digital displays

CLAUDE.md

@@ -0,0 +1,153 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is a novelty Garmin Connect IQ watchface that displays time as decimal day progress (French Revolutionary Time style) instead of traditional 12/24 hour format. The day is divided into 10 equal parts, with time displayed as a decimal from 0.0 to 10.0.
+
+**Key Concept**: The watchface converts standard time to decimal using the formula:
+```
+decimalTime = (hours + minutes/60 + seconds/3600) / 24 * 10
+```
+
+This means:
+- Midnight (00:00) → 0.0
+- 6:00 AM → 2.5
+- Noon (12:00) → 5.0
+- 6:00 PM → 7.5
+- End of day → 10.0
+
+## Development Commands
+
+### Building the Watchface
+
+The project uses the Garmin Connect IQ SDK. You need the SDK installed with `$SDK_PATH` environment variable set.
+
+**Build for simulator:**
+```bash
+$SDK_PATH/bin/monkeyc \
+    -o bin/MetricWatchFace.prg \
+    -f monkey.jungle \
+    -y $SDK_PATH/bin/developer_key
+```
+
+**Run in simulator:**
+```bash
+$SDK_PATH/bin/connectiq
+# Then load the generated .prg file in the simulator
+```
+
+**Build for specific device (example for Fenix 7):**
+```bash
+$SDK_PATH/bin/monkeyc \
+    -o bin/MetricWatchFace.prg \
+    -f monkey.jungle \
+    -d fenix7 \
+    -y $SDK_PATH/bin/developer_key
+```
+
+**Note**: The project uses `monkey.jungle` for build configuration, which references `manifest.xml` for project settings.
+
+## Architecture
+
+### Core Components
+
+**DecimalWatchFaceApp.mc** (`source/DecimalWatchFaceApp.mc:4-23`)
+- Application entry point extending `Application.AppBase`
+- Minimal setup - primarily returns the watchface view
+- No complex application state management
+
+**DecimalWatchFaceView.mc** (`source/DecimalWatchFaceView.mc:8-201`)
+- Main watchface implementation extending `WatchUi.WatchFace`
+- Handles all rendering and time calculation logic
+- Key methods:
+  - `onUpdate(dc)` - Main render loop, called every second when active
+  - `computeDecimalTime(clockTime)` - Converts standard time to decimal (0.0-10.0)
+  - `drawWatchFace(dc)` - Renders the analog face with 10 divisions, tick marks, and numbers
+  - `drawHand(dc, decimalTime)` - Draws both hour and minute hands
+  - `drawSingleHand(...)` - Helper for rendering individual hands as filled polygons
+  - `drawDigitalTime(dc, decimalTime)` - Displays decimal time as text
+
+### Rendering Architecture
+
+The watchface uses programmatic drawing (no XML layouts). All graphics are drawn using Monkey C Graphics API:
+
+1. **Watchface Circle**: 100 tick marks drawn in a loop (10 major at whole numbers 0-9, 90 minor at 0.1 intervals)
+2. **Two Hands**:
+   - **Hour hand** (red, shorter, wider): Shows which decimal unit (0-9), completes one rotation per day
+   - **Minute hand** (white, longer, thinner): Shows fractional part within current decimal unit, completes 10 rotations per day
+3. **Digital Display**: Shows exact decimal time at bottom (formatted to 2 decimal places)
+
+The hand rotation uses trigonometry with angles calculated from decimal time, offset by -90° to start at top (12 o'clock position).
+
+### Device Support
+
+The manifest (`manifest.xml`) targets 57 modern Garmin devices including:
+- Fenix series (6, 7, 8, Epix 2)
+- Forerunner series (255, 265, 645, 945, 955, 965, 970)
+- Vivoactive series (3, 4, 5, 6)
+- Venu series (2 Plus, 3, 4)
+
+All devices require Connect IQ API level 3.2.0 or higher.
+
+## Project Structure
+
+```
+MetricWatchFace/
+├── manifest.xml                      # App metadata, device compatibility
+├── monkey.jungle                     # Build configuration
+├── source/
+│   ├── DecimalWatchFaceApp.mc       # Application entry point
+│   └── DecimalWatchFaceView.mc      # Main watchface view and rendering
+└── resources/
+    ├── drawables/
+    │   ├── drawables.xml            # Drawable resource definitions
+    │   └── launcher_icon.png        # App icon (placeholder)
+    └── strings/
+        └── strings.xml              # Localized strings
+```
+
+## Important Implementation Details
+
+### Time Calculation Edge Cases
+- The decimal time formula ensures smooth progression from 0.0 to 10.0
+- The fractional part extraction (`decimalTime - decimalTime.toNumber()`) is used for the minute hand
+- Both hands update every second when the watchface is active
+
+### Drawing Performance
+- The watchface redraws completely on each `onUpdate()` call
+- 100 tick marks are drawn in every frame (major optimization opportunity)
+- Hands are drawn as filled polygons using triangle geometry
+- Center dot is redrawn after hands to ensure it's on top
+
+### Sleep Mode Handling
+- `onEnterSleep()` and `onExitSleep()` are currently empty
+- In sleep mode, the system reduces update frequency automatically
+- Consider implementing reduced complexity rendering for sleep mode
+
+## Known Technical Debt
+
+From IMPROVEMENT_IDEAS.md:
+- Launcher icon is currently a placeholder PNG
+- No screen type optimization (MIP vs AMOLED)
+- No low power mode implementation
+- Hand polygon drawing could be optimized
+- No error handling for edge cases
+- No unit tests for time conversion
+
+## Monkey C Specifics
+
+**Language**: Monkey C (Garmin's proprietary language, similar to Java/C)
+**Key APIs used**:
+- `Toybox.WatchUi.WatchFace` - Base class for watchfaces
+- `Toybox.Graphics` - Drawing primitives (drawLine, fillPolygon, drawText, etc.)
+- `Toybox.System` - System functions (getClockTime)
+- `Toybox.Time` / `Toybox.Time.Gregorian` - Time utilities
+- `Toybox.Lang` / `Toybox.Math` - Language and math utilities
+
+**Common patterns**:
+- Drawing context (`dc`) is passed to all render methods
+- Colors use `Graphics.COLOR_*` constants
+- Coordinates are in pixels, origin at top-left
+- All trigonometry uses radians (convert with `Math.toRadians()`)

IMPROVEMENT_IDEAS.md

@@ -8,7 +8,7 @@ This document contains potential enhancements and features to improve the decima
 
 ### 1. Better Graphics & Styling
 - **Proper launcher icon** - Replace placeholder with actual designed icon
-- **Sub-divisions/minor tick marks** - Add marks at 0.5 intervals for finer precision
+- **Sub-divisions/minor tick marks** - Add marks at 0.5 intervals for finer precision (/)
 - **Color themes**
   - Dark mode / Light mode
   - "Metric blue/orange" scheme

resources/properties.xml

@@ -0,0 +1,5 @@
+<properties>
+    <property id="UseFiveHourMode" type="boolean">false</property>
+    <property id="Show12HourShadow" type="boolean">false</property>
+    <property id="ShowNumericTime" type="boolean">true</property>
+</properties>

resources/settings/settings.xml

@@ -0,0 +1,11 @@
+<settings>
+    <setting propertyKey="@Properties.UseFiveHourMode" title="@Strings.FiveHourModeTitle">
+        <settingConfig type="boolean" />
+    </setting>
+    <setting propertyKey="@Properties.Show12HourShadow" title="@Strings.Show12HourShadowTitle">
+        <settingConfig type="boolean" />
+    </setting>
+    <setting propertyKey="@Properties.ShowNumericTime" title="@Strings.ShowNumericTimeTitle">
+        <settingConfig type="boolean" />
+    </setting>
+</settings>

resources/strings/strings.xml

@@ -1,3 +1,6 @@
 <strings>
     <string id="AppName">Decimal Day</string>
+    <string id="FiveHourModeTitle">5-Hour Mode</string>
+    <string id="Show12HourShadowTitle">12 Hour Shadow</string>
+    <string id="ShowNumericTimeTitle">Show Numeric Time</string>
 </strings>

source/DecimalWatchFaceView.mc

@@ -4,11 +4,34 @@ using Toybox.System;
 using Toybox.Lang;
 using Toybox.Time;
 using Toybox.Time.Gregorian;
+using Toybox.Application;
 
 class DecimalWatchFaceView extends WatchUi.WatchFace {
 
+    var isHighPowerMode = true; // Track if we're in high power mode
+
+    // Custom colors for AMOLED-friendly shadows
+    const VERY_DARK_RED = 0x330000;    // #330000
+    const VERY_DARK_GRAY = 0x333333;   // #333333
+
+    var useAmoledColors = false;       // Whether to use darker colors
+
     function initialize() {
         WatchFace.initialize();
+
+        // Check if device likely has AMOLED screen
+        // AMOLED devices typically support always-on display and higher color depths
+        var deviceSettings = System.getDeviceSettings();
+
+        // Check if device supports always-on display (common on AMOLED)
+        // or if we can detect high color support
+        if (deviceSettings has :requiresBurnInProtection) {
+            useAmoledColors = deviceSettings.requiresBurnInProtection;
+        } else {
+            // Fallback: use darker colors if device has round screen (most AMOLED watches)
+            // This is a heuristic, but safer to use dark colors on all devices
+            useAmoledColors = true; // Use darker colors by default for burn-in protection
+        }
     }
 
     // Load your resources here
@@ -28,18 +51,44 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
         var clockTime = System.getClockTime();
         var decimalTime = computeDecimalTime(clockTime);
 
+        // Check settings
+        var useFiveHourMode = Application.Properties.getValue("UseFiveHourMode");
+        var show12HourShadow = Application.Properties.getValue("Show12HourShadow");
+        var showNumericTime = Application.Properties.getValue("ShowNumericTime");
+        var displayTime = decimalTime;
+        var isMorning = true;
+
+        if (useFiveHourMode) {
+            // Convert 0-10 to 0-5 twice per day
+            if (decimalTime >= 5.0) {
+                displayTime = decimalTime - 5.0;
+                isMorning = false; // Afternoon
+            } else {
+                displayTime = decimalTime;
+                isMorning = true; // Morning
+            }
+        }
+
         // Clear the screen
         dc.setColor(Graphics.COLOR_BLACK, Graphics.COLOR_BLACK);
         dc.clear();
 
-        // Draw the watchface
-        drawWatchFace(dc);
+        // Draw the watchface (circle, ticks, numbers)
+        drawWatchFace(dc, useFiveHourMode, isMorning);
 
-        // Draw the hand
-        drawHand(dc, decimalTime);
+        // Draw digital time displays (before hands so hands appear on top)
+        if (showNumericTime) {
+            // Draw decimal time at bottom
+            drawDigitalTime(dc, decimalTime);
 
-        // Draw digital time display
-        drawDigitalTime(dc, decimalTime);
+            // If 12-hour shadow is also enabled, draw traditional time at top
+            if (show12HourShadow) {
+                drawTraditionalTime(dc, clockTime);
+            }
+        }
+
+        // Draw the hands last (on top of everything)
+        drawHand(dc, displayTime, useFiveHourMode, show12HourShadow, clockTime);
     }
 
     // Called when this View is removed from the screen. Save the
@@ -50,10 +99,12 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
 
     // The user has just looked at their watch. Timers and animations may be started here.
     function onExitSleep() {
+        isHighPowerMode = true;
     }
 
     // Terminate any active timers and prepare for slow updates.
     function onEnterSleep() {
+        isHighPowerMode = false;
     }
 
     // Compute decimal time from current clock time
@@ -70,7 +121,7 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
     }
 
     // Draw the watchface circle, tick marks, and numbers
-    function drawWatchFace(dc) {
+    function drawWatchFace(dc, useFiveHourMode, isMorning) {
         var width = dc.getWidth();
         var height = dc.getHeight();
         var centerX = width / 2;
@@ -79,10 +130,14 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
 
         dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_TRANSPARENT);
 
+        // Determine scale based on mode (5 or 10 hour)
+        var maxValue = useFiveHourMode ? 5.0 : 10.0;
+        var tickCount = useFiveHourMode ? 50 : 100; // 0.1 intervals
+
         // Draw tick marks at 0.1 intervals (major at whole numbers, minor at 0.1)
-        for (var i = 0; i < 100; i++) {
+        for (var i = 0; i < tickCount; i++) {
             var decimalValue = i * 0.1;
-            var angle = (decimalValue / 10.0) * 360.0 - 90.0; // -90 to start at top
+            var angle = (decimalValue / maxValue) * 360.0 - 90.0; // -90 to start at top
             var angleRad = Math.toRadians(angle);
 
             // Determine if this is a major tick (whole number) or minor tick
@@ -104,9 +159,29 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
             if (isMajor) {
                 var numberX = centerX + (radius - 38) * Math.cos(angleRad);
                 var numberY = centerY + (radius - 38) * Math.sin(angleRad);
-                var numberValue = (i / 10).toNumber(); // Convert to 0-9
-                if (numberValue == 0) {
-                    numberValue = 10; // Display 10 instead of 0
+                var numberValue = (i / 10).toNumber(); // Position 0-4 or 0-9
+
+                if (useFiveHourMode) {
+                    // 5-hour mode: show different numbers based on morning/afternoon
+                    if (isMorning) {
+                        // Morning: show 5,1,2,3,4 (5 at top, then 1,2,3,4)
+                        if (numberValue == 0) {
+                            numberValue = 5;
+                        }
+                        // else numberValue stays as 1,2,3,4
+                    } else {
+                        // Afternoon: show 10,6,7,8,9 (10 at top, then 6,7,8,9)
+                        if (numberValue == 0) {
+                            numberValue = 10;
+                        } else {
+                            numberValue = numberValue + 5; // 1->6, 2->7, 3->8, 4->9
+                        }
+                    }
+                } else {
+                    // 10-hour mode: show 10 at top instead of 0
+                    if (numberValue == 0) {
+                        numberValue = 10;
+                    }
                 }
 
                 dc.setColor(Graphics.COLOR_WHITE, Graphics.COLOR_TRANSPARENT);
@@ -120,29 +195,67 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
             }
         }
 
-        // Draw center dot
-        dc.fillCircle(centerX, centerY, 5);
+        // Note: Center dot is drawn in drawHand() to ensure it's on top of everything
     }
 
-    // Draw both hour and minute hands for current decimal time
-    function drawHand(dc, decimalTime) {
+    // Draw hour, minute, and second hands for current decimal time
+    function drawHand(dc, decimalTime, useFiveHourMode, show12HourShadow, clockTime) {
         var width = dc.getWidth();
         var height = dc.getHeight();
         var centerX = width / 2;
         var centerY = height / 2;
         var radius = (width < height ? width : height) / 2 - 10;
 
-        // Calculate hour hand (shows which decimal unit 0-9, one rotation per day)
-        var hourAngle = (decimalTime / 10.0) * 360.0 - 90.0;
-        var hourAngleRad = Math.toRadians(hourAngle);
+        // Draw traditional 12-hour shadow hands first (if enabled), so they appear behind
+        if (show12HourShadow) {
+            var hour = clockTime.hour;
+            var minute = clockTime.min;
+
+            // Calculate traditional 12-hour hand angle
+            var traditional12HourAngle = ((hour % 12) + (minute / 60.0)) / 12.0 * 360.0 - 90.0;
+            var traditional12HourLength = radius - 70; // Same as decimal hour hand
+
+            // Calculate traditional 60-minute hand angle
+            var traditional60MinuteAngle = (minute / 60.0) * 360.0 - 90.0;
+            var traditional60MinuteLength = radius - 45; // Same as decimal minute hand
+
+            // Choose colors based on screen type (darker for AMOLED burn-in protection)
+            var shadowGray = useAmoledColors ? VERY_DARK_GRAY : Graphics.COLOR_DK_GRAY;
+            var shadowRed = useAmoledColors ? VERY_DARK_RED : Graphics.COLOR_DK_RED;
+
+            // Draw traditional minute hand (dark gray)
+            drawSingleHand(dc, centerX, centerY, traditional60MinuteAngle, traditional60MinuteLength, 4, shadowGray);
+
+            // Draw traditional hour hand (dark red)
+            drawSingleHand(dc, centerX, centerY, traditional12HourAngle, traditional12HourLength, 6, shadowRed);
+        }
+
+        // Adjust scale based on mode
+        var maxValue = useFiveHourMode ? 5.0 : 10.0;
+
+        // Calculate hour hand (shows which decimal unit)
+        // In 10-hour mode: one rotation per day
+        // In 5-hour mode: two rotations per day
+        var hourAngle = (decimalTime / maxValue) * 360.0 - 90.0;
         var hourHandLength = radius - 70; // Shorter hand
 
-        // Calculate minute hand (shows fractional part, 10 rotations per day)
+        // Calculate minute hand (shows fractional part)
         var fractionalPart = decimalTime - decimalTime.toNumber(); // Get decimal part
         var minuteAngle = fractionalPart * 360.0 - 90.0;
-        var minuteAngleRad = Math.toRadians(minuteAngle);
         var minuteHandLength = radius - 45; // Longer hand
 
+        // Calculate second hand (shows finer detail)
+        // Only visible in high power mode
+        var multiplier = 100.0; // 0.01 increments
+        var secondFractionalPart = (decimalTime * multiplier) - (decimalTime * multiplier).toNumber();
+        var secondAngle = secondFractionalPart * 360.0 + 90.0;
+        var secondHandLength = radius - 35; // Longest hand
+
+        // Draw second hand first (if in high power mode), so it appears behind other hands
+        if (isHighPowerMode) {
+            drawSingleHand(dc, centerX, centerY, secondAngle, secondHandLength, 2, Graphics.COLOR_YELLOW);
+        }
+
         // Draw minute hand (longer, thinner)
         drawSingleHand(dc, centerX, centerY, minuteAngle, minuteHandLength, 4, Graphics.COLOR_WHITE);
 
@@ -198,4 +311,35 @@ class DecimalWatchFaceView extends WatchUi.WatchFace {
             Graphics.TEXT_JUSTIFY_CENTER | Graphics.TEXT_JUSTIFY_VCENTER
         );
     }
+
+    // Draw traditional 12-hour time display
+    function drawTraditionalTime(dc, clockTime) {
+        var width = dc.getWidth();
+        var height = dc.getHeight();
+
+        var hour = clockTime.hour;
+        var minute = clockTime.min;
+
+        // Convert to 12-hour format
+        var hour12 = hour % 12;
+        if (hour12 == 0) {
+            hour12 = 12;
+        }
+
+        // Format as HH:MM
+        var timeString = hour12.format("%d") + ":" + minute.format("%02d");
+
+        // Choose color based on screen type (darker for AMOLED burn-in protection)
+        var shadowGray = useAmoledColors ? VERY_DARK_GRAY : Graphics.COLOR_DK_GRAY;
+
+        // Draw at top center in dark gray
+        dc.setColor(shadowGray, Graphics.COLOR_TRANSPARENT);
+        dc.drawText(
+            width / 2,
+            height * 0.25,
+            Graphics.FONT_LARGE,
+            timeString,
+            Graphics.TEXT_JUSTIFY_CENTER | Graphics.TEXT_JUSTIFY_VCENTER
+        );
+    }
 }