Search
lxdream.org :: lxdream/src/aica/audio.h
lxdream 0.9.1
released Jun 29
Download Now
filename src/aica/audio.h
changeset 111:230243c2b520
prev106:9048bac046c3
next434:8af49a412d92
author nkeynes
date Thu Mar 16 12:41:59 2006 +0000 (15 years ago)
permissions -rw-r--r--
last change Handle driver-unable-to-init case
file annotate diff log raw
nkeynes@66
     1
/**
nkeynes@111
     2
 * $Id: audio.h,v 1.7 2006-03-16 12:41:59 nkeynes Exp $
nkeynes@66
     3
 * 
nkeynes@66
     4
 * Audio engine, ie the part that does the actual work.
nkeynes@66
     5
 *
nkeynes@66
     6
 * Copyright (c) 2005 Nathan Keynes.
nkeynes@66
     7
 *
nkeynes@66
     8
 * This program is free software; you can redistribute it and/or modify
nkeynes@66
     9
 * it under the terms of the GNU General Public License as published by
nkeynes@66
    10
 * the Free Software Foundation; either version 2 of the License, or
nkeynes@66
    11
 * (at your option) any later version.
nkeynes@66
    12
 *
nkeynes@66
    13
 * This program is distributed in the hope that it will be useful,
nkeynes@66
    14
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@66
    15
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@66
    16
 * GNU General Public License for more details.
nkeynes@66
    17
 */
nkeynes@66
    18
#ifndef dream_audio_H
nkeynes@66
    19
#define dream_audio_H 1
nkeynes@66
    20
nkeynes@66
    21
#include <stdint.h>
nkeynes@66
    22
#include <glib/gtypes.h>
nkeynes@66
    23
nkeynes@66
    24
#ifdef __cplusplus
nkeynes@66
    25
extern "C" {
nkeynes@66
    26
#endif
nkeynes@66
    27
nkeynes@66
    28
#define AUDIO_FMT_8BIT 0
nkeynes@66
    29
#define AUDIO_FMT_16BIT 1
nkeynes@66
    30
#define AUDIO_FMT_ADPCM 2
nkeynes@66
    31
#define AUDIO_FMT_MONO 0
nkeynes@66
    32
#define AUDIO_FMT_STEREO 4
nkeynes@66
    33
#define AUDIO_FMT_SIGNED 0
nkeynes@66
    34
#define AUDIO_FMT_UNSIGNED 8
nkeynes@66
    35
nkeynes@106
    36
#define AUDIO_FMT_16ST (AUDIO_FMT_16BIT|AUDIO_FMT_STEREO)
nkeynes@66
    37
nkeynes@66
    38
typedef struct audio_channel {
nkeynes@66
    39
    gboolean active;
nkeynes@66
    40
    uint32_t posn;
nkeynes@66
    41
    uint32_t posn_left;
nkeynes@66
    42
    uint32_t start;
nkeynes@66
    43
    uint32_t end;
nkeynes@73
    44
    gboolean loop;
nkeynes@66
    45
    uint32_t loop_start;
nkeynes@82
    46
    int vol; /* 0..255 */
nkeynes@82
    47
    int pan; /* 0 (left) .. 31 (right) */
nkeynes@66
    48
    uint32_t sample_rate;
nkeynes@66
    49
    int sample_format; 
nkeynes@66
    50
    /* Envelope etc stuff */
nkeynes@66
    51
    /* ADPCM */
nkeynes@66
    52
    int adpcm_nibble; /* 0 = low nibble, 1 = high nibble */
nkeynes@66
    53
    int adpcm_step;
nkeynes@66
    54
    int adpcm_predict;
nkeynes@66
    55
} *audio_channel_t;
nkeynes@66
    56
nkeynes@66
    57
nkeynes@66
    58
typedef struct audio_buffer {
nkeynes@73
    59
    uint32_t length; /* Bytes */
nkeynes@73
    60
    uint32_t posn; /* Bytes */
nkeynes@66
    61
    int status;
nkeynes@66
    62
    char data[0];
nkeynes@66
    63
} *audio_buffer_t;
nkeynes@66
    64
nkeynes@91
    65
typedef struct audio_driver {
nkeynes@74
    66
    char *name;
nkeynes@66
    67
    gboolean (*set_output_format)( uint32_t sample_rate, uint32_t format );
nkeynes@66
    68
    gboolean (*process_buffer)( audio_buffer_t buffer );
nkeynes@91
    69
} *audio_driver_t;
nkeynes@66
    70
nkeynes@106
    71
extern struct audio_driver audio_null_driver;
nkeynes@106
    72
extern struct audio_driver audio_esd_driver;
nkeynes@66
    73
nkeynes@66
    74
/**
nkeynes@66
    75
 * Set the output driver, sample rate and format. Also initializes the 
nkeynes@66
    76
 * output buffers, flushing any current data and reallocating as 
nkeynes@66
    77
 * necessary. Must be called before attempting to generate any audio.
nkeynes@66
    78
 */
nkeynes@111
    79
gboolean audio_set_driver( audio_driver_t driver, uint32_t samplerate,
nkeynes@66
    80
		       int format );
nkeynes@66
    81
nkeynes@66
    82
/**
nkeynes@66
    83
 * Mark the current write buffer as full and prepare the next buffer for
nkeynes@66
    84
 * writing. Returns the next buffer to write to.
nkeynes@66
    85
 * If all buffers are full, returns NULL.
nkeynes@66
    86
 */
nkeynes@66
    87
audio_buffer_t audio_next_write_buffer();
nkeynes@66
    88
nkeynes@66
    89
/**
nkeynes@66
    90
 * Mark the current read buffer as empty and return the next buffer for
nkeynes@66
    91
 * reading. If there is no next buffer yet, returns NULL.
nkeynes@66
    92
 */
nkeynes@66
    93
audio_buffer_t audio_next_read_buffer();
nkeynes@66
    94
nkeynes@66
    95
/**
nkeynes@66
    96
 * Mix a single output sample and append it to the output buffers
nkeynes@66
    97
 */
nkeynes@73
    98
void audio_mix_samples( int num_samples );
nkeynes@66
    99
nkeynes@66
   100
/**
nkeynes@66
   101
 * Retrieve the channel information for the channel, numbered 0..63. 
nkeynes@66
   102
 */
nkeynes@66
   103
audio_channel_t audio_get_channel( int channel );
nkeynes@66
   104
nkeynes@66
   105
void audio_start_channel( int channel );
nkeynes@66
   106
void audio_stop_channel( int channel );
nkeynes@66
   107
nkeynes@66
   108
nkeynes@66
   109
#ifdef __cplusplus
nkeynes@66
   110
}
nkeynes@66
   111
#endif
nkeynes@66
   112
#endif
.