From 1918645d5387c36c3d6648013747f3a2fd0aead6 Mon Sep 17 00:00:00 2001
From: ericek111 <erik.brocko@letemsvetemapplem.eu>
Date: Wed, 25 Mar 2026 21:53:36 +0100
Subject: [PATCH] Cursors: optional snapping

---
 src/ui/Application.cpp | 20 ++++++++++----------
 src/ui/Cursors.cpp     |  6 ++++--
 src/ui/Cursors.h       |  1 +
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/ui/Application.cpp b/src/ui/Application.cpp
index c8a4f52..52fb892 100644
--- a/src/ui/Application.cpp
+++ b/src/ui/Application.cpp
@@ -1112,17 +1112,17 @@ void Application::handleSpectrumInput(float posX, float posY,
             cursors_.hover = {true, freq, dB, bin};
         }
 
-        // Left click: cursor A
-        if (ImGui::IsMouseClicked(ImGuiMouseButton_Left)) {
-            int peakBin = cursors_.findLocalPeak(spec, bin, 10);
-            double peakFreq = analyzer_.binToFreq(peakBin);
-            cursors_.setCursorA(peakFreq, spec[peakBin], peakBin);
+        // Left drag: cursor A
+        if (ImGui::IsMouseDown(ImGuiMouseButton_Left)) {
+            int cBin = cursors_.snapToPeaks ? cursors_.findLocalPeak(spec, bin, 10) : bin;
+            double cFreq = analyzer_.binToFreq(cBin);
+            cursors_.setCursorA(cFreq, spec[cBin], cBin);
         }
-        // Right click: cursor B
-        if (ImGui::IsMouseClicked(ImGuiMouseButton_Right)) {
-            int peakBin = cursors_.findLocalPeak(spec, bin, 10);
-            double peakFreq = analyzer_.binToFreq(peakBin);
-            cursors_.setCursorB(peakFreq, spec[peakBin], peakBin);
+        // Right drag: cursor B
+        if (ImGui::IsMouseDown(ImGuiMouseButton_Right)) {
+            int cBin = cursors_.snapToPeaks ? cursors_.findLocalPeak(spec, bin, 10) : bin;
+            double cFreq = analyzer_.binToFreq(cBin);
+            cursors_.setCursorB(cFreq, spec[cBin], cBin);
         }
 
         {
diff --git a/src/ui/Cursors.cpp b/src/ui/Cursors.cpp
index 8aa0a91..a6d1787 100644
--- a/src/ui/Cursors.cpp
+++ b/src/ui/Cursors.cpp
@@ -83,7 +83,7 @@ void Cursors::draw(const SpectrumDisplay& specDisplay,
 
     float aDB = avgDBA(), bDB = avgDBB();
     drawCursorMarker(cursorA, aDB, IM_COL32(255, 255, 0, 220));
-    drawCursorMarker(cursorB, bDB, IM_COL32(0, 200, 255, 220));
+    drawCursorMarker(cursorB, bDB, IM_COL32(100, 220, 255, 220));
 
     // Draw labels at the top, touching the cursor's vertical line.
     // If the label would overflow the right edge, flip it to the left side.
@@ -113,7 +113,7 @@ void Cursors::draw(const SpectrumDisplay& specDisplay,
     };
 
     drawCursorLabel(cursorA, aDB, IM_COL32(255, 255, 0, 220), "A", 0);
-    drawCursorLabel(cursorB, bDB, IM_COL32(0, 200, 255, 220), "B", cursorA.active ? 1 : 0);
+    drawCursorLabel(cursorB, bDB, IM_COL32(100, 220, 255, 220), "B", cursorA.active ? 1 : 0);
 
     // Delta display (two lines, column-aligned on '=')
     if (showDelta && cursorA.active && cursorB.active) {
@@ -156,6 +156,8 @@ void Cursors::drawPanel() {
         ImGui::Text("%s", dbuf);
     }
 
+    ImGui::Checkbox("Snap to peaks", &snapToPeaks);
+
     // Averaging slider (logarithmic scale)
     ImGui::SetNextItemWidth(-1);
     ImGui::SliderInt("##avgcount", &avgCount, 1, 20000, avgCount == 1 ? "No avg" : "Avg: %d",
diff --git a/src/ui/Cursors.h b/src/ui/Cursors.h
index f3cd695..eb0f473 100644
--- a/src/ui/Cursors.h
+++ b/src/ui/Cursors.h
@@ -45,6 +45,7 @@ public:
     CursorInfo cursorA;
     CursorInfo cursorB;
     bool       showDelta = true;
+    bool       snapToPeaks = true;
 
     // Hover cursor (follows mouse, always active)
     CursorInfo hover;