Gemstone Crab Alert

by Andrew Coleman

1,021 installs

crab

gemstone

alert

flash

pvm

boss

GitHub ↗

Flashes the screen when Gemstone Crab health is at or below 5% with customizable color, duration, and flash speed

Documentation

Gemstone Crab Alert

A RuneLite plugin that provides visual alerts when the Gemstone Crab's health drops to critical levels. Features customizable flashing effects, health thresholds, and flash duration settings.

Features

Visual Alert System: Flashing screen overlay when Gemstone Crab health reaches your configured threshold
Customizable Flash Color: Choose any color for the alert flash (includes transparency/alpha support)
Configurable Health Threshold: Set the health percentage at which the alert triggers (default: 5%)
Adjustable Flash Duration: Control how long the alert lasts (1-30 seconds, default: 5 seconds)
Pulsing Flash Effect: Fast on/off flashing pattern (configurable speed, default: 250ms intervals)
Precise Triggering: Alerts trigger exactly when health reaches or drops below the threshold

Installation

For Development (Sideloaded Plugin)

1. Build the plugin:

``bash


   cd gemstone-crab-plugin
   ./gradlew clean jar

2. Deploy to RuneLite:

`bash


   cp build/libs/gemstone-crab-plugin-1.0.0.jar ~/.runelite/sideloaded-plugins/

3. Launch RuneLite in developer mode:

`bash


   ./launch-runelite.sh


   
   Or manually:

`bash


   ./gradlew run

4. Enable the plugin:


   - Open RuneLite settings
   - Go to Plugins
   - Find "Gemstone Crab Alert"
   - Toggle it ON
Requirements
Java 11 or higher

RuneLite client
Developer mode enabled (for sideloaded plugins)

Configuration
Access plugin settings via: RuneLite Settings → Plugins → Gemstone Crab Alert
Settings
| Setting | Default | Range | Description |
|---------|---------|-------|-------------|
| Flash Color | Red (255, 0, 0) | Color picker | The color of the screen flash alert |
| Health Threshold % | 5 | 1-99 | Alert triggers when health is at or below this percentage |
| Flash Duration (seconds) | 5 | 1-30 | Total duration of the flashing alert |
| Flash Interval (ms) | 250 | 100-1000 | Speed of on/off flashing (lower = faster) |
Recommended Settings
Fast, noticeable alert: Flash Interval = 200ms, Duration = 5 seconds

Subtle alert: Flash Interval = 500ms, Duration = 3 seconds
Long warning: Duration = 10 seconds, Flash Interval = 250ms

How It Works
1. The plugin monitors all NPCs in the game area
2. When a "Gemstone Crab" is detected, it calculates health percentage
3. If health ≤ threshold (and > 0), the flash alert activates
4. The screen flashes on/off rapidly for the configured duration
5. Alert automatically stops after the duration expires or if health recovers above threshold
Building from Source
Prerequisites
Java JDK 11 or higher

Gradle (wrapper included)

Build Steps

`bash

`Clone or download the project`


cd gemstone-crab-plugin
Build the plugin JAR

./gradlew clean jar
The JAR will be in: build/libs/gemstone-crab-plugin-1.0.0.jar

`Project Structure`


gemstone-crab-plugin/
├── src/
│   ├── main/
│   │   ├── java/com/gemstonecrab/
│   │   │   ├── GemstoneCrabPlugin.java      # Main plugin class
│   │   │   ├── GemstoneCrabConfig.java      # Configuration interface
│   │   │   └── GemstoneCrabOverlay.java     # Visual overlay renderer
│   │   └── resources/
│   │       └── runelite-plugin.properties   # Plugin metadata
│   └── test/
│       └── java/com/gemstonecrab/
│           └── GemstoneCrabPluginTest.java  # Test runner
├── build.gradle                              # Build configuration
├── settings.gradle                          # Gradle settings
└── launch-runelite.sh                       # Launch script

`Troubleshooting`

`Plugin Not Appearing`

Ensure the JAR is in ~/.runelite/sideloaded-plugins/

Verify RuneLite is running in developer mode (--developer-mode flag)


Check that only ONE copy of the plugin JAR exists
Restart RuneLite completely


Alert Not Triggering

Verify the plugin is enabled in RuneLite settings
Check that health threshold is set correctly
Ensure you're fighting a "Gemstone Crab" (exact name match)

Check RuneLite logs: ~/.runelite/logs/client.log for debug messages


Duplicate Plugin Entries

Remove any duplicate JARs from ~/.runelite/plugins/ or ~/.runelite/sideloaded-plugins/

Ensure only one runelite-plugin.properties file exists in src/main/resources/

Clean and rebuild: ./gradlew clean jar


Flash Not Visible
Check that "Flash Color" opacity/alpha is set high enough
Verify "Flash Enabled" toggle is ON (if available)
Try increasing Flash Interval for slower, more visible flashes

Technical Details

Game Tick Rate: Checks health every game tick (~0.6 seconds)

Health Calculation: (healthRatio / healthScale) * 100


Flash Pattern: Alternating on/off cycles based on Flash Interval

Config Storage: Settings saved in ~/.runelite/profiles2/ per profile


License
This plugin is provided as-is for personal use. Modify and distribute as needed.
Credits
Built for RuneLite plugin API
Uses RuneLite's overlay and configuration systems
Compatible with RuneLite 1.12.12.1+

Support
For issues or questions:

1. Check RuneLite logs: ~/.runelite/logs/client.log`

2. Verify plugin is enabled and configured correctly

3. Ensure RuneLite is up to date

4. Rebuild and redeploy if issues persist

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