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mirror of https://github.com/dpethes/rerogue.git synced 2025-06-07 18:58:32 +02:00
rerogue/model_viewer/sdl2/sdlaudio.inc
2017-02-02 02:08:13 +01:00

569 lines
26 KiB
PHP

//from sdl_audio.h
{**
* Audio format flags.
*
* 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 2.0 and later to query these bits.
*}
type
TSDL_AudioFormat = UInt16;
{**
* Audio flags
*}
const
SDL_AUDIO_MASK_BITSIZE = ($FF);
SDL_AUDIO_MASK_DATATYPE = (1 shl 8);
SDL_AUDIO_MASK_ENDIAN = (1 shl 12);
SDL_AUDIO_MASK_SIGNED = (1 shl 15);
function SDL_AUDIO_BITSIZE(x: Cardinal): Cardinal;
function SDL_AUDIO_ISFLOAT(x: Cardinal): Cardinal;
function SDL_AUDIO_ISBIGENDIAN(x: Cardinal): Cardinal;
function SDL_AUDIO_ISSIGNED(x: Cardinal): Cardinal;
function SDL_AUDIO_ISINT(x: Cardinal): Cardinal;
function SDL_AUDIO_ISLITTLEENDIAN(x: Cardinal): Cardinal;
function SDL_AUDIO_ISUNSIGNED(x: Cardinal): Cardinal;
{**
* Audio format flags
*
* Defaults to LSB byte order.
*}
const
AUDIO_U8 = $0008; {**< Unsigned 8-bit samples *}
AUDIO_S8 = $8008; {**< Signed 8-bit samples *}
AUDIO_U16LSB = $0010; {**< Unsigned 16-bit samples *}
AUDIO_S16LSB = $8010; {**< Signed 16-bit samples *}
AUDIO_U16MSB = $1010; {**< As above, but big-endian byte order *}
AUDIO_S16MSB = $9010; {**< As above, but big-endian byte order *}
AUDIO_U16 = AUDIO_U16LSB;
AUDIO_S16 = AUDIO_S16LSB;
{**
* int32 support
*}
const
AUDIO_S32LSB = $8020; {**< 32-bit integer samples *}
AUDIO_S32MSB = $9020; {**< As above, but big-endian byte order *}
AUDIO_S32 = AUDIO_S32LSB;
{**
* float32 support
*}
const
AUDIO_F32LSB = $8120; {**< 32-bit floating point samples *}
AUDIO_F32MSB = $9120; {**< As above, but big-endian byte order *}
AUDIO_F32 = AUDIO_F32LSB;
{**
* Native audio byte ordering
*}
{$IFDEF FPC}
{$IF DEFINED(ENDIAN_LITTLE)}
AUDIO_U16SYS = AUDIO_U16LSB;
AUDIO_S16SYS = AUDIO_S16LSB;
AUDIO_S32SYS = AUDIO_S32LSB;
AUDIO_F32SYS = AUDIO_F32LSB;
{$ELSEIF DEFINED(ENDIAN_BIG)}
AUDIO_U16SYS = AUDIO_U16MSB;
AUDIO_S16SYS = AUDIO_S16MSB;
AUDIO_S32SYS = AUDIO_S32MSB;
AUDIO_F32SYS = AUDIO_F32MSB;
{$ELSE}
{$FATAL Cannot determine endianness.}
{$IFEND}
{$ENDIF}
{**
* Allow change flags
*
* Which audio format changes are allowed when opening a device.
*}
const
SDL_AUDIO_ALLOW_FREQUENCY_CHANGE = $00000001;
SDL_AUDIO_ALLOW_FORMAT_CHANGE = $00000002;
SDL_AUDIO_ALLOW_CHANNELS_CHANGE = $00000004;
SDL_AUDIO_ALLOW_ANY_CHANGE = (SDL_AUDIO_ALLOW_FREQUENCY_CHANGE or
SDL_AUDIO_ALLOW_FORMAT_CHANGE or
SDL_AUDIO_ALLOW_CHANNELS_CHANGE);
{*Audio flags*}
{**
* This function is called when the audio device needs more data.
*
* userdata An application-specific parameter saved in
* the SDL_AudioSpec structure
* stream A pointer to the audio data buffer.
* len The length of that buffer in bytes.
*
* Once the callback returns, the buffer will no longer be valid.
* Stereo samples are stored in a LRLRLR ordering.
*}
type
TSDL_AudioCallback = procedure(userdata: Pointer; stream: PUInt8; len: Integer) cdecl;
{**
* The calculated values in this structure are calculated by SDL_OpenAudio().
*}
type
PSDL_AudioSpec = ^TSDL_AudioSpec;
TSDL_AudioSpec = record
freq: Integer; {**< DSP frequency -- samples per second *}
format: TSDL_AudioFormat; {**< Audio data format *}
channels: UInt8; {**< Number of channels: 1 mono, 2 stereo *}
silence: UInt8; {**< Audio buffer silence value (calculated) *}
samples: UInt16; {**< Audio buffer size in samples (power of 2) *}
padding: UInt16; {**< Necessary for some compile environments *}
size: UInt32; {**< Audio buffer size in bytes (calculated) *}
callback: TSDL_AudioCallback;
userdata: Pointer;
end;
PSDL_AudioCVT = ^TSDL_AudioCVT;
TSDL_AudioFilter = procedure(cvt: PSDL_AudioCVT; format: TSDL_AudioFormat) cdecl;
{**
* A structure to hold a set of audio conversion filters and buffers.
*}
TSDL_AudioCVT = record
needed: Integer; {**< Set to 1 if conversion possible *}
src_format: TSDL_AudioFormat; {**< Source audio format *}
dst_format: TSDL_AudioFormat; {**< Target audio format *}
rate_incr: Double; {**< Rate conversion increment *}
buf: PUInt8; {**< Buffer to hold entire audio data *}
len: Integer; {**< Length of original audio buffer *}
len_cvt: Integer; {**< Length of converted audio buffer *}
len_mult: Integer; {**< buffer must be len*len_mult big *}
len_ratio: Double; {**< Given len, final size is len*len_ratio *}
filters: array[0..9] of TSDL_AudioFilter; {**< Filter list *}
filter_index: Integer; {**< Current audio conversion function *}
end;
{* Function prototypes *}
{**
* Driver discovery functions
*
* These functions return the list of built in audio drivers, in the
* order that they are normally initialized by default.
*}
function SDL_GetNumAudioDrivers: Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetNumAudioDrivers' {$ENDIF} {$ENDIF};
function SDL_GetAudioDriver(index: Integer): PAnsiChar cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioDriver' {$ENDIF} {$ENDIF};
{**
* Initialization and cleanup
*
* These functions are used internally, and should not be used unless
* you have a specific need to specify the audio driver you want to
* use. You should normally use SDL_Init() or SDL_InitSubSystem().
*}
function SDL_AudioInit(driver_name: PAnsiChar): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_AudioInit' {$ENDIF} {$ENDIF};
procedure SDL_AudioQuit cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_AudioQuit' {$ENDIF} {$ENDIF};
{**
* This function returns the name of the current audio driver, or NULL
* if no driver has been initialized.
*}
function SDL_GetCurrentAudioDriver: PAnsiChar cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetCurrentAudioDriver' {$ENDIF} {$ENDIF};
{**
* This function opens the audio device with the desired parameters, and
* returns 0 if successful, placing the actual hardware parameters in the
* structure pointed to by obtained. If obtained is NULL, the audio
* data passed to the callback function will be guaranteed to be in the
* requested format, and will be automatically converted to the hardware
* audio format if necessary. This function returns -1 if it failed
* to open the audio device, or couldn't set up the audio thread.
*
* When filling in the desired audio spec structure,
* - desired->freq should be the desired audio frequency in samples-per-
* second.
* - desired->format should be the desired audio format.
* - desired->samples is the desired size of the audio buffer, in
* samples. This number should be a power of two, and may be adjusted by
* the audio driver to a value more suitable for the hardware. Good values
* seem to range between 512 and 8096 inclusive, depending on the
* application and CPU speed. Smaller values yield faster response time,
* but can lead to underflow if the application is doing heavy processing
* and cannot fill the audio buffer in time. A stereo sample consists of
* both right and left channels in LR ordering.
* Note that the number of samples is directly related to time by the
* following formula: ms := (samples*1000)/freq;
* - desired->size is the size in bytes of the audio buffer, and is
* calculated by SDL_OpenAudio().
* - desired->silence is the value used to set the buffer to silence,
* and is calculated by SDL_OpenAudio().
* - desired->callback should be set to a function that will be called
* when the audio device is ready for more data. It is passed a pointer
* to the audio buffer, and the length in bytes of the audio buffer.
* This function usually runs in a separate thread, and so you should
* protect data structures that it accesses by calling SDL_LockAudio()
* and SDL_UnlockAudio() in your code.
* - desired->userdata is passed as the first parameter to your callback
* function.
*
* The audio device starts out playing silence when it's opened, and should
* be enabled for playing by calling SDL_PauseAudio(0) when you are ready
* for your audio callback function to be called. Since the audio driver
* may modify the requested size of the audio buffer, you should allocate
* any local mixing buffers after you open the audio device.
*}
function SDL_OpenAudio(desired: PSDL_AudioSpec; obtained: PSDL_AudioSpec): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_OpenAudio' {$ENDIF} {$ENDIF};
{**
* SDL Audio Device IDs.
*
* A successful call to SDL_OpenAudio() is always device id 1, and legacy
* SDL audio APIs assume you want this device ID. SDL_OpenAudioDevice() calls
* always returns devices >= 2 on success. The legacy calls are good both
* for backwards compatibility and when you don't care about multiple,
* specific, or capture devices.
*}
type
TSDL_AudioDeviceID = UInt32;
{**
* Get the number of available devices exposed by the current driver.
* Only valid after a successfully initializing the audio subsystem.
* Returns -1 if an explicit list of devices can't be determined; this is
* not an error. For example, if SDL is set up to talk to a remote audio
* server, it can't list every one available on the Internet, but it will
* still allow a specific host to be specified to SDL_OpenAudioDevice().
*
* In many common cases, when this function returns a value <= 0, it can still
* successfully open the default device (NULL for first argument of
* SDL_OpenAudioDevice()).
*}
function SDL_GetNumAudioDevices(iscapture: Integer): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetNumAudioDevices' {$ENDIF} {$ENDIF};
{**
* Get the human-readable name of a specific audio device.
* Must be a value between 0 and (number of audio devices-1).
* Only valid after a successfully initializing the audio subsystem.
* The values returned by this function reflect the latest call to
* SDL_GetNumAudioDevices(); recall that function to redetect available
* hardware.
*
* The string returned by this function is UTF-8 encoded, read-only, and
* managed internally. You are not to free it. If you need to keep the
* string for any length of time, you should make your own copy of it, as it
* will be invalid next time any of several other SDL functions is called.
*}
function SDL_GetAudioDeviceName(index: Integer; iscapture: Integer): PAnsiChar cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioDeviceName' {$ENDIF} {$ENDIF};
{**
* Open a specific audio device. Passing in a device name of NULL requests
* the most reasonable default (and is equivalent to calling SDL_OpenAudio()).
*
* The device name is a UTF-8 string reported by SDL_GetAudioDeviceName(), but
* some drivers allow arbitrary and driver-specific strings, such as a
* hostname/IP address for a remote audio server, or a filename in the
* diskaudio driver.
*
* 0 on error, a valid device ID that is >= 2 on success.
*
* SDL_OpenAudio(), unlike this function, always acts on device ID 1.
*}
function SDL_OpenAudioDevice(device: PAnsiChar;
iscapture: Integer;
desired: PSDL_AudioSpec;
obtained: PSDL_AudioSpec;
allowed_changes: Integer): TSDL_AudioDeviceID cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_OpenAudioDevice' {$ENDIF} {$ENDIF};
{**
* Audio state
*
* Get the current audio state.
*}
type
TSDL_AudioStatus = (SDL_AUDIO_STOPPED,SDL_AUDIO_PLAYING,SDL_AUDIO_PAUSED);
function SDL_GetAudioStatus: TSDL_AudioStatus cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioStatus' {$ENDIF} {$ENDIF};
function SDL_GetAudioDeviceStatus(dev: TSDL_AudioDeviceID): TSDL_AudioStatus cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetAudioDeviceStatus' {$ENDIF} {$ENDIF};
{*Audio State*}
{**
* Pause audio functions
*
* These functions pause and unpause the audio callback processing.
* They should be called with a parameter of 0 after opening the audio
* device to start playing sound. This is so you can safely initialize
* data for your callback function after opening the audio device.
* Silence will be written to the audio device during the pause.
*}
procedure SDL_PauseAudio(pause_on: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_PauseAudio' {$ENDIF} {$ENDIF};
procedure SDL_PauseAudioDevice(dev: TSDL_AudioDeviceID; pause_on: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_PauseAudioDevice' {$ENDIF} {$ENDIF};
{*Pause audio functions*}
{**
* This function loads a WAVE from the data source, automatically freeing
* that source if freesrc is non-zero. For example, to load a WAVE file,
* you could do:
*
* SDL_LoadWAV_RW(SDL_RWFromFile("sample.wav", "rb"), 1, ...);
*
*
* If this function succeeds, it returns the given SDL_AudioSpec,
* filled with the audio data format of the wave data, and sets
* *audio_buf to a malloc()'d buffer containing the audio data,
* and sets *audio_len to the length of that audio buffer, in bytes.
* You need to free the audio buffer with SDL_FreeWAV() when you are
* done with it.
*
* This function returns NULL and sets the SDL error message if the
* wave file cannot be opened, uses an unknown data format, or is
* corrupt. Currently raw and MS-ADPCM WAVE files are supported.
*}
function SDL_LoadWAV_RW(src: PSDL_RWops; freesrc: Integer; spec: PSDL_AudioSpec; audio_buf: PPUInt8; audio_len: PUInt32): PSDL_AudioSpec cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_LoadWAV_RW' {$ENDIF} {$ENDIF};
{**
* Loads a WAV from a file.
* Compatibility convenience function.
*}
function SDL_LoadWAV(_file: PAnsiChar; spec: PSDL_AudioSpec; audio_buf: PPUInt8; audio_len: PUInt32): PSDL_AudioSpec;
{**
* This function frees data previously allocated with SDL_LoadWAV_RW()
*}
procedure SDL_FreeWAV(audio_buf: PUInt8) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_FreeWAV' {$ENDIF} {$ENDIF};
{**
* This function takes a source format and rate and a destination format
* and rate, and initializes the cvt structure with information needed
* by SDL_ConvertAudio() to convert a buffer of audio data from one format
* to the other.
*
* -1 if the format conversion is not supported, 0 if there's
* no conversion needed, or 1 if the audio filter is set up.
*}
function SDL_BuildAudioCVT(cvt: PSDL_AudioCVT;
src_format: TSDL_AudioFormat;
src_channels: UInt8;
src_rate: Integer;
dst_format: TSDL_AudioFormat;
dst_channels: UInt8;
dst_rate: Integer): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_BuildAudioCVT' {$ENDIF} {$ENDIF};
{**
* Once you have initialized the cvt structure using SDL_BuildAudioCVT(),
* created an audio buffer cvt->buf, and filled it with cvt->len bytes of
* audio data in the source format, this function will convert it in-place
* to the desired format.
*
* The data conversion may expand the size of the audio data, so the buffer
* cvt->buf should be allocated after the cvt structure is initialized by
* SDL_BuildAudioCVT(), and should be cvt->len*cvt->len_mult bytes long.
*}
function SDL_ConvertAudio(cvt: PSDL_AudioCVT): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_ConvertAudio' {$ENDIF} {$ENDIF};
const
SDL_MIX_MAXVOLUME = 128;
{**
* This takes two audio buffers of the playing audio format and mixes
* them, performing addition, volume adjustment, and overflow clipping.
* The volume ranges from 0 - 128, and should be set to ::SDL_MIX_MAXVOLUME
* for full audio volume. Note this does not change hardware volume.
* This is provided for convenience -- you can mix your own audio data.
*}
procedure SDL_MixAudio(dst: PUInt8; src: PUInt8; len: UInt32; volume: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_MixAudio' {$ENDIF} {$ENDIF};
{**
* This works like SDL_MixAudio(), but you specify the audio format instead of
* using the format of audio device 1. Thus it can be used when no audio
* device is open at all.
*}
procedure SDL_MixAudioFormat(dst: PUInt8; src: PUInt8; format: TSDL_AudioFormat; len: UInt32; volume: Integer) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_MixAudioFormat' {$ENDIF} {$ENDIF};
{**
* Queue more audio on non-callback devices.
*
* SDL offers two ways to feed audio to the device: you can either supply a
* callback that SDL triggers with some frequency to obtain more audio
* (pull method), or you can supply no callback, and then SDL will expect
* you to supply data at regular intervals (push method) with this function.
*
* There are no limits on the amount of data you can queue, short of
* exhaustion of address space. Queued data will drain to the device as
* necessary without further intervention from you. If the device needs
* audio but there is not enough queued, it will play silence to make up
* the difference. This means you will have skips in your audio playback
* if you aren't routinely queueing sufficient data.
*
* This function copies the supplied data, so you are safe to free it when
* the function returns. This function is thread-safe, but queueing to the
* same device from two threads at once does not promise which buffer will
* be queued first.
*
* You may not queue audio on a device that is using an application-supplied
* callback; doing so returns an error. You have to use the audio callback
* or queue audio with this function, but not both.
*
* You should not call SDL_LockAudio() on the device before queueing; SDL
* handles locking internally for this function.
*
* \param dev The device ID to which we will queue audio.
* \param data The data to queue to the device for later playback.
* \param len The number of bytes (not samples!) to which (data) points.
* \return zero on success, -1 on error.
*
* \sa SDL_GetQueuedAudioSize
* \sa SDL_ClearQueuedAudio
*}
function SDL_QueueAudio(dev: TSDL_AudioDeviceID; data: Pointer; len: UInt32): SInt32; cdecl;
external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_QueueAudio' {$ENDIF} {$ENDIF};
{**
* Dequeue more audio on non-callback devices.
*
* (If you are looking to queue audio for output on a non-callback playback
* device, you want SDL_QueueAudio() instead. This will always return 0
* if you use it with playback devices.)
*
* SDL offers two ways to retrieve audio from a capture device: you can
* either supply a callback that SDL triggers with some frequency as the
* device records more audio data, (push method), or you can supply no
* callback, and then SDL will expect you to retrieve data at regular
* intervals (pull method) with this function.
*
* There are no limits on the amount of data you can queue, short of
* exhaustion of address space. Data from the device will keep queuing as
* necessary without further intervention from you. This means you will
* eventually run out of memory if you aren't routinely dequeueing data.
*
* Capture devices will not queue data when paused; if you are expecting
* to not need captured audio for some length of time, use
* SDL_PauseAudioDevice() to stop the capture device from queueing more
* data. This can be useful during, say, level loading times. When
* unpaused, capture devices will start queueing data from that point,
* having flushed any capturable data available while paused.
*
* This function is thread-safe, but dequeueing from the same device from
* two threads at once does not promise which thread will dequeued data
* first.
*
* You may not dequeue audio from a device that is using an
* application-supplied callback; doing so returns an error. You have to use
* the audio callback, or dequeue audio with this function, but not both.
*
* You should not call SDL_LockAudio() on the device before queueing; SDL
* handles locking internally for this function.
*
* \param dev The device ID from which we will dequeue audio.
* \param data A pointer into where audio data should be copied.
* \param len The number of bytes (not samples!) to which (data) points.
* \return number of bytes dequeued, which could be less than requested.
*
* \sa SDL_GetQueuedAudioSize
* \sa SDL_ClearQueuedAudio
*}
function SDL_DequeueAudio(dev: TSDL_AudioDeviceID; data: Pointer; len:Uint32):Uint32; cdecl;
external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_DequeueAudio' {$ENDIF} {$ENDIF};
{**
* Get the number of bytes of still-queued audio.
*
* This is the number of bytes that have been queued for playback with
* SDL_QueueAudio(), but have not yet been sent to the hardware.
*
* Once we've sent it to the hardware, this function can not decide the exact
* byte boundary of what has been played. It's possible that we just gave the
* hardware several kilobytes right before you called this function, but it
* hasn't played any of it yet, or maybe half of it, etc.
*
* You may not queue audio on a device that is using an application-supplied
* callback; calling this function on such a device always returns 0.
* You have to use the audio callback or queue audio with SDL_QueueAudio(),
* but not both.
*
* You should not call SDL_LockAudio() on the device before querying; SDL
* handles locking internally for this function.
*
* \param dev The device ID of which we will query queued audio size.
* \return Number of bytes (not samples!) of queued audio.
*
* \sa SDL_QueueAudio
* \sa SDL_ClearQueuedAudio
*}
function SDL_GetQueuedAudioSize(dev: TSDL_AudioDeviceID): UInt32; cdecl;
external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_GetQueuedAudioSize' {$ENDIF} {$ENDIF};
{**
* Drop any queued audio data waiting to be sent to the hardware.
*
* Immediately after this call, SDL_GetQueuedAudioSize() will return 0 and
* the hardware will start playing silence if more audio isn't queued.
*
* This will not prevent playback of queued audio that's already been sent
* to the hardware, as we can not undo that, so expect there to be some
* fraction of a second of audio that might still be heard. This can be
* useful if you want to, say, drop any pending music during a level change
* in your game.
*
* You may not queue audio on a device that is using an application-supplied
* callback; calling this function on such a device is always a no-op.
* You have to use the audio callback or queue audio with SDL_QueueAudio(),
* but not both.
*
* You should not call SDL_LockAudio() on the device before clearing the
* queue; SDL handles locking internally for this function.
*
* This function always succeeds and thus returns void.
*
* \param dev The device ID of which to clear the audio queue.
*
* \sa SDL_QueueAudio
* \sa SDL_GetQueuedAudioSize
*}
procedure SDL_ClearQueuedAudio(dev: TSDL_AudioDeviceID); cdecl;
external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_ClearQueuedAudio' {$ENDIF} {$ENDIF};
{**
* Audio lock functions
*
* The lock manipulated by these functions protects the callback function.
* During a SDL_LockAudio()/SDL_UnlockAudio() pair, you can be guaranteed that
* the callback function is not running. Do not call these from the callback
* function or you will cause deadlock.
*}
procedure SDL_LockAudio cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_LockAudio' {$ENDIF} {$ENDIF};
procedure SDL_LockAudioDevice(dev: TSDL_AudioDeviceID) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_LockAudioDevice' {$ENDIF} {$ENDIF};
procedure SDL_UnlockAudio cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_Unlock' {$ENDIF} {$ENDIF};
procedure SDL_UnlockAudioDevice(dev: TSDL_AudioDeviceID) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_UnlockAudioDevice' {$ENDIF} {$ENDIF};
{*Audio lock functions*}
{**
* This function shuts down audio processing and closes the audio device.
*}
procedure SDL_CloseAudio cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_CloseAudio' {$ENDIF} {$ENDIF};
procedure SDL_CloseAudioDevice(dev: TSDL_AudioDeviceID) cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_CloseAudioDevice' {$ENDIF} {$ENDIF};
{**
* 1 if audio device is still functioning, zero if not, -1 on error.
*}
function SDL_AudioDeviceConnected(dev: TSDL_AudioDeviceID): Integer cdecl; external SDL_LibName {$IFDEF DELPHI} {$IFDEF MACOS} name '_SDL_AudioDeviceConnected' {$ENDIF} {$ENDIF};