fix(editor): close curve popup on zone-count change; degenerate-rect guard + comment corrections

src/vst/reasampler_editor.cpp

@@ -164,6 +164,7 @@ void ReaSamplerEditor::refreshFromBank() {
     samples_ = banksJson ? listSamples(*banksJson) : std::vector<SampleChoice>{};
     banks_ = banksJson ? listBanks(*banksJson) : std::vector<BankChoice>{};
     selectedId_ = processor_->selectedSampleId();
+    const auto prevZoneCount = static_cast<int>(map_.zones.size());
     map_ = processor_->performanceMap();
     channelMode_ = processor_->channelMode();
     voiceCount_ = processor_->voiceCount();      // Phase S voice-deck snapshot
@@ -174,9 +175,13 @@ void ReaSamplerEditor::refreshFromBank() {
     // curve popup — the empty-state Sample face no longer draws it, and an open-but-invisible
     // modal would swallow clicks.
     if (selectedId_.empty() && map_.zones.empty()) curvePopupOpen_ = false;
-    // FB2: on the Zone surface the popup edits the SELECTED zone; if the refresh dropped the
+    // FB2: on the Zone surface the popup edits the SELECTED zone; close it if the zones list
-    // selection (the zones list shrank), close it rather than let it retarget another zone.
+    // shrank (selectedZone_ past-end), OR if the zone count changed at all — a mid-list
-    if (view_ == View::kZone && selectedZone_ < 0) curvePopupOpen_ = false;
+    // deletion leaves selectedZone_ in range but now naming a DIFFERENT zone (silent retarget).
+    if (view_ == View::kZone && curvePopupOpen_) {
+        const auto newZoneCount = static_cast<int>(map_.zones.size());
+        if (selectedZone_ < 0 || newZoneCount != prevZoneCount) curvePopupOpen_ = false;
+    }
     // Drop a filter that names a bank no longer present.
     if (!activeFilterBankId_.empty()) {
         bool found = false;
@@ -877,7 +882,7 @@ constexpr int kPad = 8;
 // cluster's and the Zone panel's (the inline Zone box is retired). The INSET keeps node handles
 // + the pick radius inside the border so an endpoint at amp 0/1 stays grabbable — the ONE
 // curveBoxFromRect grammar the popup derives its mapping box through.
-constexpr int kVelCurveInset = 14;    // border -> mapping-box inset: caption band (~12px) + 2px gap
+constexpr int kVelCurveInset = 14;    // border -> mapping-box inset: keeps endpoint handles + pick radius inside the border
 constexpr int kCurveDragOffMargin = 24;  // release beyond box+margin -> drag-off delete
 
 // The r11 cluster's fixed right-anchored run (left -> right: Preview button, the radial
@@ -996,9 +1001,10 @@ Rect zonesControlPanel(const Rect& content) {
 // FB2 (R11-F2 parity): the Zone panel's per-zone controls render as the SAME knob deck the
 // Sample face uses. The deck lays out from the panel top (top-anchored — the Zone panel reads
 // top-down, unlike the Sample face's bottom-anchored band), with a column at the panel's right
-// reserved for the mini curve-preview button so a deck row can never collide with it (the pure
+// reserved for the mini curve-preview button so no deck row starts inside it (layoutDeck places
-// knob_deck wrap keeps whole groups inside availWidth). Both draw + hit-test derive from these
+// the first group of each row unconditionally; collision avoidance relies on the available
-// two formulas so they never drift.
+// width margin in practice). Both draw + hit-test derive from these two formulas so they never
+// drift.
 Rect zonesDeckArea(const Rect& content) {
     const Rect panel = zonesControlPanel(content);
     return Rect{panel.left, panel.top, panel.right - kCurveBtnSize - kPad, panel.bottom};
@@ -1544,6 +1550,7 @@ void ReaSamplerEditor::paintKnobDeck(LICE_IBitmap* bmp, const Rect& deckArea,
 
 void ReaSamplerEditor::paintCurveButton(LICE_IBitmap* bmp, const Rect& r,
                                         const PerformanceZone& zone) {
+    if (r.width() <= 0 || r.height() <= 0) return;
     // The mini curve-preview button (r11/FB2 — shared by the Sample cluster and the Zone
     // panel): a hairline-bordered bg/cell square with the zone's live velocity curve traced
     // in miniature (no node markers at this scale). Hover lifts it; it draws ACTIVE

src/vst/reasampler_editor.h

@@ -143,7 +143,7 @@ private:
         kPreview,         // the Sample-view preview-trigger button
         kAddZone,         // the "+ Add Zone" button
         kDeleteZone,      // the "Delete" zone button
-        kControl,         // a param-panel control row / deck element (index = control id)
+        kControl,         // a knob-deck element (index = control id)
         kCurveNode,       // a velocity-curve control point (index = point index, S-VIEW-10)
         kVelKnob,         // the cluster preview-velocity radial knob (r11)
         kCurveButton,     // the cluster mini curve-preview button (r11 — opens the popup)