Global buffer and ABL fixes

wled00/FX_fcn.cpp

@@ -1209,7 +1209,13 @@ uint8_t WS2812FX::estimateCurrentAndLimitBri() {
     uint16_t len = bus->getLength();
     uint32_t busPowerSum = 0;
     for (uint_fast16_t i = 0; i < len; i++) { //sum up the usage of each LED
-      uint32_t c = bus->getPixelColor(i);
+      uint32_t c = 0;
+      if (_globalLedBuffer)
+      {
+        c = _globalLedBuffer[bus->getStart() + i];
+      } else {
+        c = bus->getPixelColor(i);
+      }
       byte r = R(c), g = G(c), b = B(c), w = W(c);
 
       if(useWackyWS2815PowerModel) { //ignore white component on WS2815 power calculation
@@ -1253,14 +1259,16 @@ void WS2812FX::show(void) {
   show_callback callback = _callback;
   if (callback) callback();
 
+  Bus::setRestoreBri(_renderBrightness);
   uint8_t busBrightness = estimateCurrentAndLimitBri();
 
   if (_globalLedBuffer) { // copy data from buffer to bus
     for (uint16_t i = 0; i < _length; i++) busses.setPixelColor(i, _globalLedBuffer[i]);
   } else {
     // if brightness changed since last show, must set everything again to update to new luminance
     if (_renderBrightness != busBrightness) {
-      for (uint16_t i = 0; i < _length; i++) busses.setPixelColor(i, busses.getPixelColor(i)); // LOSSY and slow!
+      for (uint16_t i = 0; i < _length; i++) busses.setPixelColor(i, busses.getPixelColor(i)); // LOSSLESS due to trick (but still slow!)
+      Bus::setRestoreBri(busBrightness);
     }
   }
 
@@ -1343,6 +1351,7 @@ void WS2812FX::setBrightness(uint8_t b, bool direct) {
     // would be dangerous if applied immediately (could exceed ABL), but will not output until the next show()
     busses.setBrightness(b);
     _renderBrightness = b;
+    Bus::setRestoreBri(b);
   } else {
     unsigned long t = millis();
     if (_segments[0].next_time > t + 22 && t - _lastShow > MIN_SHOW_DELAY) show(); //apply brightness change immediately if no refresh soon

wled00/bus_manager.cpp

@@ -563,3 +563,4 @@ uint16_t BusManager::getTotalLength() {
 int16_t Bus::_cct = -1;
 uint8_t Bus::_cctBlend = 0;
 uint8_t Bus::_gAWM = 255;
+uint8_t Bus::_restaurationBri = 255;

wled00/bus_manager.h

@@ -154,6 +154,7 @@ class Bus {
     inline        uint8_t getAutoWhiteMode()          { return _autoWhiteMode; }
     inline static void    setGlobalAWMode(uint8_t m)  { if (m < 5) _gAWM = m; else _gAWM = AW_GLOBAL_DISABLED; }
     inline static uint8_t getGlobalAWMode()           { return _gAWM; }
+    inline static void    setRestoreBri(uint8_t b)    { _restaurationBri = b; }
 
     bool reversed = false;
 
@@ -168,6 +169,7 @@ class Bus {
     static uint8_t _gAWM;
     static int16_t _cct;
     static uint8_t _cctBlend;
+    static uint8_t _restaurationBri; // previous brightness used as setPixelColor was called. Used for lossy restoration
 
     uint32_t autoWhiteCalc(uint32_t c);
 };
@@ -231,7 +233,7 @@ class BusDigital : public Bus {
       for (uint8_t i=0; i<4; i++)
       {
         uint16_t val = chan[i];
-        chan[i] = (val << 8) / (_bri + 1);
+        chan[i] = ((val << 8) + _restaurationBri) / (_restaurationBri + 1); //adding _bri slighly improves recovery / stops degradation on re-scale
       }
       return c;
     }

wled00/cfg.cpp

@@ -134,7 +134,8 @@ bool deserializeConfig(JsonObject doc, bool fromFS) {
   if (fromFS || !ins.isNull()) {
     uint8_t s = 0;  // bus iterator
     if (fromFS) busses.removeAll(); // can't safely manipulate busses directly in network callback
-    uint32_t mem = 0;
+    uint32_t mem = 0, globalBufMem = 0;
+    uint16_t maxlen = 0;
     bool busesChanged = false;
     for (JsonObject elm : ins) {
       if (s >= WLED_MAX_BUSSES+WLED_MIN_VIRTUAL_BUSSES) break;
@@ -162,7 +163,11 @@ bool deserializeConfig(JsonObject doc, bool fromFS) {
       if (fromFS) {
         BusConfig bc = BusConfig(ledType, pins, start, length, colorOrder, reversed, skipFirst, AWmode, freqkHz);
         mem += BusManager::memUsage(bc);
-        if (mem <= MAX_LED_MEMORY) if (busses.add(bc) == -1) break;  // finalization will be done in WLED::beginStrip()
+        if (strip.useGlobalLedBuffer && start + length > maxlen) {
+          maxlen = start + length;
+          globalBufMem = maxlen * 4;
+        }
+        if (mem + globalBufMem <= MAX_LED_MEMORY) if (busses.add(bc) == -1) break;  // finalization will be done in WLED::beginStrip()
       } else {
         if (busConfigs[s] != nullptr) delete busConfigs[s];
         busConfigs[s] = new BusConfig(ledType, pins, start, length, colorOrder, reversed, skipFirst, AWmode);

wled00/data/settings_leds.htm

@@ -141,7 +141,7 @@
 			let len = parseInt(d.getElementsByName("LC"+n)[0].value);
 			len += parseInt(d.getElementsByName("SL"+n)[0].value); // skipped LEDs are allocated too
 			let dbl = 0;
-			if (d.Sf.LD.checked) dbl = len * 3;	// double buffering
+			if (d.Sf.LD.checked) dbl = len * 4;	// double buffering
 			if (t < 32) {
 				if (t==26 || t==29) len *= 2; // 16 bit LEDs
 				if (maxM < 10000 && d.getElementsByName("L0"+n)[0].value == 3) { //8266 DMA uses 5x the mem

wled00/wled.cpp

@@ -151,11 +151,16 @@ void WLED::loop()
     DEBUG_PRINTLN(F("Re-init busses."));
     bool aligned = strip.checkSegmentAlignment(); //see if old segments match old bus(ses)
     busses.removeAll();
-    uint32_t mem = 0;
+    uint32_t mem = 0, globalBufMem = 0;
+    uint16_t maxlen = 0;
     for (uint8_t i = 0; i < WLED_MAX_BUSSES+WLED_MIN_VIRTUAL_BUSSES; i++) {
       if (busConfigs[i] == nullptr) break;
       mem += BusManager::memUsage(*busConfigs[i]);
-      if (mem <= MAX_LED_MEMORY) {
+      if (strip.useGlobalLedBuffer && busConfigs[i]->start + busConfigs[i]->count > maxlen) {
+          maxlen = busConfigs[i]->start + busConfigs[i]->count;
+          globalBufMem = maxlen * 4;
+      }
+      if (mem + globalBufMem <= MAX_LED_MEMORY) {
         busses.add(*busConfigs[i]);
       }
       delete busConfigs[i]; busConfigs[i] = nullptr;