Day & Night Cycle Plugin

A RuneLite plugin that adds a dynamic day/night cycle to Old School RuneScape. Sky colors shift in real time based on astronomical sunrise/sunset calculations for your chosen geographic location.

Demo

sunrise.mp4

sunset.mp4

Features

• Real-Time Sky Cycle — Skybox colors follow actual sunrise and sunset times computed from geographic coordinates
• 44 Pre-Configured Cities — Spanning 6 continents, each with correct timezone and coordinates
• Custom Coordinates — Input any latitude/longitude for location-accurate calculations
• Custom Time Override — Set a specific virtual time (HH:MM:SS)
• Fast Test Mode — Compress a full day/night cycle into a configurable duration (default 20s)
• Smooth Color Interpolation — Sine-curve blending with two-phase transitions for natural color progression
• Customizable Colors — Configure sunrise, day, sunset, and night colors independently
• Virtual Time Overlay — On-screen display of the current virtual time

How It Works

The plugin uses an astronomical algorithm (Williams' method) to compute exact sunrise/sunset times for the selected location. Sky color is then interpolated across four phases — night, sunrise, day, sunset — with 30-minute transition buffers and sine-curve smoothing for realistic gradients.

Tech Stack

• Java 11
• RuneLite Plugin API
• Gradle
• Lombok

Build & Install

git clone https://github.com/rodhfr/DayNightCycle.git
cd DayNightCycle
./gradlew build

To test locally with RuneLite:

./gradlew run

To install in RuneLite, place the built JAR in the plugin directory and enable "Day-Night Cycle" in settings.

Project Structure

DayNightCycle/
├── src/main/java/com/example/
│   ├── DayNightCyclePlugin.java    # Main plugin — rendering, sun calculation, color blending
│   ├── DayNightCycleConfig.java    # Configuration interface — cities, colors, time modes
│   └── DayNightCycleOverlay.java   # Virtual time HUD overlay
├── src/test/java/com/example/
│   ├── ExamplePluginTest.java      # Test launcher
│   └── Mainrunner.java             # Alternative test launcher
├── build.gradle
├── runelite-plugin.properties
└── LICENSE                         # BSD 2-Clause

Legal

This is a modification of the original Skybox plugin. All copyright from the original author is maintained.

License

BSD 2-Clause — see LICENSE.