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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);
/* 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)
{
/* period to run */
cycles -= fm_cycles_count;
int32 *buffer;
/* samples to run */
unsigned int samples = (cycles - fm_cycles_count + fm_cycles_ratio - 1) / fm_cycles_ratio;
/* update cycle count */
fm_cycles_count += cycles;
/* 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++;
}
fm_cycles_count += samples * fm_cycles_ratio;
/* select input sample buffer */
int32 *buffer = Fir_Resampler_buffer();
buffer = Fir_Resampler_buffer();
if (buffer)
{
Fir_Resampler_write(cnt << 1);
Fir_Resampler_write(samples << 1);
}
else
{
buffer = snd.fm.pos;
snd.fm.pos += (cnt << 1);
snd.fm.pos += (samples << 1);
}
/* run FM chip & get samples */
YM_Update(buffer, cnt);
YM_Update(buffer, samples);
}
}
/* 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)
{
/* period to run */
cycles -= psg_cycles_count;
/* samples to run */
unsigned int samples = (cycles - psg_cycles_count + psg_cycles_ratio - 1) / psg_cycles_ratio;
/* update cycle count */
psg_cycles_count += cycles;
/* 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++;
}
psg_cycles_count += samples * psg_cycles_ratio;
/* run PSG chip & get samples */
SN76489_Update(snd.psg.pos, cnt);
snd.psg.pos += cnt;
SN76489_Update(snd.psg.pos, samples);
snd.psg.pos += samples;
}
}
@ -262,11 +240,11 @@ int sound_context_save(uint8 *state)
return bufferptr;
}
int sound_context_load(uint8 *state, char *version)
int sound_context_load(uint8 *state)
{
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);
}
@ -287,15 +265,17 @@ int sound_context_load(uint8 *state, char *version)
/* End of frame update, return the number of samples run so far. */
int sound_update(unsigned int cycles)
{
int size;
/* run PSG & FM chips until end of frame */
cycles <<= 11;
psg_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
error("%d PSG samples available\n",size);
error("%d PSG samples available\n",size);
#endif
/* 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_restore(void);
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 void fm_reset(unsigned int cycles);
extern void fm_write(unsigned int cycles, unsigned int address, unsigned int data);