ref: 6155437096ad7fd125b8cde49c1c344d7bb6f312
dir: /src/pt2_sync.c/
#include <stdint.h> #include <stdbool.h> #include "pt2_header.h" #include "pt2_sync.h" #include "pt2_scopes.h" #include "pt2_audio.h" #include "pt2_visuals.h" #include "pt2_tables.h" static volatile bool chQueueClearing; chSyncData_t *chSyncEntry; // globalized chSync_t chSync; // globalized 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 updateChannelSyncBuffer(void) { uint8_t updateFlags[AMIGA_VOICES]; chSyncEntry = NULL; memset(updateFlags, 0, sizeof (updateFlags)); // 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 < AMIGA_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 < AMIGA_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); if (flags & TRIGGER_SCOPE) { s->newData = c->triggerData; s->newLength = c->triggerLength; scopeTrigger(ch); } if (flags & SET_SCOPE_DATA) scope[ch].newData = c->newData; if (flags & SET_SCOPE_LENGTH) scope[ch].newLength = c->newLength; if (flags & STOP_SCOPE) scope[ch].active = false; 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]; } } } }