Rebuild the chrome band: full-width piano strip with uniform key widths, note tooltips, one toolbar font

src/shell/instrument/editor_input_chrome.cpp

@@ -1,12 +1,12 @@
 // editor_input_chrome.cpp — the CHROME band's input: the Browse nav, the preview trigger,
 // the preview-velocity knob grab, the curve-button summon, the channel toggle, and the
-// root-marker grab plus its live drag. Windows-only.
+// piano strip's root grab plus its live drag. Windows-only.
 
 #include "shell/instrument/reasampler_editor.h"
 
 #ifdef _WIN32
 
-#include "core/instrument/ui/keyboard_strip.h"  // keyAtPoint / resolveDragNote (root marker)
+#include "core/instrument/ui/keyboard_strip.h"  // keyAtPoint / resolveDragNote (root key)
 #include "shell/instrument/editor_internal.h"
 #include "shell/instrument/reasampler_processor.h"
 
@@ -69,31 +69,32 @@ bool ReaSamplerEditor::mouseDownChrome(const FaceLayout& fl, int x, int y) {
         return true;
     }
 
-    // The root strip: grab the root marker. A plain click sets the root to the clicked key
-    // (applied below as the first delta==0 move).
-    if (cr.rootStrip.width > 0) {
+    // The piano strip: clicking a key sets the root, and holding tracks the pointer. The
+    // click itself lands below as the first (unmoved) drag resolve.
+    if (!cr.rootStrip.empty()) {
         const StripLayout sl = layoutStrip(cr.rootStrip.width, cr.rootStrip.height);
-        const int note = keyAtPoint(sl, x - cr.rootStrip.x, y - cr.rootStrip.y);
-        if (note >= 0) {
+        if (keyAtPoint(sl, x - cr.rootStrip.x, y - cr.rootStrip.y) >= 0) {
             drag_ = DragKind::kRootMarker;
             dragStartX_ = x;
-            dragStartRoot_ = note;
             dragStartParams_ = params_;
-            onMouseMove(x, y);  // apply the click as the first delta==0 set
+            onMouseMove(x, y);
             return true;
         }
     }
-    // A click on the control row's background is consumed so it can't fall through to a
+    // A click on the strip row's background is consumed so it can't fall through to a
     // band the user cannot see under the chrome.
     return contains(cr.controls, x, y);
 }
 
 void ReaSamplerEditor::dragChrome(const FaceLayout& fl, int x, int y) {
-    (void)y;
     const Rect& stripArea = fl.chrome.rootStrip;
-    if (stripArea.width <= 0) return;
+    if (stripArea.empty()) return;
+    // Absolute tracking, not a pixel delta: with black keys overlaying whites there is no
+    // one pixels-per-semitone rate a delta could use.
     const StripLayout sl = layoutStrip(stripArea.width, stripArea.height);
-    params_.rootOverride = resolveDragNote(sl, dragStartRoot_, x - dragStartX_);
+    const int note = resolveDragNote(sl, x - stripArea.x, y - stripArea.y);
+    if (note < 0) return;
+    params_.rootOverride = note;
     invalidate();  // live feedback; the commit lands on WM_LBUTTONUP
 }
 
@@ -107,6 +108,11 @@ ReaSamplerEditor::HoverTarget ReaSamplerEditor::hoverChrome(const FaceLayout& fl
     if (contains(cr.curveBtn, x, y)) return {HoverKind::kCurveButton, -1};
     if (contains(cr.chanMono, x, y)) return {HoverKind::kChanMono, -1};
     if (contains(cr.chanStereo, x, y)) return {HoverKind::kChanStereo, -1};
+    if (!cr.rootStrip.empty()) {
+        const StripLayout sl = layoutStrip(cr.rootStrip.width, cr.rootStrip.height);
+        const int note = keyAtPoint(sl, x - cr.rootStrip.x, y - cr.rootStrip.y);
+        if (note >= 0) return {HoverKind::kStripKey, note};
+    }
     return {};
 }