mirror of
https://github.com/joel16/SDL2.git
synced 2024-12-14 14:59:43 +00:00
1.3 API proposals for audio subsystem. Nothing in here is guaranteed to
stay as-is! And none of it is implemented yet! Use at own risk! --HG-- extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%402011
This commit is contained in:
Ryan C. Gordon
parent
7b00c63ef6
commit
7bc5cd5763
@ -44,11 +44,13 @@ extern "C" {
|
||||
/* *INDENT-ON* */
|
||||
#endif
|
||||
|
||||
typedef Uint16 SDL_AudioFormat;
|
||||
|
||||
/* The calculated values in this structure are calculated by SDL_OpenAudio() */
|
||||
typedef struct SDL_AudioSpec
|
||||
{
|
||||
int freq; /* DSP frequency -- samples per second */
|
||||
Uint16 format; /* Audio data format */
|
||||
SDL_AudioFormat format; /* Audio data format */
|
||||
Uint8 channels; /* Number of channels: 1 mono, 2 stereo */
|
||||
Uint8 silence; /* Audio buffer silence value (calculated) */
|
||||
Uint16 samples; /* Audio buffer size in samples (power of 2) */
|
||||
@ -64,6 +66,36 @@ typedef struct SDL_AudioSpec
|
||||
void *userdata;
|
||||
} SDL_AudioSpec;
|
||||
|
||||
|
||||
/*
|
||||
These are what the 16 bits in SDL_AudioFormat currently mean...
|
||||
(Unspecified bits are always zero.)
|
||||
|
||||
++-----------------------sample is signed if set
|
||||
||
|
||||
|| ++-----------sample is bigendian if set
|
||||
|| ||
|
||||
|| || ++---sample is float if set
|
||||
|| || ||
|
||||
|| || || +---sample bit size---+
|
||||
|| || || | |
|
||||
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
|
||||
|
||||
There are macros in SDL 1.3 and later to query these bits.
|
||||
*/
|
||||
|
||||
#define SDL_AUDIO_MASK_BITSIZE (0xFF)
|
||||
#define SDL_AUDIO_MASK_DATATYPE (1<<8)
|
||||
#define SDL_AUDIO_MASK_ENDIAN (1<<12)
|
||||
#define SDL_AUDIO_MASK_SIGNED (1<<15)
|
||||
#define SDL_AUDIO_BITSIZE(x) (x & SDL_AUDIO_MASK_BITSIZE)
|
||||
#define SDL_AUDIO_ISFLOAT(x) (x & SDL_AUDIO_MASK_DATATYPE)
|
||||
#define SDL_AUDIO_ISBIGENDIAN(x) (x & SDL_AUDIO_MASK_ENDIAN)
|
||||
#define SDL_AUDIO_ISSIGNED(x) (x & SDL_AUDIO_MASK_SIGNED)
|
||||
#define SDL_AUDIO_ISINT(x) (!SDL_AUDIO_ISFLOAT(x))
|
||||
#define SDL_AUDIO_ISLITTLEENDIAN(x) (!SDL_AUDIO_ISBIGENDIAN(x))
|
||||
#define SDL_AUDIO_ISUNSIGNED(x) (!SDL_AUDIO_ISSIGNED(x))
|
||||
|
||||
/* Audio format flags (defaults to LSB byte order) */
|
||||
#define AUDIO_U8 0x0008 /* Unsigned 8-bit samples */
|
||||
#define AUDIO_S8 0x8008 /* Signed 8-bit samples */
|
||||
@ -74,13 +106,32 @@ typedef struct SDL_AudioSpec
|
||||
#define AUDIO_U16 AUDIO_U16LSB
|
||||
#define AUDIO_S16 AUDIO_S16LSB
|
||||
|
||||
/* int32 support new to SDL 1.3 */
|
||||
#define AUDIO_S32LSB 0x8020 /* 32-bit integer samples */
|
||||
#define AUDIO_S32MSB 0x9020 /* As above, but big-endian byte order */
|
||||
#define AUDIO_S32 AUDIO_S32LSB
|
||||
#define AUDIO_U32LSB 0x0020 /* Unsigned 32-bit integer samples */
|
||||
#define AUDIO_U32MSB 0x1020 /* As above, but big-endian byte order */
|
||||
#define AUDIO_U32 AUDIO_U32LSB
|
||||
|
||||
/* float32 support new to SDL 1.3 */
|
||||
#define AUDIO_F32LSB 0x8120 /* 32-bit floating point samples */
|
||||
#define AUDIO_F32MSB 0x9120 /* As above, but big-endian byte order */
|
||||
#define AUDIO_F32 AUDIO_F32LSB
|
||||
|
||||
/* Native audio byte ordering */
|
||||
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
|
||||
#define AUDIO_U16SYS AUDIO_U16LSB
|
||||
#define AUDIO_S16SYS AUDIO_S16LSB
|
||||
#define AUDIO_S32SYS AUDIO_S32LSB
|
||||
#define AUDIO_U32SYS AUDIO_U32LSB
|
||||
#define AUDIO_F32SYS AUDIO_F32LSB
|
||||
#else
|
||||
#define AUDIO_U16SYS AUDIO_U16MSB
|
||||
#define AUDIO_S16SYS AUDIO_S16MSB
|
||||
#define AUDIO_S32SYS AUDIO_S32MSB
|
||||
#define AUDIO_U32SYS AUDIO_U32MSB
|
||||
#define AUDIO_F32SYS AUDIO_F32MSB
|
||||
#endif
|
||||
|
||||
|
||||
@ -165,6 +216,43 @@ extern DECLSPEC const char *SDLCALL SDL_GetCurrentAudioDriver(void);
|
||||
extern DECLSPEC int SDLCALL SDL_OpenAudio(SDL_AudioSpec * desired,
|
||||
SDL_AudioSpec * obtained);
|
||||
|
||||
/*
|
||||
* SDL Audio Device IDs.
|
||||
* A successful call to SDL_OpenAudio() is always device id 1, and legacy
|
||||
* SDL audio APIs assume you want this device ID. SDL_OpenAudioDevice() calls
|
||||
* always returns devices >= 2 on success. The legacy calls are good both
|
||||
* for backwards compatibility and when you don't care about multiple,
|
||||
* specific, or capture devices.
|
||||
*/
|
||||
typedef Uint32 SDL_AudioDeviceID;
|
||||
|
||||
/*
|
||||
* Get the number of available devices exposed by the current driver.
|
||||
* Only valid after a successfully initializing the audio subsystem.
|
||||
*/
|
||||
extern DECLSPEC int SDLCALL SDL_GetNumAudioDevices(int iscapture);
|
||||
|
||||
/*
|
||||
* Get the human-readable name of a specific audio device.
|
||||
* Must be a value between 0 and (number of audio devices-1).
|
||||
* Only valid after a successfully initializing the audio subsystem.
|
||||
*/
|
||||
extern DECLSPEC const char *SDLCALL SDL_GetAudioDevice(int index, int iscapture);
|
||||
|
||||
|
||||
/*
|
||||
* Open a specific audio device. Passing in a device name of NULL is
|
||||
* equivalent to SDL_OpenAudio(). Returns 0 on error, a valid device ID
|
||||
* on success.
|
||||
*/
|
||||
extern DECLSPEC SDL_AudioDeviceID SDLCALL SDL_OpenAudioDevice(
|
||||
const char * device,
|
||||
int iscapture,
|
||||
const SDL_AudioSpec * desired,
|
||||
SDL_AudioSpec * obtained);
|
||||
|
||||
|
||||
|
||||
/*
|
||||
* Get the current audio state:
|
||||
*/
|
||||
@ -176,6 +264,9 @@ typedef enum
|
||||
} SDL_audiostatus;
|
||||
extern DECLSPEC SDL_audiostatus SDLCALL SDL_GetAudioStatus(void);
|
||||
|
||||
extern DECLSPEC SDL_audiostatus SDLCALL SDL_GetAudioDeviceStatus(
|
||||
SDL_AudioDeviceID dev);
|
||||
|
||||
/*
|
||||
* This function pauses and unpauses the audio callback processing.
|
||||
* It should be called with a parameter of 0 after opening the audio
|
||||
@ -184,6 +275,8 @@ extern DECLSPEC SDL_audiostatus SDLCALL SDL_GetAudioStatus(void);
|
||||
* Silence will be written to the audio device during the pause.
|
||||
*/
|
||||
extern DECLSPEC void SDLCALL SDL_PauseAudio(int pause_on);
|
||||
extern DECLSPEC void SDLCALL SDL_PauseAudioDevice(SDL_AudioDeviceID dev,
|
||||
int pause_on);
|
||||
|
||||
/*
|
||||
* This function loads a WAVE from the data source, automatically freeing
|
||||
@ -222,7 +315,8 @@ extern DECLSPEC void SDLCALL SDL_FreeWAV(Uint8 * audio_buf);
|
||||
* and rate, and initializes the 'cvt' structure with information needed
|
||||
* by SDL_ConvertAudio() to convert a buffer of audio data from one format
|
||||
* to the other.
|
||||
* This function returns 0, or -1 if there was an error.
|
||||
* Returns -1 if the format conversion is not supported, 0 if there's
|
||||
* no conversion needed, or 1 if the audio filter is set up.
|
||||
*/
|
||||
extern DECLSPEC int SDLCALL SDL_BuildAudioCVT(SDL_AudioCVT * cvt,
|
||||
Uint16 src_format,
|
||||
@ -253,6 +347,15 @@ extern DECLSPEC int SDLCALL SDL_ConvertAudio(SDL_AudioCVT * cvt);
|
||||
extern DECLSPEC void SDLCALL SDL_MixAudio(Uint8 * dst, const Uint8 * src,
|
||||
Uint32 len, int volume);
|
||||
|
||||
/*
|
||||
* This works like SDL_MixAudio, but you specify the audio format instead of
|
||||
* using the format of audio device 1. Thus it can be used when no audio
|
||||
* device is open at all.
|
||||
*/
|
||||
extern DECLSPEC void SDLCALL SDL_MixAudioFormat(Uint8 * dst, const Uint8 * src,
|
||||
SDL_AudioFormat format,
|
||||
Uint32 len, int volume);
|
||||
|
||||
/*
|
||||
* The lock manipulated by these functions protects the callback function.
|
||||
* During a LockAudio/UnlockAudio pair, you can be guaranteed that the
|
||||
@ -260,12 +363,20 @@ extern DECLSPEC void SDLCALL SDL_MixAudio(Uint8 * dst, const Uint8 * src,
|
||||
* function or you will cause deadlock.
|
||||
*/
|
||||
extern DECLSPEC void SDLCALL SDL_LockAudio(void);
|
||||
extern DECLSPEC void SDLCALL SDL_LockAudioDevice(SDL_AudioDeviceID dev);
|
||||
extern DECLSPEC void SDLCALL SDL_UnlockAudio(void);
|
||||
extern DECLSPEC void SDLCALL SDL_UnlockAudioDevice(SDL_AudioDeviceID dev);
|
||||
|
||||
/*
|
||||
* This function shuts down audio processing and closes the audio device.
|
||||
*/
|
||||
extern DECLSPEC void SDLCALL SDL_CloseAudio(void);
|
||||
extern DECLSPEC void SDLCALL SDL_CloseAudioDevice(SDL_AudioDeviceID dev);
|
||||
|
||||
/*
|
||||
* Returns 1 if audio device is still functioning, zero if not, -1 on error.
|
||||
*/
|
||||
extern DECLSPEC int SDLCALL SDL_AudioDeviceConnected(SDL_AudioDeviceID dev);
|
||||
|
||||
|
||||
/* Ends C function definitions when using C++ */
|
||||
|
||||
Loading…
Reference in New Issue
Block a user