UltraLog 3.1.0 — values at the pointer

CLAUDE.md

@@ -672,7 +672,7 @@ preferences convert them.
 
 ### Settings Persistence Contract
 
-`UserSettings` (`src/settings.rs`) is a `Serialize`/`Deserialize` struct persisted as JSON at `{app_data_dir}/UltraLog/settings.json` (or `.../ultralog/settings.json` on Linux). It currently covers: `language`, `scroll_to_zoom`, `show_grid`, `grid_opacity`, `unit_preferences`, `font_scale`, `color_blind_mode`, `ultra_intensity`, `high_contrast`, `field_normalization`, `cursor_tracking`, `auto_check_updates`, `custom_normalizations`, and the Track Map preferences (`tile_provider`, `tile_cache_max_mb`, `tiles_enabled`, `tile_opacity`, `tile_grayscale`, `tile_privacy_notice_seen`, `hidden_widgets`), and `export` (the ExportDialog's last format and theme per format).
+`UserSettings` (`src/settings.rs`) is a `Serialize`/`Deserialize` struct persisted as JSON at `{app_data_dir}/UltraLog/settings.json` (or `.../ultralog/settings.json` on Linux). It currently covers: `language`, `scroll_to_zoom`, `show_grid`, `hover_readout` (default on), `grid_opacity`, `unit_preferences`, `font_scale`, `color_blind_mode`, `ultra_intensity`, `high_contrast`, `field_normalization`, `cursor_tracking`, `auto_check_updates`, `custom_normalizations`, and the Track Map preferences (`tile_provider`, `tile_cache_max_mb`, `tiles_enabled`, `tile_opacity`, `tile_grayscale`, `tile_privacy_notice_seen`, `hidden_widgets`), and `export` (the ExportDialog's last format and theme per format).
 
 - **Load** - `UltraLogApp::new` calls `UserSettings::load()` and copies each field into the corresponding live `UltraLogApp` field (e.g. `app.color_blind_mode = user_settings.color_blind_mode`).
 - **Save** - `UltraLogApp` implements `eframe::App::save`, which eframe calls on its auto-save interval (~30s) and again at shutdown. `save()` rebuilds a `UserSettings` from the current live fields, and only writes to disk if it differs from the last-loaded/saved value.
@@ -877,6 +877,7 @@ ColorScale, and the footer (ultralog.co · version · export date).
 - **Playback** - Play through log data at 0.25x to 8x speed
 - **Cursor Tracking** - Lock view to follow cursor during playback/scrubbing
 - **Min/Max Legend** - Shows peak values for each channel
+- **Hover Readout** - A hairline and a value box at the mouse pointer with every series' value there (issue #98 follow-up), beside the cursor legend; `plot_style::hover_readout`, rows from `series_rows_at`, so log B and R4 apply. It turns off egui_plot's crosshair (`show_crosshair(!hover_readout)`); Settings → Display → Values at the pointer
 - **Initial Zoom** - Charts start zoomed to first 60 seconds for better initial view
 - **Multi-File Tabs** - Chrome-style tabs for working with multiple log files simultaneously
 - **Internationalization** - `rust-i18n`-backed language selection (`src/i18n.rs`)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ultralog"
-version = "3.0.0"
+version = "3.1.0"
 edition = "2024"
 # egui/eframe 0.36 is the binding constraint on the minimum supported Rust
 # version; edition 2024 itself only needs 1.85.

README.md

@@ -6,7 +6,7 @@ A high-performance, cross-platform ECU log viewer written in Rust.
 
 ![CI](https://github.com/ClassicMiniDIY/UltraLog/actions/workflows/ci.yml/badge.svg)
 ![License](https://img.shields.io/badge/license-AGPL--3.0-blue.svg)
-![Version](https://img.shields.io/badge/version-3.0.0-green.svg)
+![Version](https://img.shields.io/badge/version-3.1.0-green.svg)
 
 ---
 
@@ -47,6 +47,7 @@ UltraLog is an **independent, open-source** desktop application designed for aut
 - **Normalized display** - All channels scaled 0-1 for easy comparison regardless of original units
 - **Min/Max legend** - Peak values displayed for each channel at a glance
 - **Real-time cursor values** - Legend shows live values at cursor position with proper units
+- **Values at the pointer** - Move the mouse over the chart for a line and a box with every channel's value at that point, without clicking (turn it off in Settings → Display)
 - **High-performance rendering** - LTTB (Largest Triangle Three Buckets) algorithm reduces millions of points to 2,000 while preserving visual fidelity
 - **Stacked plot areas** - Split the chart into up to 10 independent vertically-stacked panels, each with its own Y-axis and channel set — ideal for comparing channels with wildly different scales
 

i18n/ar.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "عجلة الماوس تكبر المخطط مباشرة بدلاً من الإزاحة"
   show_grid: "إظهار الشبكة"
   show_grid_desc: "رسم شبكة الخلفية للرسم البياني"
+  hover_readout: "القيم عند المؤشر"
+  hover_readout_desc: "اعرض خطاً وقيمة كل قناة حيث تشير الفأرة على الرسم البياني"
   grid_opacity: "الشفافية:"
   field_names: "أسماء الحقول"
   field_normalization: "توحيد الحقول"

i18n/bn.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "মাউস হুইল সরাসরি চার্টকে জুম করে প্যানিং এর পরিবর্তে"
   show_grid: "গ্রিড দেখান"
   show_grid_desc: "চার্ট পটভূমি গ্রিড আঁকুন"
+  hover_readout: "পয়েন্টারে মান"
+  hover_readout_desc: "চার্টে মাউস যেখানে আছে সেখানে একটি রেখা এবং প্রতিটি চ্যানেলের মান দেখান"
   grid_opacity: "স্বচ্ছতা:"
   field_names: "ফিল্ড নাম"
   field_normalization: "ফিল্ড নরমালাইজেশন"

i18n/de.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "Mausrad zoomt direkt in das Diagramm, anstatt es zu verschieben"
   show_grid: "Gitter anzeigen"
   show_grid_desc: "Gitter im Hintergrund anzeichnen"
+  hover_readout: "Werte am Mauszeiger"
+  hover_readout_desc: "Zeigt eine Linie und den Wert jedes Kanals dort, wo die Maus im Diagramm steht"
   grid_opacity: "Deckkraft:"
   field_names: "Feldnamen"
   field_normalization: "Feldnormalisierung"

i18n/en.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "Scroll wheel zooms the chart directly instead of panning"
   show_grid: "Show grid"
   show_grid_desc: "Draw the chart background grid"
+  hover_readout: "Values at the pointer"
+  hover_readout_desc: "Show a line and every channel's value where the mouse points on the chart"
   grid_opacity: "Opacity"
   field_names: "Field Names"
   field_normalization: "Field normalization"

i18n/es.yaml

@@ -70,6 +70,8 @@ settings:
   scroll_to_zoom_desc: "La rueda de desplazamiento amplía el gráfico directamente en lugar de desplazarse"
   show_grid: "Mostrar cuadrícula"
   show_grid_desc: "Mostrar la cuadrícula de fondo del gráfico"
+  hover_readout: "Valores en el puntero"
+  hover_readout_desc: "Muestra una línea y el valor de cada canal donde apunta el ratón en el gráfico"
   grid_opacity: "Opacidad:"
   field_names: "Nombres de Campos"
   field_normalization: "Normalizacion de Campos"

i18n/fr.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "La molette de la souris zoome le graphique directement au lieu de faire defiler"
   show_grid: "Afficher la grille"
   show_grid_desc: "Afficher la grille de fond du graphique"
+  hover_readout: "Valeurs sous le pointeur"
+  hover_readout_desc: "Affiche une ligne et la valeur de chaque canal là où pointe la souris sur le graphique"
   grid_opacity: "Opacité :"
   field_names: "Noms des champs"
   field_normalization: "Normalisation des champs"

i18n/hi.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "माउस व्हील सीधे चार्ट को ज़ूम करता है, पैन करने के बजाय"
   show_grid: "ग्रिड दिखाएं"
   show_grid_desc: "चार्ट पृष्ठभूमि ग्रिड बनाएं"
+  hover_readout: "पॉइंटर पर मान"
+  hover_readout_desc: "चार्ट पर जहाँ माउस है वहाँ एक रेखा और हर चैनल का मान दिखाएँ"
   grid_opacity: "अस्पष्टता:"
   field_names: "फ़ील्ड नाम"
   field_normalization: "फ़ील्ड नॉर्मलाइज़ेशन"

i18n/id.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "Roda mouse memperbesar grafik secara langsung daripada menggeser"
   show_grid: "Tampilkan Kisi"
   show_grid_desc: "Gambar kisi latar belakang bagan"
+  hover_readout: "Nilai di penunjuk"
+  hover_readout_desc: "Tampilkan garis dan nilai setiap kanal di tempat mouse menunjuk pada grafik"
   grid_opacity: "Opacity:"
   field_names: "Nama Field"
   field_normalization: "Normalisasi Field"

i18n/it.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "La rotella del mouse ingrandisce il grafico direttamente invece di scorrere"
   show_grid: "Mostra griglia"
   show_grid_desc: "Disegna la griglia di sfondo del grafico"
+  hover_readout: "Valori al puntatore"
+  hover_readout_desc: "Mostra una linea e il valore di ogni canale dove punta il mouse sul grafico"
   grid_opacity: "Opacità:"
   field_names: "Nomi dei Campi"
   field_normalization: "Normalizzazione Campi"

i18n/ja.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "マウスホイールでチャートを直接ズームします（パンの代わりに）"
   show_grid: "グリッドを表示"
   show_grid_desc: "チャートの背景グリッドを描画"
+  hover_readout: "ポインター位置の値"
+  hover_readout_desc: "チャート上でマウスが指す位置に線と各チャンネルの値を表示します"
   grid_opacity: "不透明度:"
   field_names: "フィールド名"
   field_normalization: "フィールド正規化"

i18n/pt-BR.yaml

@@ -70,6 +70,8 @@ settings:
   scroll_to_zoom_desc: "A roda do mouse amplia o gráfico diretamente em vez de fazer pan"
   show_grid: "Mostrar Grade"
   show_grid_desc: "Desenhar a grade de fundo do gráfico"
+  hover_readout: "Valores no ponteiro"
+  hover_readout_desc: "Mostra uma linha e o valor de cada canal onde o mouse aponta no gráfico"
   grid_opacity: "Opacidade:"
   field_names: "Nomes dos Campos"
   field_normalization: "Normalização de Campos"

i18n/pt-PT.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "A roda do rato amplia o gráfico diretamente em vez de fazer pan"
   show_grid: "Mostrar Grelha"
   show_grid_desc: "Desenhar a grelha de fundo do gráfico"
+  hover_readout: "Valores no ponteiro"
+  hover_readout_desc: "Mostra uma linha e o valor de cada canal onde o rato aponta no gráfico"
   grid_opacity: "Opacidade:"
   field_names: "Nomes dos Campos"
   field_normalization: "Normalização de Campos"

i18n/ru.yaml

@@ -92,6 +92,8 @@ settings:
   scroll_to_zoom_desc: "Колесико мыши увеличивает график напрямую вместо панорамирования"
   show_grid: "Показывать сетку"
   show_grid_desc: "Отображать координатную сетку на графике"
+  hover_readout: "Значения под указателем"
+  hover_readout_desc: "Показывает линию и значение каждого канала там, где на графике находится мышь"
   grid_opacity: "Прозрачность:"
   field_names: "Имена полей"
   field_normalization: "Нормализация полей"

i18n/ur.yaml

@@ -93,6 +93,8 @@ settings:
   scroll_to_zoom_desc: "ماؤس وہیل براہ راست چارٹ کو بڑھاتا ہے بجائے پیننگ کے"
   show_grid: "گرڈ دکھائیں"
   show_grid_desc: "چار्ट کی پس منظر کی شبکہ کھینچیں"
+  hover_readout: "پوائنٹر پر قدریں"
+  hover_readout_desc: "چارٹ پر جہاں ماؤس ہے وہاں ایک لکیر اور ہر چینل کی قدر دکھائیں"
   grid_opacity: "شفافیت:"
   field_names: "فیلڈ کے نام"
   field_normalization: "فیلڈ نارملائزیشن"

i18n/zh-CN.yaml

@@ -70,6 +70,8 @@ settings:
   scroll_to_zoom_desc: "鼠标滚轮直接缩放图表，而不是平移"
   show_grid: "显示网格"
   show_grid_desc: "绘制图表背景网格"
+  hover_readout: "指针处的数值"
+  hover_readout_desc: "在图表上鼠标所指的位置显示一条线和每个通道的数值"
   grid_opacity: "不透明度:"
   field_names: "字段名称"
   field_normalization: "字段标准化"

src/app.rs

@@ -135,6 +135,8 @@ pub struct UltraLogApp {
     pub(crate) scroll_to_zoom: bool,
     /// When true, draw the chart background grid
     pub(crate) show_grid: bool,
+    /// When true, the chart shows a line and a value box at the mouse pointer
+    pub(crate) hover_readout: bool,
     /// Grid line opacity (0..=255) used as the alpha of the base grid color
     pub(crate) grid_opacity: u8,
     // === Unit Preferences ===
@@ -278,6 +280,7 @@ impl Default for UltraLogApp {
             initial_view_seconds: 60.0, // Start with 60 second view
             scroll_to_zoom: false,
             show_grid: true,
+            hover_readout: true,
             grid_opacity: 255,
             unit_preferences: UnitPreferences::default(),
             font_scale: FontScale::default(),
@@ -340,6 +343,7 @@ impl UltraLogApp {
             language: user_settings.language,
             scroll_to_zoom: user_settings.scroll_to_zoom,
             show_grid: user_settings.show_grid,
+            hover_readout: user_settings.hover_readout,
             grid_opacity: user_settings.grid_opacity,
             unit_preferences: user_settings.unit_preferences.clone(),
             font_scale: user_settings.font_scale,
@@ -2632,6 +2636,7 @@ impl eframe::App for UltraLogApp {
             language: self.language,
             scroll_to_zoom: self.scroll_to_zoom,
             show_grid: self.show_grid,
+            hover_readout: self.hover_readout,
             grid_opacity: self.grid_opacity,
             unit_preferences: self.unit_preferences.clone(),
             font_scale: self.font_scale,

src/settings.rs

@@ -26,6 +26,10 @@ pub struct UserSettings {
     /// When true, draw the chart background grid
     #[serde(default = "default_show_grid")]
     pub show_grid: bool,
+    /// When true, the chart shows a line and a value box at the mouse pointer (issue #98).
+    /// On by default, also for settings files from before it existed.
+    #[serde(default = "default_hover_readout")]
+    pub hover_readout: bool,
     /// Grid line opacity, 0..=255. Modulates the base grid color's alpha
     /// before egui_plot's distance-based fade
     #[serde(default = "default_grid_opacity")]
@@ -106,6 +110,10 @@ fn default_show_grid() -> bool {
     true
 }
 
+fn default_hover_readout() -> bool {
+    true
+}
+
 fn default_grid_opacity() -> u8 {
     255
 }
@@ -129,6 +137,7 @@ impl Default for UserSettings {
             language: Language::default(),
             scroll_to_zoom: false,
             show_grid: default_show_grid(),
+            hover_readout: default_hover_readout(),
             grid_opacity: default_grid_opacity(),
             unit_preferences: UnitPreferences::default(),
             font_scale: FontScale::default(),

src/state.rs

@@ -646,11 +646,6 @@ impl PlotArea {
             collapsed: false,
         }
     }
-
-    /// Get the number of channels in this plot area
-    pub fn channel_count(&self) -> usize {
-        self.channel_indices.len()
-    }
 }
 
 // ============================================================================