snes9xgx/source/snes9x/apu/apu.cpp
2019-04-12 13:24:23 -06:00

633 lines
15 KiB
C++

/*****************************************************************************\
Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
This file is licensed under the Snes9x License.
For further information, consult the LICENSE file in the root directory.
\*****************************************************************************/
#include <math.h>
#include "../snes9x.h"
#include "apu.h"
#include "../msu1.h"
#include "../snapshot.h"
#include "../display.h"
#include "resampler.h"
#define APU_DEFAULT_INPUT_RATE 32040
#define APU_MINIMUM_SAMPLE_COUNT 512
#define APU_MINIMUM_SAMPLE_BLOCK 128
#define APU_NUMERATOR_NTSC 15664
#define APU_DENOMINATOR_NTSC 328125
#define APU_NUMERATOR_PAL 34176
#define APU_DENOMINATOR_PAL 709379
SNES_SPC *spc_core = NULL;
static uint8 APUROM[64] =
{
0xCD, 0xEF, 0xBD, 0xE8, 0x00, 0xC6, 0x1D, 0xD0,
0xFC, 0x8F, 0xAA, 0xF4, 0x8F, 0xBB, 0xF5, 0x78,
0xCC, 0xF4, 0xD0, 0xFB, 0x2F, 0x19, 0xEB, 0xF4,
0xD0, 0xFC, 0x7E, 0xF4, 0xD0, 0x0B, 0xE4, 0xF5,
0xCB, 0xF4, 0xD7, 0x00, 0xFC, 0xD0, 0xF3, 0xAB,
0x01, 0x10, 0xEF, 0x7E, 0xF4, 0x10, 0xEB, 0xBA,
0xF6, 0xDA, 0x00, 0xBA, 0xF4, 0xC4, 0xF4, 0xDD,
0x5D, 0xD0, 0xDB, 0x1F, 0x00, 0x00, 0xC0, 0xFF
};
namespace spc
{
static apu_callback sa_callback = NULL;
static void *extra_data = NULL;
static bool8 sound_in_sync = TRUE;
static bool8 sound_enabled = FALSE;
static int buffer_size;
static int lag_master = 0;
static int lag = 0;
static uint8 *landing_buffer = NULL;
static uint8 *shrink_buffer = NULL;
static Resampler *resampler = NULL;
static int32 reference_time;
static uint32 remainder;
static const int timing_hack_numerator = SNES_SPC::tempo_unit;
static int timing_hack_denominator = SNES_SPC::tempo_unit;
/* Set these to NTSC for now. Will change to PAL in S9xAPUTimingSetSpeedup
if necessary on game load. */
static uint32 ratio_numerator = APU_NUMERATOR_NTSC;
static uint32 ratio_denominator = APU_DENOMINATOR_NTSC;
static double dynamic_rate_multiplier = 1.0;
} // namespace spc
namespace msu
{
static int buffer_size;
static uint8 *landing_buffer = NULL;
static Resampler *resampler = NULL;
static int resample_buffer_size = -1;
static uint8 *resample_buffer = NULL;
} // namespace msu
static void EightBitize (uint8 *, int);
static void DeStereo (uint8 *, int);
static void ReverseStereo (uint8 *, int);
void UpdatePlaybackRate (void);
static void from_apu_to_state (uint8 **, void *, size_t);
static void to_apu_from_state (uint8 **, void *, size_t);
static void SPCSnapshotCallback (void);
static inline int S9xAPUGetClock (int32);
static inline int S9xAPUGetClockRemainder (int32);
static void EightBitize (uint8 *buffer, int sample_count)
{
uint8 *buf8 = (uint8 *) buffer;
int16 *buf16 = (int16 *) buffer;
for (int i = 0; i < sample_count; i++)
buf8[i] = (uint8) ((buf16[i] / 256) + 128);
}
static void DeStereo (uint8 *buffer, int sample_count)
{
int16 *buf = (int16 *) buffer;
int32 s1, s2;
for (int i = 0; i < (sample_count >> 1); i++)
{
s1 = (int32) buf[2 * i];
s2 = (int32) buf[2 * i + 1];
buf[i] = (int16) ((s1 + s2) >> 1);
}
}
static void ReverseStereo (uint8 *src_buffer, int sample_count)
{
int16 *buffer = (int16 *) src_buffer;
for (int i = 0; i < sample_count; i += 2)
{
buffer[i + 1] ^= buffer[i];
buffer[i] ^= buffer[i + 1];
buffer[i + 1] ^= buffer[i];
}
}
bool8 S9xMixSamples (uint8 *buffer, int sample_count)
{
static int shrink_buffer_size = -1;
uint8 *dest;
if (!Settings.SixteenBitSound || !Settings.Stereo)
{
/* We still need both stereo samples for generating the mono sample */
if (!Settings.Stereo)
sample_count <<= 1;
/* We still have to generate 16-bit samples for bit-dropping, too */
if (shrink_buffer_size < (sample_count << 1))
{
delete[] spc::shrink_buffer;
spc::shrink_buffer = new uint8[sample_count << 1];
shrink_buffer_size = sample_count << 1;
}
dest = spc::shrink_buffer;
}
else
dest = buffer;
if (Settings.MSU1 && msu::resample_buffer_size < (sample_count << 3))
{
delete[] msu::resample_buffer;
msu::resample_buffer = new uint8[sample_count << 3];
msu::resample_buffer_size = sample_count << 3;
}
if (Settings.Mute)
{
memset(dest, 0, sample_count << 1);
spc::resampler->clear();
if(Settings.MSU1)
msu::resampler->clear();
return (FALSE);
}
else
{
if (spc::resampler->avail() >= (sample_count + spc::lag))
{
spc::resampler->read((short *) dest, sample_count);
if (spc::lag == spc::lag_master)
spc::lag = 0;
if (Settings.MSU1)
{
if (msu::resampler->avail() >= sample_count)
{
msu::resampler->read((short *)msu::resample_buffer, sample_count);
for (int32 i = 0; i < sample_count; ++i)
*((int16*)(dest+(i * 2))) += *((int16*)(msu::resample_buffer+(i * 2)));
}
}
}
else
{
memset(buffer, (Settings.SixteenBitSound ? 0 : 128), (sample_count << (Settings.SixteenBitSound ? 1 : 0)) >> (Settings.Stereo ? 0 : 1));
if (spc::lag == 0)
spc::lag = spc::lag_master;
return (FALSE);
}
}
if (Settings.ReverseStereo && Settings.Stereo)
ReverseStereo(dest, sample_count);
if (!Settings.Stereo || !Settings.SixteenBitSound)
{
if (!Settings.Stereo)
{
DeStereo(dest, sample_count);
sample_count >>= 1;
}
if (!Settings.SixteenBitSound)
EightBitize(dest, sample_count);
memcpy(buffer, dest, (sample_count << (Settings.SixteenBitSound ? 1 : 0)));
}
return (TRUE);
}
int S9xGetSampleCount (void)
{
return (spc::resampler->avail() >> (Settings.Stereo ? 0 : 1));
}
void S9xFinalizeSamples (void)
{
bool drop_current_msu1_samples = TRUE;
if (!Settings.Mute)
{
drop_current_msu1_samples = FALSE;
if (!spc::resampler->push((short *) spc::landing_buffer, spc_core->sample_count()))
{
/* We weren't able to process the entire buffer. Potential overrun. */
spc::sound_in_sync = FALSE;
if (Settings.SoundSync && !Settings.TurboMode)
return;
// since we drop the current dsp samples we also want to drop generated msu1 samples
drop_current_msu1_samples = TRUE;
}
}
// only generate msu1 if we really consumed the dsp samples (sample_count() resets at end of function),
// otherwise we will generate multiple times for the same samples - so this needs to be after all early
// function returns
if (Settings.MSU1)
{
// generate the same number of msu1 samples as dsp samples were generated
S9xMSU1SetOutput((int16 *)msu::landing_buffer, msu::buffer_size);
S9xMSU1Generate(spc_core->sample_count());
if (!drop_current_msu1_samples && !msu::resampler->push((short *)msu::landing_buffer, S9xMSU1Samples()))
{
// should not occur, msu buffer is larger and we drop msu samples if spc buffer overruns
}
}
if (!Settings.SoundSync || Settings.TurboMode || Settings.Mute)
spc::sound_in_sync = TRUE;
else
if (spc::resampler->space_empty() >= spc::resampler->space_filled())
spc::sound_in_sync = TRUE;
else
spc::sound_in_sync = FALSE;
spc_core->set_output((SNES_SPC::sample_t *) spc::landing_buffer, spc::buffer_size >> 1);
}
void S9xLandSamples (void)
{
if (spc::sa_callback != NULL)
spc::sa_callback(spc::extra_data);
else
S9xFinalizeSamples();
}
void S9xClearSamples (void)
{
spc::resampler->clear();
if (Settings.MSU1)
msu::resampler->clear();
spc::lag = spc::lag_master;
}
bool8 S9xSyncSound (void)
{
if (!Settings.SoundSync || spc::sound_in_sync)
return (TRUE);
S9xLandSamples();
return (spc::sound_in_sync);
}
void S9xSetSamplesAvailableCallback (apu_callback callback, void *data)
{
spc::sa_callback = callback;
spc::extra_data = data;
}
void S9xUpdateDynamicRate (double rate)
{
if(spc::dynamic_rate_multiplier != rate) {
spc::dynamic_rate_multiplier = rate;
UpdatePlaybackRate();
}
}
void UpdatePlaybackRate (void)
{
if (Settings.SoundInputRate == 0)
Settings.SoundInputRate = APU_DEFAULT_INPUT_RATE;
double time_ratio = (double) Settings.SoundInputRate * spc::timing_hack_numerator / (Settings.SoundPlaybackRate * spc::timing_hack_denominator);
if (Settings.DynamicRateControl)
{
time_ratio *= spc::dynamic_rate_multiplier;
}
spc::resampler->time_ratio(time_ratio);
if (Settings.MSU1)
{
time_ratio = (44100.0 / Settings.SoundPlaybackRate) * (Settings.SoundInputRate / 32040.0);
msu::resampler->time_ratio(time_ratio);
}
}
bool8 S9xInitSound (int buffer_ms, int lag_ms)
{
// buffer_ms : buffer size given in millisecond
// lag_ms : allowable time-lag given in millisecond
int sample_count = buffer_ms * 32040 / 1000;
int lag_sample_count = lag_ms * 32040 / 1000;
spc::lag_master = lag_sample_count;
if (Settings.Stereo)
spc::lag_master <<= 1;
spc::lag = spc::lag_master;
if (sample_count < APU_MINIMUM_SAMPLE_COUNT)
sample_count = APU_MINIMUM_SAMPLE_COUNT;
spc::buffer_size = sample_count;
if (Settings.Stereo)
spc::buffer_size <<= 1;
if (Settings.SixteenBitSound)
spc::buffer_size <<= 1;
msu::buffer_size = sample_count << 3; // Always 16-bit, Stereo; x2 to never overflow before dsp buffer
printf("Sound buffer size: %d (%d samples)\n", spc::buffer_size, sample_count);
if (spc::landing_buffer)
delete[] spc::landing_buffer;
spc::landing_buffer = new uint8[spc::buffer_size * 2];
if (!spc::landing_buffer)
return (FALSE);
if (msu::landing_buffer)
delete[] msu::landing_buffer;
msu::landing_buffer = (uint8*) new uint32[msu::buffer_size / 2]; // Ensure 4-byte alignment
if (!msu::landing_buffer)
return (FALSE);
/* The resampler and spc unit use samples (16-bit short) as
arguments. Use 2x in the resampler for buffer leveling with SoundSync */
if (!spc::resampler)
{
spc::resampler = new Resampler(spc::buffer_size >> (Settings.SoundSync ? 0 : 1));
if (!spc::resampler)
{
delete[] spc::landing_buffer;
return (FALSE);
}
}
else
spc::resampler->resize(spc::buffer_size >> (Settings.SoundSync ? 0 : 1));
if (!msu::resampler)
{
msu::resampler = new Resampler(msu::buffer_size >> (Settings.SoundSync ? 0 : 1));
if (!msu::resampler)
{
delete[] msu::landing_buffer;
return (FALSE);
}
}
else
msu::resampler->resize(msu::buffer_size);
spc_core->set_output((SNES_SPC::sample_t *) spc::landing_buffer, spc::buffer_size >> 1);
UpdatePlaybackRate();
spc::sound_enabled = S9xOpenSoundDevice();
return (spc::sound_enabled);
}
void S9xSetSoundControl (uint8 voice_switch)
{
spc_core->dsp_set_stereo_switch(voice_switch << 8 | voice_switch);
}
void S9xSetSoundMute (bool8 mute)
{
Settings.Mute = mute;
if (!spc::sound_enabled)
Settings.Mute = TRUE;
}
void S9xDumpSPCSnapshot (void)
{
spc_core->dsp_dump_spc_snapshot();
}
static void SPCSnapshotCallback (void)
{
S9xSPCDump(S9xGetFilenameInc((".spc"), SPC_DIR));
printf("Dumped key-on triggered spc snapshot.\n");
}
bool8 S9xInitAPU (void)
{
spc_core = new SNES_SPC;
if (!spc_core)
return (FALSE);
spc_core->init();
spc_core->init_rom(APUROM);
spc_core->dsp_set_spc_snapshot_callback(SPCSnapshotCallback);
spc::landing_buffer = NULL;
spc::shrink_buffer = NULL;
spc::resampler = NULL;
msu::resampler = NULL;
return (TRUE);
}
void S9xDeinitAPU (void)
{
if (spc_core)
{
delete spc_core;
spc_core = NULL;
}
if (spc::resampler)
{
delete spc::resampler;
spc::resampler = NULL;
}
if (spc::landing_buffer)
{
delete[] spc::landing_buffer;
spc::landing_buffer = NULL;
}
if (spc::shrink_buffer)
{
delete[] spc::shrink_buffer;
spc::shrink_buffer = NULL;
}
if (msu::resampler)
{
delete msu::resampler;
msu::resampler = NULL;
}
if (msu::landing_buffer)
{
delete[] msu::landing_buffer;
msu::landing_buffer = NULL;
}
if (msu::resample_buffer)
{
delete[] msu::resample_buffer;
msu::resample_buffer = NULL;
}
S9xMSU1DeInit();
}
static inline int S9xAPUGetClock (int32 cpucycles)
{
return (spc::ratio_numerator * (cpucycles - spc::reference_time) + spc::remainder) /
spc::ratio_denominator;
}
static inline int S9xAPUGetClockRemainder (int32 cpucycles)
{
return (spc::ratio_numerator * (cpucycles - spc::reference_time) + spc::remainder) %
spc::ratio_denominator;
}
uint8 S9xAPUReadPort (int port)
{
return ((uint8) spc_core->read_port(S9xAPUGetClock(CPU.Cycles), port));
}
void S9xAPUWritePort (int port, uint8 byte)
{
spc_core->write_port(S9xAPUGetClock(CPU.Cycles), port, byte);
}
void S9xAPUSetReferenceTime (int32 cpucycles)
{
spc::reference_time = cpucycles;
}
void S9xAPUExecute (void)
{
/* Accumulate partial APU cycles */
spc_core->end_frame(S9xAPUGetClock(CPU.Cycles));
spc::remainder = S9xAPUGetClockRemainder(CPU.Cycles);
S9xAPUSetReferenceTime(CPU.Cycles);
}
void S9xAPUEndScanline (void)
{
S9xAPUExecute();
if (spc_core->sample_count() >= APU_MINIMUM_SAMPLE_BLOCK || !spc::sound_in_sync)
S9xLandSamples();
}
void S9xAPUTimingSetSpeedup (int ticks)
{
if (ticks != 0)
printf("APU speedup hack: %d\n", ticks);
spc::timing_hack_denominator = SNES_SPC::tempo_unit - ticks;
spc_core->set_tempo(spc::timing_hack_denominator);
spc::ratio_numerator = Settings.PAL ? APU_NUMERATOR_PAL : APU_NUMERATOR_NTSC;
spc::ratio_denominator = Settings.PAL ? APU_DENOMINATOR_PAL : APU_DENOMINATOR_NTSC;
spc::ratio_denominator = spc::ratio_denominator * spc::timing_hack_denominator / spc::timing_hack_numerator;
UpdatePlaybackRate();
}
void S9xAPUAllowTimeOverflow (bool allow)
{
spc_core->spc_allow_time_overflow(allow);
}
void S9xResetAPU (void)
{
spc::reference_time = 0;
spc::remainder = 0;
spc_core->reset();
spc_core->set_output((SNES_SPC::sample_t *) spc::landing_buffer, spc::buffer_size >> 1);
spc::resampler->clear();
if (Settings.MSU1)
msu::resampler->clear();
}
void S9xSoftResetAPU (void)
{
spc::reference_time = 0;
spc::remainder = 0;
spc_core->soft_reset();
spc_core->set_output((SNES_SPC::sample_t *) spc::landing_buffer, spc::buffer_size >> 1);
spc::resampler->clear();
if (Settings.MSU1)
msu::resampler->clear();
}
static void from_apu_to_state (uint8 **buf, void *var, size_t size)
{
memcpy(*buf, var, size);
*buf += size;
}
static void to_apu_from_state (uint8 **buf, void *var, size_t size)
{
memcpy(var, *buf, size);
*buf += size;
}
void S9xAPUSaveState (uint8 *block)
{
uint8 *ptr = block;
spc_core->copy_state(&ptr, from_apu_to_state);
SET_LE32(ptr, spc::reference_time);
ptr += sizeof(int32);
SET_LE32(ptr, spc::remainder);
}
void S9xAPULoadState (uint8 *block)
{
uint8 *ptr = block;
S9xResetAPU();
spc_core->copy_state(&ptr, to_apu_from_state);
spc::reference_time = GET_LE32(ptr);
ptr += sizeof(int32);
spc::remainder = GET_LE32(ptr);
}
bool8 S9xSPCDump (const char *filename)
{
FILE *fs;
uint8 buf[SNES_SPC::spc_file_size];
size_t ignore;
fs = fopen(filename, "wb");
if (!fs)
return (FALSE);
S9xSetSoundMute(TRUE);
spc_core->init_header(buf);
spc_core->save_spc(buf);
ignore = fwrite(buf, SNES_SPC::spc_file_size, 1, fs);
fclose(fs);
S9xSetSoundMute(FALSE);
return (TRUE);
}