gboolean
ags_ipatch_open(AgsPlayable *playable, gchar *filename);

gboolean
ags_ipatch_sf2_reader_open(AgsPlayable *playable, gchar *filename);

void
ags_ipatch_sf2_reader_level_select(AgsPlayable *playable,
                                   guint nth_level, gchar
*sublevel_name,
                                   GError **error);

void
ags_ipatch_sf2_reader_iter_start(AgsPlayable *playable);

gboolean
ags_ipatch_sf2_reader_iter_next(AgsPlayable *playable);

void
ags_ipatch_sf2_reader_info(AgsPlayable *playable,
                           guint *channels, guint *frames,
                           guint *loop_start, guint *loop_end,
                           GError **error);

short*
ags_ipatch_sf2_reader_read(AgsPlayable *playable,
                           guint channel,
                           GError **error);


then it will be translated to ags format AgsAudioSignal by:

GList*
ags_playable_read_audio_signal(AgsPlayable *playable,
                               AgsDevout *devout,
                               guint start_channel, guint
channels_to_read);