Sunsetr v0.5.0 Release Notes

🌍 Geographic Location-Based Transitions

The headline feature of v0.5.0 is comprehensive geographic location support, bringing natural, location-aware color temperature transitions that automatically adjust throughout the year.

Interactive City Selection

Run sunsetr --geo to launch an interactive fuzzy search interface featuring:

• 10,000+ cities worldwide with precise coordinates
• Smart search by city name, country, or region
• Automatic timezone detection for accurate local sunset/sunrise times

Automatic Location Detection

When you first run sunsetr without selecting a city, it intelligently detects your approximate location using:

• System timezone analysis with multiple fallback methods
• 466 timezone-to-coordinate mappings covering the entire globe

Enhanced Solar Calculations

The new geographic mode (transition_mode = "geo") provides:

• Precise solar calculations using +10° to -2° sun elevation angles
• Bézier curve transitions for more natural color temperature changes
• Extreme latitude support with special handling for polar regions
• Year-round accuracy with automatic seasonal adjustments

Debug Solar Information

Run sunsetr --debug to see detailed calculations for your location:

[LOG] Solar calculation details:
┃           Raw coordinates: 29.4241°, -98.4936°
┃               Sunrise UTC: 11:35
┃                Sunset UTC: 01:37
┃       Coordinate Timezone: America/Chicago (-05:00)
┃   --- Sunset (descending) ---
┃   Transition start (+10°): 19:51:57
┃   Golden hour start (+6°): 20:10:07
┃               Sunset (0°): 20:37:21
┃      Transition end (-2°): 20:46:25
┃          Civil dusk (-6°): 21:04:35
┃            Night duration: 9 hours 40 minutes
┃   --- Sunrise (ascending) ---
┃          Civil dawn (-6°): 06:08:37
┃    Transition start (-2°): 06:26:46
┃              Sunrise (0°): 06:35:51
┃     Golden hour end (+6°): 07:03:05
┃     Transition end (+10°): 07:21:14
┃              Day duration: 12 hours 30 minutes
┃           Sunset duration: 54 minutes
┃          Sunrise duration: 54 minutes
┃
[LOG] Next transition will begin at: 06:26:45 Night   → Sunrise 󰖜

🔄 Live Configuration Reload

New --reload command allows instant configuration updates without restarting:

sunsetr --reload

• Preserves current transition state
• Applies new settings immediately
• Works with running instances via signal handling

🧪 Interactive Temperature Testing

Test different color temperatures and gamma values with the new --test command:

sunsetr --test 3300 90  # Warm night time values
# Press ESC or Ctrl+C to restore previous settings

Signal-Based Architecture Improvements

Enhanced Process Communication

• SIGUSR2: Configuration reload signal
• SIGUSR1: Test mode activation
• Zero-polling event-driven redesign for CPU efficiency

Robust Lock File Mechanism

• Automatic stale lock detection and cleanup
• Cross-compositor awareness

Additional Improvements

Performance Optimizations

• Event-driven main loop eliminates unnecessary CPU wake-ups
• Intelligent state tracking prevents redundant backend updates
• Parallel operations for configuration reload and gamma reset

Enhanced Error Handling

• Clearer error messages with actionable guidance
• Graceful fallback for location detection failures
• Improved signal handler stability with comprehensive lifecycle tracking

Process Management

• PR_SET_PDEATHSIG ensures hyprsunset cleanup on parent death
• Process group isolation for proper signal handling
• Compositor-native spawning for correct parent-child relationships

Configuration Changes

New installations now default to geographic mode:

transition_mode = "geo"  # Automatic sunrise/sunset based on location
latitude = 40.7128       # Auto-detected or set via --geo
longitude = -74.0060     # Use sunsetr --geo to update

Bug Fixes

• Fixed gamma persistence when switching between compositors (use sunetr --reload if needed)
• Resolved signal handling race conditions
• Corrected lock file truncation issue
• Fixed hyprsunset cleanup on forceful termination
• Improved parent death monitoring reliability

Documentation

• Comprehensive rustdoc comments throughout codebase
• Detailed implementation notes in IMPLEMENTATION_CHANGES.md
• Updated README with geo mode instructions
• Added extensive test coverage for lock mechanisms

Full Changelog: v0.4.0...v0.5.0

Installation:

• Build from source: cargo build --release
• AUR: paru -S sunsetr-bin

Upgrade Notes:

• Existing configurations remain compatible
• Run sunsetr --geo to enable location-based transitions
• New --reload and --test commands available immediately