1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
/*
* standalone sound mixer based on rxi's cmixer.
*/
enum {
FIXED_BITS = 12,
FIXED_UNIT = 1<<FIXED_BITS,
FIXED_MASK = FIXED_UNIT-1,
MIXBUFSIZE = 512,
MIXBUFMASK = MIXBUFSIZE-1,
AUDIO_STATE_STOPPED = 0,
AUDIO_STATE_PLAYING,
AUDIO_STATE_PAUSED,
AUDIO_EVENT_DESTROY = 0,
AUDIO_EVENT_SAMPLES,
AUDIO_EVENT_REWIND
};
typedef struct Pcm Pcm;
typedef struct AudioEvent AudioEvent;
typedef struct AudioSourceInfo AudioSourceInfo;
typedef struct AudioSource AudioSource;
typedef struct Mixer Mixer;
struct Pcm
{
void *data;
int len;
int off;
int depth;
int chans;
int rate;
};
struct AudioEvent
{
int type;
void *udata;
char *msg;
s16int *buffer;
int length;
};
struct AudioSourceInfo
{
void *udata;
int samplerate;
int length;
void (*handler)(AudioEvent *e); /* Event handler */
};
struct AudioSource
{
AudioSource *next; /* Next source in list */
s16int buffer[MIXBUFSIZE]; /* Internal buffer with raw stereo PCM */
void *udata; /* Stream's udata (from AudioSourceInfo) */
int samplerate; /* Stream's native samplerate */
int length; /* Stream's length in samples */
int end; /* End index for the current play-through */
int state; /* Current state (playing|paused|stopped) */
s64int position; /* Current playhead position (fixed point) */
int lgain, rgain; /* Left and right gain (fixed point) */
int rate; /* Playback rate (fixed point) */
int nextfill; /* Next frame idx where the buffer needs to be filled */
int loop; /* Whether the source will loop when `end` is reached */
int rewind; /* Whether the source will rewind before playing */
int active; /* Whether the source is part of `sources` list */
double gain; /* Gain set by `audio_set_gain()` */
double pan; /* Pan set by `audio_set_pan()` */
void (*handler)(AudioEvent *e); /* Event handler */
};
struct Mixer
{
AudioSource *sources; /* Linked list of active (playing) sources */
s32int buffer[MIXBUFSIZE]; /* Internal master buffer */
int samplerate; /* Master samplerate */
int gain; /* Master gain (fixed point) */
};
void initaudio(int);
void audio_set_master_gain(double);
void processaudio(s16int*, int);
AudioSource *newaudiosource(AudioSourceInfo*);
AudioSource *loadaudiosource(char*);
void delaudiosource(AudioSource*);
double audio_get_length(AudioSource*);
double audio_get_position(AudioSource*);
int audio_get_state(AudioSource*);
void audio_set_gain(AudioSource*, double);
void audio_set_pan(AudioSource*, double);
void audio_set_pitch(AudioSource*, double);
void audio_set_loop(AudioSource*, int);
void playaudio(AudioSource*);
void pauseaudio(AudioSource*);
void stopaudio(AudioSource*);
|