/* 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_) */