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Diffstat (limited to 'engines/sci/sfx/sfx_pcm.h')
| -rw-r--r-- | engines/sci/sfx/sfx_pcm.h | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/engines/sci/sfx/sfx_pcm.h b/engines/sci/sfx/sfx_pcm.h new file mode 100644 index 0000000000..abb1704741 --- /dev/null +++ b/engines/sci/sfx/sfx_pcm.h @@ -0,0 +1,184 @@ +/* ScummVM - Graphic Adventure Engine + * + * ScummVM is the legal property of its developers, whose names + * are too numerous to list here. Please refer to the COPYRIGHT + * file distributed with this source distribution. + * + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * $URL$ + * $Id$ + * + */ + +#ifndef _SFX_PCM_H_ +#define _SFX_PCM_H_ + +#include "sci/sfx/sfx_core.h" +#include "sci/sfx/sfx_timer.h" +#include "sci/sfx/sfx_time.h" +#include "sci/include/scitypes.h" + +namespace Sci { + +#define SFX_PCM_MONO 0 +#define SFX_PCM_STEREO_LR 1 /* left sample, then right sample */ +#define SFX_PCM_STEREO_RL 2 /* right sample, then left sample */ + +/* The following are used internally by the mixer */ +#define SFX_PCM_FORMAT_LMASK 0x7 +#define SFX_PCM_FORMAT_BE 0 +#define SFX_PCM_FORMAT_LE 1 +#define SFX_PCM_FORMAT_ENDIANNESS 1 +#define SFX_PCM_FORMAT_8 0 +#define SFX_PCM_FORMAT_16 2 + + +/* Pick one of these formats (including the _NATIVE) ones for your PCM feed */ +#define SFX_PCM_FORMAT_U8 (0x0080 | SFX_PCM_FORMAT_8) /* Unsigned (bias 128) 8 bit format */ +#define SFX_PCM_FORMAT_S8 (0x0000 | SFX_PCM_FORMAT_8) /* Signed 8 bit format */ +#define SFX_PCM_FORMAT_U16_LE (0x8000 | SFX_PCM_FORMAT_16 | SFX_PCM_FORMAT_LE) /* Unsigned (bias 32768) 16 bit LE format */ +#define SFX_PCM_FORMAT_S16_LE (0x0000 | SFX_PCM_FORMAT_16 | SFX_PCM_FORMAT_LE) /* Signed 16 bit format, little endian */ +#define SFX_PCM_FORMAT_U16_BE (0x8000 | SFX_PCM_FORMAT_16 | SFX_PCM_FORMAT_BE) /* Unsigned (bias 32768) 16 bit BE format */ +#define SFX_PCM_FORMAT_S16_BE (0x0000 | SFX_PCM_FORMAT_16 | SFX_PCM_FORMAT_BE) /* Signed 16 bit format, big endian */ + +#ifdef SCUMM_BIG_ENDIAN +# define SFX_PCM_FORMAT_U16_NATIVE SFX_PCM_FORMAT_U16_BE +# define SFX_PCM_FORMAT_S16_NATIVE SFX_PCM_FORMAT_S16_BE +#else +# define SFX_PCM_FORMAT_U16_NATIVE SFX_PCM_FORMAT_U16_LE +# define SFX_PCM_FORMAT_S16_NATIVE SFX_PCM_FORMAT_S16_LE +#endif + +#define SFX_PCM_FRAME_SIZE(conf) ((conf).stereo? 2 : 1) * (((conf).format & SFX_PCM_FORMAT_16)? 2 : 1) + + +typedef struct { + int rate; /* Sampling rate */ + int stereo; /* The stereo mode used (SFX_PCM_MONO or SFX_PCM_STEREO_*) */ + unsigned int format; /* Sample format (SFX_PCM_FORMAT_*) */ +} sfx_pcm_config_t; + +typedef struct _sfx_pcm_device { + /* SFX devices are PCM players, i.e. output drivers for digitalised audio (sequences of audio samples). + ** Implementors are (in general) allowed to export specifics of these devices and let the mixer handle + ** endianness/signedness/bit size/mono-vs-stereo conversions. + */ + + int (*init)(struct _sfx_pcm_device *self); + /* Initializes the device + ** Parameters: (sfx_pcm_device_t *) self: Self reference + ** Returns : (int) SFX_OK on success, SFX_ERROR if the device could not be + ** opened + ** This should attempt to open the highest quality output allowed by any options + ** specified beforehand. + */ + + int (*output)(struct _sfx_pcm_device *self, byte *buf, + int count, sfx_timestamp_t *timestamp); + /* Writes output to the device + ** Parameters: (sfx_pcm_device_t *) self: Self reference + ** (byte *) buf: The buffer to write + ** (int) count: Number of /frames/ that should be written + ** (sfx_timestamp_t *) timestamp: Optional point in time + ** for which the PCM data is scheduled + ** Returns : (int) SFX_OK on success, SFX_ERROR on error + ** The size of the buffer allocated as 'buf' equals buf_size. + ** 'buf' is guaranteed not to be modified in between calls to 'output()'. + ** 'timestamp' is guaranteed to be used only in sequential order, but not + ** guaranteed to be used in all cases. It is guaranteed to be compaible with + ** the sample rate used by the device itself (i.e., the sfx_time.h functionality + ** is applicable) + */ + + sfx_timestamp_t + (*get_output_timestamp)(struct _sfx_pcm_device *self); + /* Determines the timestamp for 'output' + ** Parameters: (sfx_pcm_device_t *) self: Self reference + ** Returns : (sfx_timestamp_t) A timestamp (with the device's conf.rate) + ** describing the point in time at which + ** the next frame passed to 'output' + ** will be played + ** This function is OPTIONAL and may be NULL, but it is recommended + ** that pcm device implementers attempt to really implement it. + */ + + /* The following must be set after initialisation */ + sfx_pcm_config_t conf; + int buf_size; /* Output buffer size, i.e. the number of frames (!) + ** that can be queued by this driver before calling + ** output() will block or fail, drained according + ** to conf.rate */ + +} sfx_pcm_device_t; + + +#define PCM_FEED_TIMESTAMP 0 /* New timestamp available */ +#define PCM_FEED_IDLE 1 /* No sound ATM, but new timestamp may be available later */ +#define PCM_FEED_EMPTY 2 /* Feed is finished, can be destroyed */ + +typedef struct _sfx_pcm_feed_t { + /* PCM feeds are sources of input for the PCM mixer. Their member functions + ** are invoked as callbacks on demand, to provide the mixer with input it + ** (in turn) passes on to PCM output devices. + ** PCM feeds must explicitly register themselves with the mixer in order + ** to be considered. + */ + + int (*poll)(struct _sfx_pcm_feed_t *self, byte *dest, int size); + /* Asks the PCM feed to write out the next stuff it would like to have written + ** Parameters: (sfx_pcm_feed_t *) self: Self reference + ** (byte *) dest: The destination buffer to write to + ** (int) size: The maximum number of _frames_ (not neccessarily bytes) + ** to write + ** Returns : (int) The number of frames written + ** If the number of frames written is smaller than 'size', the PCM feed will + ** be queried for a new timestamp afterwards, or destroyed if no new timestamp + ** is available. + */ + + void (*destroy)(struct _sfx_pcm_feed_t *self); + /* Asks the PCM feed to free all resources it occupies + ** Parameters: (sfx_pcm_feed_t *) self: Self reference + ** free(self) should be part of this function, if applicable. + */ + + int + (*get_timestamp)(struct _sfx_pcm_feed_t *self, sfx_timestamp_t *timestamp); + /* Determines the timestamp of the next frame-to-read + ** Returns : (sfx_timestamp_t) timestamp: The timestamp of the next frame + ** (int) PCM_FEED_* + ** This function is OPTIONAL and may be NULL + */ + + void *internal; /* The private bits of a PCM feed. */ + + sfx_pcm_config_t conf; /* The channel's setup */ + + const char *debug_name; /* The channel name, for debugging */ + int debug_nr; /* A channel number relative to the channel name, for debugging + ** (print in hex) */ + int frame_size; /* Frame size, computed by the mixer for the feed */ + +} sfx_pcm_feed_t; + +int sfx_pcm_available(); +/* Determines whether a PCM device is available and has been initialised +** Returns : (int) zero iff no PCM device is available +*/ + +} // End of namespace Sci + +#endif /* !defined(_SFX_PCM_H_) */ |