ref: 88b781094d31f244b52a420330ec8049d7ca7b36
dir: /src/pt2_visuals_sync.c/
// used for syncing audio from Paula writes to tracker visuals
#include <stdint.h>
#include <stdbool.h>
#include "pt2_audio.h"
#include "pt2_visuals_sync.h"
#include "pt2_scopes.h"
#include "pt2_visuals.h"
#include "pt2_tables.h"
typedef struct syncVoice_t
{
const int8_t *newData, *data;
uint8_t flags, volume;
uint16_t period;
uint16_t newLength, length;
} syncVoice_t;
static volatile bool chQueueClearing;
static uint32_t audLatencyPerfValInt, audLatencyPerfValFrac;
static uint64_t tickTime64, tickTime64Frac;
static uint32_t tickTimeLen, tickTimeLenFrac;
static syncVoice_t syncVoice[PAULA_VOICES];
static chSyncData_t *chSyncEntry;
static chSync_t chSync;
static void startDMA(int32_t ch)
{
syncVoice_t *sv = &syncVoice[ch];
if (editor.songPlaying)
{
sv->data = sv->newData;
sv->length = sv->newLength;
sv->flags |= TRIGGER_SCOPE;
}
else
{
scope_t *s = &scope[ch];
s->data = sv->newData;
s->length = sv->newLength * 2;
scopeTrigger(ch);
}
}
static void stopDMA(int32_t ch)
{
if (editor.songPlaying)
syncVoice[ch].flags |= STOP_SCOPE;
else
scope[ch].active = false;
}
void setVisualsDMACON(uint16_t bits)
{
if (bits & 0x8000)
{
// set
if (bits & 1) startDMA(0);
if (bits & 2) startDMA(1);
if (bits & 4) startDMA(2);
if (bits & 8) startDMA(3);
}
else
{
// clear
if (bits & 1) stopDMA(0);
if (bits & 2) stopDMA(1);
if (bits & 4) stopDMA(2);
if (bits & 8) stopDMA(3);
}
}
void setVisualsVolume(int32_t ch, uint16_t vol)
{
int32_t realVol = vol & 127;
if (realVol > 64)
realVol = 64;
if (editor.songPlaying)
{
syncVoice_t *sv = &syncVoice[ch];
sv->volume = (uint8_t)realVol;
sv->flags |= SET_SCOPE_VOLUME;
}
else
{
scope[ch].volume = (uint8_t)realVol;
}
}
void setVisualsPeriod(int32_t ch, uint16_t period)
{
if (period == 0)
period = 65535; // On Amiga: period 0 = one full cycle with period 65536, then period 65535 for the rest
else if (period < 113)
period = 113; // close to what happens on real Amiga (and needed for BLEP synthesis)
if (editor.songPlaying)
{
syncVoice_t *sv = &syncVoice[ch];
sv->period = period;
sv->flags |= SET_SCOPE_PERIOD;
}
else
{
scopeSetPeriod(ch, period);
}
}
void setVisualsLength(int32_t ch, uint16_t len)
{
syncVoice_t *sv = &syncVoice[ch];
sv->newLength = len;
if (editor.songPlaying)
sv->flags |= SET_SCOPE_LENGTH;
else
scope[ch].newLength = len * 2;
}
void setVisualsDataPtr(int32_t ch, const int8_t *src)
{
syncVoice_t *sv = &syncVoice[ch];
if (src == NULL)
src = paulaGetNullSamplePtr();
sv->newData = src;
if (editor.songPlaying)
sv->flags |= SET_SCOPE_DATA;
else
scope[ch].newData = src;
}
void calcAudioLatencyVars(int32_t audioBufferSize, int32_t audioFreq)
{
double dInt, dFrac;
if (audioFreq == 0)
return;
const double dAudioLatencySecs = audioBufferSize / (double)audioFreq;
dFrac = modf(dAudioLatencySecs * hpcFreq.dFreq, &dInt);
// integer part
audLatencyPerfValInt = (uint32_t)dInt;
// fractional part (scaled to 0..2^32-1)
audLatencyPerfValFrac = (uint32_t)((dFrac * (UINT32_MAX+1.0)) + 0.5); // rounded
}
void setSyncTickTimeLen(uint32_t timeLen, uint32_t timeLenFrac)
{
tickTimeLen = timeLen;
tickTimeLenFrac = timeLenFrac;
}
void resetChSyncQueue(void)
{
chSync.data[0].timestamp = 0;
chSync.writePos = 0;
chSync.readPos = 0;
}
static int32_t chQueueReadSize(void)
{
while (chQueueClearing);
if (chSync.writePos > chSync.readPos)
return chSync.writePos - chSync.readPos;
else if (chSync.writePos < chSync.readPos)
return chSync.writePos - chSync.readPos + SYNC_QUEUE_LEN + 1;
else
return 0;
}
static int32_t chQueueWriteSize(void)
{
int32_t size;
if (chSync.writePos > chSync.readPos)
{
size = chSync.readPos - chSync.writePos + SYNC_QUEUE_LEN;
}
else if (chSync.writePos < chSync.readPos)
{
chQueueClearing = true;
/* Buffer is full, reset the read/write pos. This is actually really nasty since
** read/write are two different threads, but because of timestamp validation it
** shouldn't be that dangerous.
** It will also create a small visual stutter while the buffer is getting filled,
** though that is barely noticable on normal buffer sizes, and it takes a minute
** or two at max BPM between each time (when queue size is default, 8191)
*/
chSync.data[0].timestamp = 0;
chSync.readPos = 0;
chSync.writePos = 0;
size = SYNC_QUEUE_LEN;
chQueueClearing = false;
}
else
{
size = SYNC_QUEUE_LEN;
}
return size;
}
bool chQueuePush(chSyncData_t t)
{
if (!chQueueWriteSize())
return false;
assert(chSync.writePos <= SYNC_QUEUE_LEN);
chSync.data[chSync.writePos] = t;
chSync.writePos = (chSync.writePos + 1) & SYNC_QUEUE_LEN;
return true;
}
static bool chQueuePop(void)
{
if (!chQueueReadSize())
return false;
chSync.readPos = (chSync.readPos + 1) & SYNC_QUEUE_LEN;
assert(chSync.readPos <= SYNC_QUEUE_LEN);
return true;
}
static chSyncData_t *chQueuePeek(void)
{
if (!chQueueReadSize())
return NULL;
assert(chSync.readPos <= SYNC_QUEUE_LEN);
return &chSync.data[chSync.readPos];
}
static uint64_t getChQueueTimestamp(void)
{
if (!chQueueReadSize())
return 0;
assert(chSync.readPos <= SYNC_QUEUE_LEN);
return chSync.data[chSync.readPos].timestamp;
}
void fillVisualsSyncBuffer(void)
{
chSyncData_t chSyncData;
if (audio.resetSyncTickTimeFlag)
{
audio.resetSyncTickTimeFlag = false;
tickTime64 = SDL_GetPerformanceCounter() + audLatencyPerfValInt;
tickTime64Frac = audLatencyPerfValFrac;
}
if (song != NULL)
{
moduleChannel_t *ch = song->channels;
syncVoice_t *sv = syncVoice;
syncedChannel_t *sc = chSyncData.channels;
for (int32_t i = 0; i < PAULA_VOICES; i++, ch++, sc++, sv++)
{
sc->flags = sv->flags | ch->syncFlags;
ch->syncFlags = sv->flags = 0; // clear sync flags
sc->volume = sv->volume;
sc->period = sv->period;
sc->data = sv->data;
sc->length = sv->length;
sc->newData = sv->newData;
sc->newLength = sv->newLength;
sc->vuVolume = ch->syncVuVolume;
sc->analyzerVolume = ch->syncAnalyzerVolume;
sc->analyzerPeriod = ch->syncAnalyzerPeriod;
}
chSyncData.timestamp = tickTime64;
chQueuePush(chSyncData);
}
tickTime64 += tickTimeLen;
tickTime64Frac += tickTimeLenFrac;
if (tickTime64Frac > UINT32_MAX)
{
tickTime64Frac &= UINT32_MAX;
tickTime64++;
}
}
void updateChannelSyncBuffer(void)
{
uint8_t updateFlags[PAULA_VOICES];
chSyncEntry = NULL;
*(uint32_t *)updateFlags = 0; // clear all channel update flags (this is needed)
const uint64_t frameTime64 = SDL_GetPerformanceCounter();
// handle channel sync queue
while (chQueueClearing);
while (chQueueReadSize() > 0)
{
if (frameTime64 < getChQueueTimestamp())
break; // we have no more stuff to render for now
chSyncEntry = chQueuePeek();
if (chSyncEntry == NULL)
break;
for (int32_t i = 0; i < PAULA_VOICES; i++)
updateFlags[i] |= chSyncEntry->channels[i].flags; // yes, OR the status
if (!chQueuePop())
break;
}
/* Extra validation because of possible issues when the buffer is full
** and positions are being reset, which is not entirely thread safe.
*/
if (chSyncEntry != NULL && chSyncEntry->timestamp == 0)
chSyncEntry = NULL;
// do actual updates
if (chSyncEntry != NULL)
{
scope_t *s = scope;
syncedChannel_t *c = chSyncEntry->channels;
for (int32_t ch = 0; ch < PAULA_VOICES; ch++, s++, c++)
{
const uint8_t flags = updateFlags[ch];
if (flags == 0)
continue;
if (flags & SET_SCOPE_VOLUME)
scope[ch].volume = c->volume;
if (flags & SET_SCOPE_PERIOD)
scopeSetPeriod(ch, c->period);
// the following handling order is important, don't change it!
if (flags & STOP_SCOPE)
scope[ch].active = false;
if (flags & TRIGGER_SCOPE)
{
s->data = c->data;
s->length = c->length * 2;
scopeTrigger(ch);
}
if (flags & SET_SCOPE_DATA)
scope[ch].newData = c->newData;
if (flags & SET_SCOPE_LENGTH)
scope[ch].newLength = c->newLength * 2;
// ---------------------------------------------------------------
if (flags & UPDATE_ANALYZER)
updateSpectrumAnalyzer(c->analyzerVolume, c ->analyzerPeriod);
if (flags & UPDATE_VUMETER) // for fake VU-meters only
{
if (c->vuVolume <= 64)
editor.vuMeterVolumes[ch] = vuMeterHeights[c->vuVolume];
}
}
}
}