diff --git a/wled00/FX.h b/wled00/FX.h
index 60b1473c..882f4c9e 100644
--- a/wled00/FX.h
+++ b/wled00/FX.h
@@ -504,6 +504,7 @@ typedef struct Segment {
     static uint16_t getUsedSegmentData(void)    { return _usedSegmentData; }
     static void     addUsedSegmentData(int len) { _usedSegmentData += len; }
 
+    void    set(uint16_t i1, uint16_t i2, uint8_t grp=1, uint8_t spc=0, uint16_t ofs=UINT16_MAX, uint16_t i1Y=0, uint16_t i2Y=1);
     bool    setColor(uint8_t slot, uint32_t c); //returns true if changed
     void    setCCT(uint16_t k);
     void    setOpacity(uint8_t o);
diff --git a/wled00/FX_2Dfcn.cpp b/wled00/FX_2Dfcn.cpp
index 42d2dde0..0ac09998 100644
--- a/wled00/FX_2Dfcn.cpp
+++ b/wled00/FX_2Dfcn.cpp
@@ -43,21 +43,22 @@ void WS2812FX::setUpMatrix() {
 
   // isMatrix is set in cfg.cpp or set.cpp
   if (isMatrix) {
-    Segment::maxWidth  = hPanels * panelW;
-    Segment::maxHeight = vPanels * panelH;
+    uint16_t maxWidth  = hPanels * panelW;
+    uint16_t maxHeight = vPanels * panelH;
 
     // safety check
-    if (Segment::maxWidth * Segment::maxHeight > MAX_LEDS || Segment::maxWidth == 1 || Segment::maxHeight == 1) {
-      Segment::maxWidth = _length;
-      Segment::maxHeight = 1;
+    if (maxWidth * maxHeight > MAX_LEDS || maxWidth == 1 || maxHeight == 1) {
       isMatrix = false;
       return;
     }
 
-    customMappingSize  = Segment::maxWidth * Segment::maxHeight;
-    customMappingTable = new uint16_t[customMappingSize];
+    customMappingTable = new uint16_t[maxWidth * maxHeight];
 
     if (customMappingTable != nullptr) {
+      Segment::maxWidth  = maxWidth;
+      Segment::maxHeight = maxHeight;
+      customMappingSize  = maxWidth * maxHeight;
+
       uint16_t startL; // index in custom mapping array (logical strip)
       uint16_t startP; // position of 1st pixel of panel on (virtual) strip
       uint16_t x, y, offset;
@@ -94,18 +95,12 @@ void WS2812FX::setUpMatrix() {
       }
       DEBUG_PRINTLN();
       #endif
-    } else {
-      // memory allocation error
-      Segment::maxWidth = _length;
-      Segment::maxHeight = 1;
+    } else { // memory allocation error
       isMatrix = false;
-      return;
     }
-  } else { 
-    // not a matrix set up
-    Segment::maxWidth = _length;
-    Segment::maxHeight = 1;
   }
+#else
+  isMatrix = false; // no matter what config says
 #endif
 }
 
diff --git a/wled00/FX_fcn.cpp b/wled00/FX_fcn.cpp
index cc3b122e..d2a8182e 100644
--- a/wled00/FX_fcn.cpp
+++ b/wled00/FX_fcn.cpp
@@ -376,6 +376,45 @@ void Segment::handleTransition() {
   }
 }
 
+void Segment::set(uint16_t i1, uint16_t i2, uint8_t grp, uint8_t spc, uint16_t ofs, uint16_t i1Y, uint16_t i2Y) {
+  //return if neither bounds nor grouping have changed
+  bool boundsUnchanged = (start == i1 && stop == i2);
+  if (Segment::maxHeight>1) { //2D
+    boundsUnchanged &= (startY == i1Y && stopY == i2Y);
+  }
+  if (boundsUnchanged
+      && (!grp || (grouping == grp && spacing == spc))
+      && (ofs == UINT16_MAX || ofs == offset)) return;
+
+  if (stop) fill(BLACK); //turn old segment range off
+  if (i2 <= i1) { //disable segment
+    stop = 0;
+    markForReset();
+    return;
+  }
+  if (Segment::maxHeight>1) { // 2D
+    #ifndef WLED_DISABLE_2D
+    if (i1 < Segment::maxWidth) start = i1;
+    stop = i2 > Segment::maxWidth ? Segment::maxWidth : i2;
+    if (i1Y < Segment::maxHeight) startY = i1Y;
+    stopY = i2Y > Segment::maxHeight ? Segment::maxHeight : MAX(1,i2Y);
+    #endif
+  } else {
+    if (i1 < strip.getLengthTotal()) start = i1;
+    stop = i2 > strip.getLengthTotal() ? strip.getLengthTotal() : i2;
+    startY = 0;
+    stopY  = 1;
+  }
+  if (grp) {
+    grouping = grp;
+    spacing = spc;
+  }
+  if (ofs < UINT16_MAX) offset = ofs;
+  markForReset();
+  if (!boundsUnchanged) refreshLightCapabilities();
+}
+
+
 bool Segment::setColor(uint8_t slot, uint32_t c) { //returns true if changed
   if (slot >= NUM_COLORS || c == colors[slot]) return false;
   if (fadeTransition) startTransition(strip.getTransition()); // start transition prior to change
@@ -957,6 +996,11 @@ void WS2812FX::finalizeInit(void)
     #endif
   }
 
+  if (!isMatrix) { // if 2D then max values defined in setUpMatrix() using panel set-up
+    Segment::maxWidth  = _length;
+    Segment::maxHeight = 1;
+   }
+
   //initialize leds array. TBD: realloc if nr of leds change
   if (Segment::_globalLeds) {
     purgeSegments(true);
@@ -1319,54 +1363,7 @@ Segment& WS2812FX::getSegment(uint8_t id) {
 
 void WS2812FX::setSegment(uint8_t n, uint16_t i1, uint16_t i2, uint8_t grouping, uint8_t spacing, uint16_t offset, uint16_t startY, uint16_t stopY) {
   if (n >= _segments.size()) return;
-  Segment& seg = _segments[n];
-
-  //return if neither bounds nor grouping have changed
-  bool boundsUnchanged = (seg.start == i1 && seg.stop == i2);
-  if (isMatrix) {
-    boundsUnchanged &= (seg.startY == startY && seg.stopY == stopY);
-  }
-  if (boundsUnchanged
-      && (!grouping || (seg.grouping == grouping && seg.spacing == spacing))
-      && (offset == UINT16_MAX || offset == seg.offset)) return;
-
-  //if (seg.stop) setRange(seg.start, seg.stop -1, BLACK); //turn old segment range off
-  if (seg.stop) seg.fill(BLACK); //turn old segment range off
-  if (i2 <= i1) //disable segment
-  {
-    // disabled segments should get removed using purgeSegments()
-    DEBUG_PRINT(F("-- Segment ")); DEBUG_PRINT(n); DEBUG_PRINTLN(F(" marked inactive."));
-    seg.stop = 0;
-    seg.options = 0b0000000000000101; // on & selected
-    //if (seg.name) {
-    //  delete[] seg.name;
-    //  seg.name = nullptr;
-    //}
-    // if main segment is deleted, set first active as main segment
-    if (n == _mainSegment) setMainSegmentId(0);
-    seg.markForReset();
-    return;
-  }
-  if (isMatrix) {
-    #ifndef WLED_DISABLE_2D
-    if (i1 < Segment::maxWidth) seg.start = i1;
-    seg.stop = i2 > Segment::maxWidth ? Segment::maxWidth : i2;
-    if (startY < Segment::maxHeight) seg.startY = startY;
-    seg.stopY = stopY > Segment::maxHeight ? Segment::maxHeight : MAX(1,stopY);
-    #endif
-  } else {
-    if (i1 < _length) seg.start = i1;
-    seg.stop = i2 > _length ? _length : i2;
-    seg.startY = 0;
-    seg.stopY  = 1;
-  }
-  if (grouping) {
-    seg.grouping = grouping;
-    seg.spacing = spacing;
-  }
-  if (offset < UINT16_MAX) seg.offset = offset;
-  seg.markForReset();
-  if (!boundsUnchanged) seg.refreshLightCapabilities();
+  _segments[n].set(i1, i2, grouping, spacing, offset, startY, stopY);
 }
 
 void WS2812FX::restartRuntime() {
diff --git a/wled00/json.cpp b/wled00/json.cpp
index 192afd4b..fe87e4f6 100644
--- a/wled00/json.cpp
+++ b/wled00/json.cpp
@@ -105,7 +105,7 @@ void deserializeSegment(JsonObject elem, byte it, byte presetId)
     of = offsetAbs;
   }
   if (stop > start && of > len -1) of = len -1;
-  strip.setSegment(id, start, stop, grp, spc, of, startY, stopY);
+  seg.set(start, stop, grp, spc, of, startY, stopY);
 
   byte segbri = seg.opacity;
   if (getVal(elem["bri"], &segbri)) {
diff --git a/wled00/set.cpp b/wled00/set.cpp
index 0369e2e3..cb66937d 100644
--- a/wled00/set.cpp
+++ b/wled00/set.cpp
@@ -744,7 +744,7 @@ bool handleSet(AsyncWebServerRequest *request, const String& req, bool apply)
   if (pos > 0) {
     spcI = getNumVal(&req, pos);
   }
-  strip.setSegment(selectedSeg, startI, stopI, grpI, spcI, UINT16_MAX, startY, stopY);
+  selseg.set(startI, stopI, grpI, spcI, UINT16_MAX, startY, stopY);
 
   pos = req.indexOf(F("RV=")); //Segment reverse
   if (pos > 0) selseg.reverse = req.charAt(pos+3) != '0';
diff --git a/wled00/udp.cpp b/wled00/udp.cpp
index 2d1388f8..06172f6e 100644
--- a/wled00/udp.cpp
+++ b/wled00/udp.cpp
@@ -363,7 +363,7 @@ void handleNotifications()
           uint16_t stopY  = 1, stop   = (udpIn[3+ofs] << 8 | udpIn[4+ofs]);
           uint16_t offset = (udpIn[7+ofs] << 8 | udpIn[8+ofs]);
           if (!receiveSegmentOptions) {
-            strip.setSegment(id, start, stop, selseg.grouping, selseg.spacing, offset, startY, stopY);
+            selseg.set(start, stop, selseg.grouping, selseg.spacing, offset, startY, stopY);
             continue;
           }
           //for (size_t j = 1; j<4; j++) selseg.setOption(j, (udpIn[9 +ofs] >> j) & 0x01); //only take into account mirrored, on, reversed; ignore selected
@@ -396,11 +396,10 @@ void handleNotifications()
             startY = (udpIn[32+ofs] << 8 | udpIn[33+ofs]);
             stopY  = (udpIn[34+ofs] << 8 | udpIn[35+ofs]);
           }
-          //setSegment() also properly resets segments
           if (receiveSegmentBounds) {
-            strip.setSegment(id, start, stop, udpIn[5+ofs], udpIn[6+ofs], offset, startY, stopY);
+            selseg.set(start, stop, udpIn[5+ofs], udpIn[6+ofs], offset, startY, stopY);
           } else {
-            strip.setSegment(id, selseg.start, selseg.stop, udpIn[5+ofs], udpIn[6+ofs], selseg.offset, selseg.startY, selseg.stopY);
+            selseg.set(selseg.start, selseg.stop, udpIn[5+ofs], udpIn[6+ofs], selseg.offset, selseg.startY, selseg.stopY);
           }
         }
         stateChanged = true;