gzdoom-gles/snes_spc/snes_spc/dsp.h
Randy Heit 3bfcc5c09c - Removed lots of spc_* cvars that are no longer meaningful and changed
spc_amp from a x.4 fixed point number to a normal float.
- Switched SPC playback from the external SNESAPU.DLL to Blargg's LGPL
  snes_spc library. I've compiled it with the fast DSP rather than the
  highly accurate one, since I didn't notice a meaningful difference between
  the two in my limited testing. In short: SPC playback is now built in to
  ZDoom. You don't need to download anything extra to make it work, and it
  also works on Linux as well as Windows (though building with Linux is
  currently untested).
- Fixed: Stereo separation was calculated very wrongly when in 2D sound mode.


SVN r794 (trunk)
2008-03-11 22:17:57 +00:00

83 lines
2.5 KiB
C

/* SNES SPC-700 DSP emulator C interface (also usable from C++) */
/* snes_spc 0.9.0 */
#ifndef DSP_H
#define DSP_H
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
typedef struct SPC_DSP SPC_DSP;
/* Creates new DSP emulator. NULL if out of memory. */
SPC_DSP* spc_dsp_new( void );
/* Frees DSP emulator */
void spc_dsp_delete( SPC_DSP* );
/* Initializes DSP and has it use the 64K RAM provided */
void spc_dsp_init( SPC_DSP*, void* ram_64k );
/* Sets destination for output samples. If out is NULL or out_size is 0,
doesn't generate any. */
typedef short spc_dsp_sample_t;
void spc_dsp_set_output( SPC_DSP*, spc_dsp_sample_t* out, int out_size );
/* Number of samples written to output since it was last set, always
a multiple of 2. Undefined if more samples were generated than
output buffer could hold. */
int spc_dsp_sample_count( SPC_DSP const* );
/**** Emulation *****/
/* Resets DSP to power-on state */
void spc_dsp_reset( SPC_DSP* );
/* Emulates pressing reset switch on SNES */
void spc_dsp_soft_reset( SPC_DSP* );
/* Reads/writes DSP registers. For accuracy, you must first call spc_dsp_run() */
/* to catch the DSP up to present. */
int spc_dsp_read ( SPC_DSP const*, int addr );
void spc_dsp_write( SPC_DSP*, int addr, int data );
/* Runs DSP for specified number of clocks (~1024000 per second). Every 32 clocks */
/* a pair of samples is be generated. */
void spc_dsp_run( SPC_DSP*, int clock_count );
/**** Sound control *****/
/* Mutes voices corresponding to non-zero bits in mask. Reduces emulation accuracy. */
enum { spc_dsp_voice_count = 8 };
void spc_dsp_mute_voices( SPC_DSP*, int mask );
/* If true, prevents channels and global volumes from being phase-negated.
Only supported by fast DSP; has no effect on accurate DSP. */
void spc_dsp_disable_surround( SPC_DSP*, int disable );
/**** State save/load *****/
/* Resets DSP and uses supplied values to initialize registers */
enum { spc_dsp_register_count = 128 };
void spc_dsp_load( SPC_DSP*, unsigned char const regs [spc_dsp_register_count] );
/* Saves/loads exact emulator state (accurate DSP only) */
enum { spc_dsp_state_size = 640 }; /* maximum space needed when saving */
typedef void (*spc_dsp_copy_func_t)( unsigned char** io, void* state, size_t );
void spc_dsp_copy_state( SPC_DSP*, unsigned char** io, spc_dsp_copy_func_t );
/* Returns non-zero if new key-on events occurred since last call (accurate DSP only) */
int spc_dsp_check_kon( SPC_DSP* );
#ifdef __cplusplus
}
#endif
#endif