Keysigs on section break

src/engraving/dom/edit.cpp

@@ -6151,6 +6151,19 @@ void Score::undoAddElement(EngravingItem* element, bool addToLinkedStaves, bool
         if (lb->layoutBreakType() == LayoutBreakType::SECTION) {
             doUndoAddElement(lb);
             MeasureBase* m = lb->measure();
+
+            // add Key Signature on Section Break
+            Fraction tick = m->endTick();
+            int ticks = tick.ticks();
+            for (Staff* staff : score()->staves()) {
+                KeyList* kl = staff->keyList();
+                KeySigEvent ks = kl->key(ticks);
+                if (kl->currentKeyTick(ticks) != ticks || ks.forInstrumentChange()) {
+                    ks.setForInstrumentChange(false);
+                    ks.setForSectionBreak(true);
+                    undoChangeKeySig(staff, tick, ks);
+                }
+            }
             if (m->isBox()) {
                 // for frames, use linked frames
                 LinkedObjects* links = m->links();
@@ -6973,6 +6986,44 @@ void Score::undoRemoveElement(EngravingItem* element, bool removeLinked)
         }
     }
 
+    // remove section break key signatures
+    if (element->isLayoutBreak() && toLayoutBreak(element)->isSectionBreak()) {
+        MeasureBase* mb = element->findMeasureBase();
+        Measure* nextMeasure = mb ? mb->nextMeasure() : nullptr;
+        if (nextMeasure && nextMeasure->isMMRest()) {
+            nextMeasure = nextMeasure->mmRestFirst();
+        }
+        Segment* keySeg = nextMeasure ? nextMeasure->findFirstR(SegmentType::KeySig, Fraction(0, 1)) : nullptr;
+        if (keySeg) {
+            for (staff_idx_t i = 0; i <= nstaves(); i++) {
+                KeySig* ks = toKeySig(keySeg->element(i * VOICES));
+                if (ks && ks->forSectionBreak()) {
+                    Staff* staff = ks->staff();
+                    Fraction tick = ks->tick();
+                    KeySigEvent actualKey = ks->keySigEvent();
+                    KeySigEvent prevKey = staff->prevKey(tick);
+
+                    // do not remove keysig on first measure, or if signatures differ
+                    bool isFirst = ks->tick().isZero(); // this should never happen, but to be sure
+
+                    // if previous signature is "forInstrumentChange",
+                    // comparation returns false, even if they are otherwise identical
+                    // (because one is forInstrumentChange and second not)
+                    // so we need to remove "forInstrumentChange" flag first
+                    if (prevKey.forInstrumentChange()) {
+                        prevKey.setForInstrumentChange(false);
+                    }
+
+                    if (isFirst || actualKey != prevKey) {
+                        ks->setForSectionBreak(false);
+                    } else {
+                        deleteItem(ks);
+                    }
+                }
+            }
+        }
+    }
+
     for (Segment* s : segments) {
         if (s->empty()) {
             if (s->header() || s->trailer()) {        // probably more segment types (system header)

src/engraving/dom/key.h

@@ -82,6 +82,8 @@ class KeySigEvent
     bool isAtonal() const { return m_mode == KeyMode::NONE; }
     void setForInstrumentChange(bool forInstrumentChange) { m_forInstrumentChange = forInstrumentChange; }
     bool forInstrumentChange() const { return m_forInstrumentChange; }
+    void setForSectionBreak(bool forSectionBreak) { m_forSectionBreak = forSectionBreak; }
+    bool forSectionBreak() const { return m_forSectionBreak; }
     void initFromSubtype(int);      // for backward compatibility
     int degInKey(int degree) const; // return "absolute degree"
     SymId symInKey(SymId sym, int degree) const;
@@ -97,6 +99,7 @@ class KeySigEvent
     KeyMode m_mode = KeyMode::UNKNOWN;
     bool m_custom = false;
     bool m_forInstrumentChange = false;
+    bool m_forSectionBreak = false;
     std::vector<CustDef> m_customKeyDefs;
 };
 

src/engraving/dom/keysig.h

@@ -91,6 +91,9 @@ class KeySig final : public EngravingItem
     void setForInstrumentChange(bool forInstrumentChange) { m_sig.setForInstrumentChange(forInstrumentChange); }
     bool forInstrumentChange() const { return m_sig.forInstrumentChange(); }
 
+    void setForSectionBreak(bool forSectionBreak) { m_sig.setForSectionBreak(forSectionBreak); }
+    bool forSectionBreak() const { return m_sig.forSectionBreak(); }
+
     PropertyValue getProperty(Pid propertyId) const override;
     bool setProperty(Pid propertyId, const PropertyValue&) override;
     PropertyValue propertyDefault(Pid id) const override;