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/* WMix 3.0 -- a mixer using the OSS mixer API.
* Copyright (C) 2000, 2001
* Daniel Richard G. <skunk@mit.edu>,
* timecop <timecop@japan.co.jp>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* WMVolume mixer interface
*
* Some notes:
*
* - The volume argument is a floating-point value between 0 (no sound) and
* 1 (full sound) inclusively.
*
* - The balance argument is a floating-point value betwen -1 (full left)
* and 1 (full right) inclusively. A value of 0 indicates centered sound.
* If the device does not natively support a balance parameter, use the
* lr_to_vb() and vb_to_lr() functions in misc.c.
*
* - The volume and balance arguments passed to these functions, given that
* they are (usually 32-bit) floating-point values, may be capable of
* specifying the audio parameters at a finer resolution than the
* hardware itself. However, the mixer driver must not quantize the
* volume and balance levels returned by the mixer_get_*() routines.
*
* Example: Suppose the mixer device supports specifying the volume as an
* integer in the range of 0 to 100. If mixer_set_volume() is called with
* an argument of 0.7351, then the device will be set to a volume of 74,
* yet subsequent calls to mixer_get_volume() (assuming mixer state has
* not changed since) will return 0.7351. Only if the mixer state is
* changed by another program (that, say, sets the volume to 51) is the
* value returned by this interface quantized (in such a case returning
* 0.51).
*
* The reason why this quantization must be avoided whenever possible is
* that otherwise, a large number of minuscule increases to the volume
* level will have no cumulative effect. Calling mixer_set_volume_rel()
* ten thousand times with an argument of 0.0001 should successfully
* increase the volume to its maximum, even if the device actually
* supports only 64 discrete volume levels.
*
* - Muting must occur independently of the volume level.
*/
void mixer_init (const char *mixer_device, bool verbose);
bool mixer_is_changed (void);
int mixer_get_channel_count (void);
int mixer_get_channel (void);
const char * mixer_get_channel_name (void);
const char * mixer_get_short_name (void);
void mixer_set_channel (int channel);
void mixer_set_channel_rel (int delta_channel);
float mixer_get_volume (void);
void mixer_set_volume (float volume);
void mixer_set_volume_rel (float delta_volume);
float mixer_get_balance (void);
void mixer_set_balance (float balance);
void mixer_set_balance_rel (float delta_balance);
void mixer_toggle_mute (void);
void mixer_toggle_rec (void);
bool mixer_is_muted (void);
bool mixer_is_stereo (void);
bool mixer_is_rec (void);
bool mixer_can_rec (void);
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