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optimized sound chips update functions

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This commit is contained in:
ekeeke31 2012-01-15 19:57:59 +00:00
parent 873870b4a1
commit 238382d8a8
2 changed files with 24 additions and 44 deletions
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66
source/sound/sound.c
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@ -52,71 +52,49 @@ static void (*YM_Update)(int *buffer, int length);
static void (*YM_Write)(unsigned int a, unsigned int v); static void (*YM_Write)(unsigned int a, unsigned int v);
/* Run FM chip for required M-cycles */ /* Run FM chip for required M-cycles */
static inline void fm_update(unsigned int cycles) static __inline__ void fm_update(unsigned int cycles)
{ {
if (cycles > fm_cycles_count) if (cycles > fm_cycles_count)
{ {
/* period to run */ int32 *buffer;
cycles -= fm_cycles_count;
/* samples to run */
unsigned int samples = (cycles - fm_cycles_count + fm_cycles_ratio - 1) / fm_cycles_ratio;
/* update cycle count */ /* update cycle count */
fm_cycles_count += cycles; fm_cycles_count += samples * fm_cycles_ratio;
/* number of samples during period */
unsigned int cnt = cycles / fm_cycles_ratio;
/* remaining cycles */
unsigned int remain = cycles % fm_cycles_ratio;
if (remain)
{
/* one sample ahead */
fm_cycles_count += fm_cycles_ratio - remain;
cnt++;
}
/* select input sample buffer */ /* select input sample buffer */
int32 *buffer = Fir_Resampler_buffer(); buffer = Fir_Resampler_buffer();
if (buffer) if (buffer)
{ {
Fir_Resampler_write(cnt << 1); Fir_Resampler_write(samples << 1);
} }
else else
{ {
buffer = snd.fm.pos; buffer = snd.fm.pos;
snd.fm.pos += (cnt << 1); snd.fm.pos += (samples << 1);
} }
/* run FM chip & get samples */ /* run FM chip & get samples */
YM_Update(buffer, cnt); YM_Update(buffer, samples);
} }
} }
/* Run PSG chip for required M-cycles */ /* Run PSG chip for required M-cycles */
static inline void psg_update(unsigned int cycles) static __inline__ void psg_update(unsigned int cycles)
{ {
if (cycles > psg_cycles_count) if (cycles > psg_cycles_count)
{ {
/* period to run */ /* samples to run */
cycles -= psg_cycles_count; unsigned int samples = (cycles - psg_cycles_count + psg_cycles_ratio - 1) / psg_cycles_ratio;
/* update cycle count */ /* update cycle count */
psg_cycles_count += cycles; psg_cycles_count += samples * psg_cycles_ratio;
/* number of samples during period */
unsigned int cnt = cycles / psg_cycles_ratio;
/* remaining cycles */
unsigned int remain = cycles % psg_cycles_ratio;
if (remain)
{
/* one sample ahead */
psg_cycles_count += psg_cycles_ratio - remain;
cnt++;
}
/* run PSG chip & get samples */ /* run PSG chip & get samples */
SN76489_Update(snd.psg.pos, cnt); SN76489_Update(snd.psg.pos, samples);
snd.psg.pos += cnt; snd.psg.pos += samples;
} }
} }
@ -262,11 +240,11 @@ int sound_context_save(uint8 *state)
return bufferptr; return bufferptr;
} }
int sound_context_load(uint8 *state, char *version) int sound_context_load(uint8 *state)
{ {
int bufferptr = 0; int bufferptr = 0;
if (((system_hw & SYSTEM_PBC) == SYSTEM_MD) || ((version[13] == 0x35) && (version[15] == 0x30))) if ((system_hw & SYSTEM_PBC) == SYSTEM_MD)
{ {
bufferptr = YM2612LoadContext(state); bufferptr = YM2612LoadContext(state);
} }
@ -287,15 +265,17 @@ int sound_context_load(uint8 *state, char *version)
/* End of frame update, return the number of samples run so far. */ /* End of frame update, return the number of samples run so far. */
int sound_update(unsigned int cycles) int sound_update(unsigned int cycles)
{ {
int size;
/* run PSG & FM chips until end of frame */ /* run PSG & FM chips until end of frame */
cycles <<= 11; cycles <<= 11;
psg_update(cycles); psg_update(cycles);
fm_update(cycles); fm_update(cycles);
int size = snd.psg.pos - snd.psg.buffer; /* available PSG samples */
size = snd.psg.pos - snd.psg.buffer;
#ifdef LOGSOUND #ifdef LOGSOUND
error("%d PSG samples available\n",size); error("%d PSG samples available\n",size);
#endif #endif
/* FM resampling */ /* FM resampling */

2
source/sound/sound.h
View File

@ -45,7 +45,7 @@ extern void sound_init(void);
extern void sound_reset(void); extern void sound_reset(void);
extern void sound_restore(void); extern void sound_restore(void);
extern int sound_context_save(uint8 *state); extern int sound_context_save(uint8 *state);
extern int sound_context_load(uint8 *state, char *version); extern int sound_context_load(uint8 *state);
extern int sound_update(unsigned int cycles); extern int sound_update(unsigned int cycles);
extern void fm_reset(unsigned int cycles); extern void fm_reset(unsigned int cycles);
extern void fm_write(unsigned int cycles, unsigned int address, unsigned int data); extern void fm_write(unsigned int cycles, unsigned int address, unsigned int data);