XY Color Space Implementation Summary

Changes Made to EntityControl.qml

1. Added XY Color Space Properties

• supportsXy: Detects XY color mode support
• currentXyColor: Current XY coordinates from entity state
• currentHue: Converted hue value (0-360°)
• currentSaturation: Converted saturation value (0-1)

2. Updated Advanced Controls Detection

• Modified hasAdvancedControls to include supportsXy

3. New XY Color Control UI Section

// XY Color Control (CIE 1931) with HUE Slider
ColumnLayout {
    visible: supportsXy && isOn
    // Hue slider with rainbow gradient
    // Saturation slider with dynamic gradient
    // XY color preset buttons (6 colors)
    // Current XY color indicator
}

4. Added Entity Information Display

• Shows current XY coordinates in format “(x.xxxx, y.yyyy)”
• Only visible when XY color data is available

5. Implemented Color Conversion Functions

• xyToRgb(x, y): XY to RGB conversion with proper sRGB transformation
• xyToRgbColor(x, y): XY to Qt color object
• xyToHue(x, y): XY to HSV hue conversion
• xyToSaturation(x, y): XY to HSV saturation conversion
• hueToXy(hue, saturation): HSV to XY conversion
• hueToRgbColor(hue): Hue to RGB color for gradients

6. Updated Import Statements

• Fixed missing version numbers in Qt/KDE imports

Key Features

Hue Slider

• Range: 0-360 degrees
• Rainbow gradient background showing color spectrum
• Real-time XY coordinate updates on change

Saturation Slider

• Range: 0-100%
• Gradient from white to current hue at full saturation
• Dynamic gradient updates based on current hue

Color Presets

• 6 carefully chosen XY coordinates for common colors
• Visual highlight when current color matches preset
• Tooltips showing color name and XY coordinates

Current Color Display

• Shows current XY coordinates with 4-decimal precision
• Color preview rectangle with proper text contrast
• Automatically calculates best text color (black/white)

Technical Implementation

Color Space Accuracy

• Uses proper CIE 1931 XY chromaticity coordinates
• sRGB transformation matrices for accurate conversion
• Gamma correction for proper color representation
• D65 white point as fallback ([0.3127, 0.3290])

Performance Optimizations

• Color conversions only calculated when needed
• Slider value clamping to valid ranges
• Efficient gradient generation for smooth UI

Home Assistant Integration

• Sends xy_color parameter to light.turn_on service
• Compatible with Philips Hue, LIFX, and other XY-capable lights
• Maintains compatibility with existing RGB/CCT modes

Files Created

1. XY_COLOR_DOCUMENTATION.md - Comprehensive documentation
2. XY_COLOR_EXAMPLES.js - Usage examples and test code

Compatibility

• Works with existing EntityControl configurations
• Automatically shows/hides based on light capabilities
• No breaking changes to existing functionality
• Supports lights with multiple color modes (RGB + XY + CCT)

Testing

• Mock entity state examples provided
• Color conversion test functions included
• Common XY coordinates reference table
• Gamut validation foundation for future enhancements