Reduce segment copies

wled00/FX.h

@@ -626,7 +626,6 @@ typedef struct Segment {
     Segment &setMode(uint8_t fx, bool loadDefaults = false);
     Segment &setPalette(uint8_t pal);
     Segment &setName(const char* name);
-    uint8_t differs(const Segment& b) const;
     void    refreshLightCapabilities();
 
     // runtime data functions
@@ -883,7 +882,8 @@ class WS2812FX {  // 96 bytes
     inline void trigger()                                     { _triggered = true; }  // Forces the next frame to be computed on all active segments.
     inline void setShowCallback(show_callback cb)             { _callback = cb; }
     inline void setTransition(uint16_t t)                     { _transitionDur = t; } // sets transition time (in ms)
-    inline void appendSegment(const Segment &seg = Segment()) { if (_segments.size() < getMaxSegments()) _segments.push_back(seg); }
+    template<typename... Args>
+    inline void emplaceSegment(Args&&... args)                { if (_segments.size() < getMaxSegments()) _segments.emplace_back(std::forward<Args>(args)...); }
     inline void suspend()                                     { _suspend = true; }    // will suspend (and canacel) strip.service() execution
     inline void resume()                                      { _suspend = false; }   // will resume strip.service() execution
 

wled00/FX_fcn.cpp

@@ -1084,33 +1084,6 @@ uint32_t IRAM_ATTR_YN Segment::getPixelColor(int i) const
   return strip.getPixelColor(i);
 }
 
-uint8_t Segment::differs(const Segment& b) const {
-  uint8_t d = 0;
-  if (start != b.start)         d |= SEG_DIFFERS_BOUNDS;
-  if (stop != b.stop)           d |= SEG_DIFFERS_BOUNDS;
-  if (offset != b.offset)       d |= SEG_DIFFERS_GSO;
-  if (grouping != b.grouping)   d |= SEG_DIFFERS_GSO;
-  if (spacing != b.spacing)     d |= SEG_DIFFERS_GSO;
-  if (opacity != b.opacity)     d |= SEG_DIFFERS_BRI;
-  if (mode != b.mode)           d |= SEG_DIFFERS_FX;
-  if (speed != b.speed)         d |= SEG_DIFFERS_FX;
-  if (intensity != b.intensity) d |= SEG_DIFFERS_FX;
-  if (palette != b.palette)     d |= SEG_DIFFERS_FX;
-  if (custom1 != b.custom1)     d |= SEG_DIFFERS_FX;
-  if (custom2 != b.custom2)     d |= SEG_DIFFERS_FX;
-  if (custom3 != b.custom3)     d |= SEG_DIFFERS_FX;
-  if (startY != b.startY)       d |= SEG_DIFFERS_BOUNDS;
-  if (stopY != b.stopY)         d |= SEG_DIFFERS_BOUNDS;
-
-  //bit pattern: (msb first)
-  // set:2, sound:2, mapping:3, transposed, mirrorY, reverseY, [reset,] paused, mirrored, on, reverse, [selected]
-  if ((options & 0b1111111111011110U) != (b.options & 0b1111111111011110U)) d |= SEG_DIFFERS_OPT;
-  if ((options & 0x0001U) != (b.options & 0x0001U))                         d |= SEG_DIFFERS_SEL;
-  for (unsigned i = 0; i < NUM_COLORS; i++) if (colors[i] != b.colors[i])   d |= SEG_DIFFERS_COL;
-
-  return d;
-}
-
 void Segment::refreshLightCapabilities() {
   unsigned capabilities = 0;
   unsigned segStartIdx = 0xFFFFU;
@@ -1786,11 +1759,14 @@ Segment& WS2812FX::getSegment(unsigned id) {
 void WS2812FX::resetSegments() {
   _segments.clear(); // destructs all Segment as part of clearing
   #ifndef WLED_DISABLE_2D
-  segment seg = isMatrix ? Segment(0, Segment::maxWidth, 0, Segment::maxHeight) : Segment(0, _length);
+  if (isMatrix) {
+    _segments.emplace_back(0, Segment::maxWidth, 0, Segment::maxHeight);
+  } else {
+    _segments.emplace_back(0, _length);
+  }
   #else
-  segment seg = Segment(0, _length);
+  _segments.emplace_back(0, _length);
   #endif
-  _segments.push_back(seg);
   _segments.shrink_to_fit(); // just in case ...
   _mainSegment = 0;
 }
@@ -1838,12 +1814,12 @@ void WS2812FX::makeAutoSegments(bool forceReset) {
     // there is always at least one segment (but we need to differentiate between 1D and 2D)
     #ifndef WLED_DISABLE_2D
     if (isMatrix)
-      _segments.push_back(Segment(0, Segment::maxWidth, 0, Segment::maxHeight));
+      _segments.emplace_back(0, Segment::maxWidth, 0, Segment::maxHeight);
     else
     #endif
-      _segments.push_back(Segment(segStarts[0], segStops[0]));
+      _segments.emplace_back(segStarts[0], segStops[0]);
     for (size_t i = 1; i < s; i++) {
-      _segments.push_back(Segment(segStarts[i], segStops[i]));
+      _segments.emplace_back(segStarts[i], segStops[i]);
     }
     DEBUG_PRINTF_P(PSTR("%d auto segments created.\n"), _segments.size());
 

wled00/json.cpp

@@ -15,6 +15,34 @@
  * JSON API (De)serialization
  */
 
+namespace {
+bool differs(const Segment& segment, const std::array<byte, sizeof(Segment)>& backup) {
+  const Segment& segmentBackup = *reinterpret_cast<const Segment*>(backup.data());
+  if (segment.start != segmentBackup.start)         return true;
+  if (segment.stop != segmentBackup.stop)           return true;
+  if (segment.offset != segmentBackup.offset)       return true;
+  if (segment.grouping != segmentBackup.grouping)   return true;
+  if (segment.spacing != segmentBackup.spacing)     return true;
+  if (segment.opacity != segmentBackup.opacity)     return true;
+  if (segment.mode != segmentBackup.mode)           return true;
+  if (segment.speed != segmentBackup.speed)         return true;
+  if (segment.intensity != segmentBackup.intensity) return true;
+  if (segment.palette != segmentBackup.palette)     return true;
+  if (segment.custom1 != segmentBackup.custom1)     return true;
+  if (segment.custom2 != segmentBackup.custom2)     return true;
+  if (segment.custom3 != segmentBackup.custom3)     return true;
+  if (segment.startY != segmentBackup.startY)       return true;
+  if (segment.stopY != segmentBackup.stopY)         return true;
+
+  //bit pattern: (msb first)
+  // set:2, sound:2, mapping:3, transposed, mirrorY, reverseY, [reset,] paused, mirrored, on, reverse, [selected]
+  if ((segment.options & 0b1111111111011110U) != (segmentBackup.options & 0b1111111111011110U)) return true;
+  for (unsigned i = 0; i < NUM_COLORS; i++) if (segment.colors[i] != segmentBackup.colors[i])   return true;
+
+  return false;
+}
+}
+
 bool deserializeSegment(JsonObject elem, byte it, byte presetId)
 {
   byte id = elem["id"] | it;
@@ -26,15 +54,16 @@ bool deserializeSegment(JsonObject elem, byte it, byte presetId)
   // append segment
   if (id >= strip.getSegmentsNum()) {
     if (stop <= 0) return false; // ignore empty/inactive segments
-    strip.appendSegment(Segment(0, strip.getLengthTotal()));
+    strip.emplaceSegment(0, strip.getLengthTotal());
     id = strip.getSegmentsNum()-1; // segments are added at the end of list
     newSeg = true;
   }
 
   //DEBUG_PRINTLN(F("-- JSON deserialize segment."));
   Segment& seg = strip.getSegment(id);
   //DEBUG_PRINTF_P(PSTR("--  Original segment: %p (%p)\n"), &seg, seg.data);
-  const Segment prev = seg; //make a backup so we can tell if something changed (calling copy constructor)
+  alignas(Segment) std::array<byte, sizeof(Segment)> segmentBackup; //make a backup so we can tell if something changed (voiding copy constructor)
+  memcpy(segmentBackup.data(), &seg, sizeof(Segment));
   //DEBUG_PRINTF_P(PSTR("--  Duplicate segment: %p (%p)\n"), &prev, prev.data);
 
   int start = elem["start"] | seg.start;
@@ -293,7 +322,7 @@ bool deserializeSegment(JsonObject elem, byte it, byte presetId)
     strip.trigger(); // force segment update
   }
   // send UDP/WS if segment options changed (except selection; will also deselect current preset)
-  if (seg.differs(prev) & 0x7F) stateChanged = true;
+  stateChanged = stateChanged || differs(seg, segmentBackup);
 
   return true;
 }

wled00/led.cpp

@@ -25,24 +25,18 @@ void setValuesFromSegment(uint8_t s)
 
 
 // applies global legacy values (col, colSec, effectCurrent...)
-// problem: if the first selected segment already has the value to be set, other selected segments are not updated
-void applyValuesToSelectedSegs()
-{
-  // copy of first selected segment to tell if value was updated
-  unsigned firstSel = strip.getFirstSelectedSegId();
-  Segment selsegPrev = strip.getSegment(firstSel);
-  for (unsigned i = 0; i < strip.getSegmentsNum(); i++) {
-    Segment& seg = strip.getSegment(i);
-    if (i != firstSel && (!seg.isActive() || !seg.isSelected())) continue;
-
-    if (effectSpeed     != selsegPrev.speed)     {seg.speed     = effectSpeed;     stateChanged = true;}
-    if (effectIntensity != selsegPrev.intensity) {seg.intensity = effectIntensity; stateChanged = true;}
-    if (effectPalette   != selsegPrev.palette)   {seg.setPalette(effectPalette);}
-    if (effectCurrent   != selsegPrev.mode)      {seg.setMode(effectCurrent);}
-    uint32_t col0 = RGBW32(   col[0],    col[1],    col[2],    col[3]);
-    uint32_t col1 = RGBW32(colSec[0], colSec[1], colSec[2], colSec[3]);
-    if (col0 != selsegPrev.colors[0])            {seg.setColor(0, col0);}
-    if (col1 != selsegPrev.colors[1])            {seg.setColor(1, col1);}
+void applyValuesToSelectedSegs() {
+  const uint32_t col0 = RGBW32(   col[0],    col[1],    col[2],    col[3]);
+  const uint32_t col1 = RGBW32(colSec[0], colSec[1], colSec[2], colSec[3]);
+  for (Segment& seg : strip._segments) {
+    if (!(seg.isActive() && seg.isSelected())) continue;
+    stateChanged  = stateChanged || (effectSpeed != seg.speed) || (effectIntensity != seg.intensity);
+    seg.speed     = effectSpeed;
+    seg.intensity = effectIntensity;
+    seg.setPalette(effectPalette);
+    seg.setMode(effectCurrent);
+    seg.setColor(0, col0);
+    seg.setColor(1, col1);
   }
 }
 

wled00/udp.cpp

@@ -272,7 +272,7 @@ static void parseNotifyPacket(const uint8_t *udpIn) {
       DEBUG_PRINTF_P(PSTR("UDP segment received: %u\n"), id);
       if      (id >  strip.getSegmentsNum()) break;
       else if (id == strip.getSegmentsNum()) {
-        if (receiveSegmentBounds && id < strip.getMaxSegments()) strip.appendSegment();
+        if (receiveSegmentBounds && id < strip.getMaxSegments()) strip.emplaceSegment();
         else break;
       }
       DEBUG_PRINTF_P(PSTR("UDP segment check: %u\n"), id);