1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/snes_spc/spc.h	Fri Oct 21 05:53:11 2011 -0700
     1.3 @@ -0,0 +1,147 @@
     1.4 +/* SNES SPC-700 APU emulator C interface (also usable from C++) */
     1.5 +
     1.6 +/* snes_spc 0.9.0 */
     1.7 +#ifndef SPC_H
     1.8 +#define SPC_H
     1.9 +
    1.10 +#include <stddef.h>
    1.11 +
    1.12 +#ifdef __cplusplus
    1.13 +	extern "C" {
    1.14 +#endif
    1.15 +
    1.16 +/* Error string return. NULL if success, otherwise error message. */
    1.17 +typedef const char* spc_err_t;
    1.18 +
    1.19 +typedef struct SNES_SPC SNES_SPC;
    1.20 +
    1.21 +/* Creates new SPC emulator. NULL if out of memory. */
    1.22 +SNES_SPC* spc_new( void );
    1.23 +
    1.24 +/* Frees SPC emulator */
    1.25 +void spc_delete( SNES_SPC* );
    1.26 +
    1.27 +/* Sample pairs generated per second */
    1.28 +enum { spc_sample_rate = 32000 };
    1.29 +
    1.30 +
    1.31 +/**** Emulator use ****/
    1.32 +
    1.33 +/* Sets IPL ROM data. Library does not include ROM data. Most SPC music files
    1.34 +don't need ROM, but a full emulator must provide this. */
    1.35 +enum { spc_rom_size = 0x40 };
    1.36 +void spc_init_rom( SNES_SPC*, unsigned char const rom [spc_rom_size] );
    1.37 +
    1.38 +/* Sets destination for output samples */
    1.39 +typedef short spc_sample_t;
    1.40 +void spc_set_output( SNES_SPC*, spc_sample_t* out, int out_size );
    1.41 +
    1.42 +/* Number of samples written to output since last set */
    1.43 +int spc_sample_count( SNES_SPC const* );
    1.44 +
    1.45 +/* Resets SPC to power-on state. This resets your output buffer, so you must
    1.46 +call spc_set_output() after this. */
    1.47 +void spc_reset( SNES_SPC* );
    1.48 +
    1.49 +/* Emulates pressing reset switch on SNES. This resets your output buffer, so
    1.50 +you must call spc_set_output() after this. */
    1.51 +void spc_soft_reset( SNES_SPC* );
    1.52 +
    1.53 +/* 1024000 SPC clocks per second, sample pair every 32 clocks */
    1.54 +typedef int spc_time_t;
    1.55 +enum { spc_clock_rate = 1024000 };
    1.56 +enum { spc_clocks_per_sample = 32 };
    1.57 +
    1.58 +/* Reads/writes port at specified time */
    1.59 +enum { spc_port_count = 4 };
    1.60 +int  spc_read_port ( SNES_SPC*, spc_time_t, int port );
    1.61 +void spc_write_port( SNES_SPC*, spc_time_t, int port, int data );
    1.62 +
    1.63 +/* Runs SPC to end_time and starts a new time frame at 0 */
    1.64 +void spc_end_frame( SNES_SPC*, spc_time_t end_time );
    1.65 +
    1.66 +
    1.67 +/**** Sound control ****/
    1.68 +
    1.69 +/*Mutes voices corresponding to non-zero bits in mask. Reduces emulation accuracy. */
    1.70 +enum { spc_voice_count = 8 };
    1.71 +void spc_mute_voices( SNES_SPC*, int mask );
    1.72 +
    1.73 +/* If true, prevents channels and global volumes from being phase-negated.
    1.74 +Only supported by fast DSP; has no effect on accurate DSP. */
    1.75 +void spc_disable_surround( SNES_SPC*, int disable );
    1.76 +
    1.77 +/* Sets tempo, where spc_tempo_unit = normal, spc_tempo_unit / 2 = half speed, etc. */
    1.78 +enum { spc_tempo_unit = 0x100 };
    1.79 +void spc_set_tempo( SNES_SPC*, int );
    1.80 +
    1.81 +
    1.82 +/**** SPC music playback *****/
    1.83 +
    1.84 +/* Loads SPC data into emulator. Returns NULL on success, otherwise error string. */
    1.85 +spc_err_t spc_load_spc( SNES_SPC*, void const* spc_in, long size );
    1.86 +
    1.87 +/* Clears echo region. Useful after loading an SPC as many have garbage in echo. */
    1.88 +void spc_clear_echo( SNES_SPC* );
    1.89 +
    1.90 +/* Plays for count samples and write samples to out. Discards samples if out
    1.91 +is NULL. Count must be a multiple of 2 since output is stereo. */
    1.92 +spc_err_t spc_play( SNES_SPC*, int count, short* out );
    1.93 +
    1.94 +/* Skips count samples. Several times faster than spc_play(). */
    1.95 +spc_err_t spc_skip( SNES_SPC*, int count );
    1.96 +
    1.97 +
    1.98 +/**** State save/load (only available with accurate DSP) ****/
    1.99 +
   1.100 +/* Saves/loads exact emulator state */
   1.101 +enum { spc_state_size = 67 * 1024L }; /* maximum space needed when saving */
   1.102 +typedef void (*spc_copy_func_t)( unsigned char** io, void* state, size_t );
   1.103 +void spc_copy_state( SNES_SPC*, unsigned char** io, spc_copy_func_t );
   1.104 +
   1.105 +/* Writes minimal SPC file header to spc_out */
   1.106 +void spc_init_header( void* spc_out );
   1.107 +
   1.108 +/* Saves emulator state as SPC file data. Writes spc_file_size bytes to spc_out.
   1.109 +Does not set up SPC header; use spc_init_header() for that. */
   1.110 +enum { spc_file_size = 0x10200 }; /* spc_out must have this many bytes allocated */
   1.111 +void spc_save_spc( SNES_SPC*, void* spc_out );
   1.112 +
   1.113 +/* Returns non-zero if new key-on events occurred since last check. Useful for 
   1.114 +trimming silence while saving an SPC. */
   1.115 +int spc_check_kon( SNES_SPC* );
   1.116 +
   1.117 +
   1.118 +/**** SPC_Filter ****/
   1.119 +
   1.120 +typedef struct SPC_Filter SPC_Filter;
   1.121 +
   1.122 +/* Creates new filter. NULL if out of memory. */
   1.123 +SPC_Filter* spc_filter_new( void );
   1.124 +
   1.125 +/* Frees filter */
   1.126 +void spc_filter_delete( SPC_Filter* );
   1.127 +
   1.128 +/* Filters count samples of stereo sound in place. Count must be a multiple of 2. */
   1.129 +void spc_filter_run( SPC_Filter*, spc_sample_t* io, int count );
   1.130 +
   1.131 +/* Clears filter to silence */
   1.132 +void spc_filter_clear( SPC_Filter* );
   1.133 +
   1.134 +/* Sets gain (volume), where spc_filter_gain_unit is normal. Gains greater than
   1.135 +spc_filter_gain_unit are fine, since output is clamped to 16-bit sample range. */
   1.136 +enum { spc_filter_gain_unit = 0x100 };
   1.137 +void spc_filter_set_gain( SPC_Filter*, int gain );
   1.138 +
   1.139 +/* Sets amount of bass (logarithmic scale) */
   1.140 +enum { spc_filter_bass_none =  0 };
   1.141 +enum { spc_filter_bass_norm =  8 }; /* normal amount */
   1.142 +enum { spc_filter_bass_max  = 31 };
   1.143 +void spc_filter_set_bass( SPC_Filter*, int bass );
   1.144 +
   1.145 +
   1.146 +#ifdef __cplusplus
   1.147 +	}
   1.148 +#endif
   1.149 +
   1.150 +#endif