From 5df45136f74c34f4cd93fda9a8b427e3866a09e6 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 18 Apr 2026 15:45:48 +0000
Subject: [PATCH] freqdisplay: auto-fit font to available width and height so
 text is always fully visible

Agent-Logs-Url: https://github.com/srcejon/sdrangel/sessions/a5adfa9d-7047-46b6-8d9f-ded5f125ab8c

Co-authored-by: srcejon <57259258+srcejon@users.noreply.github.com>
---
 .../feature/freqdisplay/freqdisplaygui.cpp    | 29 +++++++++++++++----
 1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/plugins/feature/freqdisplay/freqdisplaygui.cpp b/plugins/feature/freqdisplay/freqdisplaygui.cpp
index 5bba06e0d..fa20e4c02 100644
--- a/plugins/feature/freqdisplay/freqdisplaygui.cpp
+++ b/plugins/feature/freqdisplay/freqdisplaygui.cpp
@@ -11,9 +11,6 @@
 #include "freqdisplaygui.h"
 
 namespace {
-// For typical feature windows this keeps the text close to ~22% of the smallest
-// widget dimension, which yields large readable digits without clipping.
-constexpr double frequencyFontScale = 0.22;
 constexpr const char* rxTxChannelKinds = "RT";
 constexpr int pollIntervalMs = 1000;
 constexpr int minimumFrequencyFontPointSize = 10;
@@ -239,13 +236,33 @@ void FreqDisplayGUI::updateFrequencyText()
 
 void FreqDisplayGUI::updateFrequencyFont()
 {
-    const int minDimension = qMin(ui->frequencyValue->width(), ui->frequencyValue->height());
-    if (minDimension <= 0) {
+    const int availableWidth = ui->frequencyValue->width();
+    const int availableHeight = ui->frequencyValue->height();
+    if (availableWidth <= 0 || availableHeight <= 0) {
         return;
     }
-    const int pointSize = qMax(minimumFrequencyFontPointSize, static_cast<int>(minDimension * frequencyFontScale));
 
+    const QString text = ui->frequencyValue->text();
+    if (text.isEmpty()) {
+        return;
+    }
+
+    // Probe at a large reference size to get accurate text dimensions, then
+    // scale linearly to find the largest point size that fits in both directions.
     QFont font = ui->frequencyValue->font();
+    constexpr int probeSize = 200;
+    font.setPointSize(probeSize);
+    const QFontMetrics fm(font);
+    const int textWidth = fm.horizontalAdvance(text);
+    const int textHeight = fm.height();
+
+    if (textWidth <= 0 || textHeight <= 0) {
+        return;
+    }
+
+    const int maxFromWidth  = probeSize * availableWidth  / textWidth;
+    const int maxFromHeight = probeSize * availableHeight / textHeight;
+    const int pointSize = qMax(minimumFrequencyFontPointSize, qMin(maxFromWidth, maxFromHeight));
     font.setPointSize(pointSize);
     ui->frequencyValue->setFont(font);
 }