Okay, let's start building a simplified web version of the classic game Qix (1981). This initial version will include the player (Marker), the Qix, drawing Stix, and basic collision detection. We'll use HTML Canvas and JavaScript.

This sets up the basic structure:

1. HTML: Creates a canvas and displays score, claimed percentage, and lives.
2. CSS: Styles the page elements.
3. JavaScript:
   • Initializes the canvas and game variables.
   • Handles keyboard input for player movement (arrow keys). Movement is restricted to the border unless drawing.
   • Starts drawing Stix when the player moves away from the border.
   • Stops drawing and calculates a placeholder score/claim when the player returns to the border.
   • Implements a basic Qix made of connected line segments that move towards random target points and bounce off walls.
   • Includes basic collision detection: Qix hitting the Stix being drawn, or the player hitting the Qix while drawing.
   • Implements a simple life system and game over state.
   • Includes a pause feature (press 'P').
   • Contains the main game loop (requestAnimationFrame).

To Play:

• Use the Arrow Keys to move the player along the border.
• Move away from the border using an arrow key to start drawing a line (Stix).
• Return to any border edge to complete the shape.
• Avoid letting the Qix (cyan lines) touch your Stix while drawing.
• Avoid touching the Qix yourself while drawing.
• Press 'P' to pause/resume.

This is a starting point. Features like Sparx, accurate area filling, different Qix behaviors, levels, and more refined collision/movement require significant additional logic.*

Okay, let's tackle the "Claimed" percentage calculation and add some general improvements. Calculating and filling the claimed area accurately is the most significant change here.

We'll implement:

1. Actual Area Calculation: When the player completes a shape, we'll determine the polygon formed by the Stix and the border, calculate its area, and update the percentage.
2. Area Filling: Visually fill the claimed areas on the canvas.
3. Fuse: Add a "Fuse" that travels along the Stix while the player is drawing. If the player stops moving while drawing, the Fuse appears and moves towards the player. Collision with the Fuse results in losing a life.
4. Sparx: Add simple "Sparx" enemies that patrol the border. Collision with Sparx results in losing a life.
5. Refined Collision: Improve collision checks slightly.
6. Visual Tweaks: Minor visual adjustments.

This involves significant additions to the JavaScript logic.

Key Changes and Improvements:

1. Modular Structure: Code is split into modules (game.js, player.js, qix.js, sparx.js, config.js, utils.js) for better organization.
2. Configuration File (config.js): Centralized place for game parameters (speeds, colors, sizes, etc.).
3. Utility Functions (utils.js): Common functions like collision checks, geometry calculations, etc., are separated.
4. Area Filling (Basic):
   • The claimArea function now calculates the area of the polygon formed by the Stix (using polygonArea).
   • It adds the calculated area to totalClaimedArea and updates claimedPercentage.
   • The draw function fills these claimed polygons using config.fillColor.
   • Limitation: The logic to correctly form the polygon using the border (getBorderPath) is still a placeholder and complex to implement perfectly. The current version might not always fill the correct side or shape accurately, but it demonstrates the mechanism.
5. Sparx: Two Sparx enemies are added, patrolling the border in opposite directions. Collision with them while the player is on the border results in losing a life.
6. Fuse: If the player stops moving while drawing a Stix for a set duration (config.fuseDelay), a Fuse appears at the start of the Stix and travels towards the player. Collision with the Fuse is fatal.
7. Refined Movement: Player movement logic is adjusted to handle border constraints and drawing initiation more carefully. Prevents backtracking along the stix.
8. Improved Collision: Uses pointLineSegmentDistance for more accurate player-Qix collision checks.
9. Game States: Clearer handling of paused, gameOver, and gameWon states. Added a restart ('R') option.
10. Visuals: Updated CSS for a slightly darker theme. Border is now drawn dynamically on the canvas. Added game over/win messages.

Further Potential Improvements (Not Implemented):

• Accurate Polygon Formation: The most critical missing piece for perfect area filling is robustly calculating the border path between the Stix start/end points to form the correct two polygons.
• Qix/Fill Collision: Preventing the Qix from crossing into filled areas.
• Level Progression: Increasing difficulty, changing Qix/Sparx behavior.
• Scoring Details: More nuanced scoring (e.g., bonus for fast completion).
• Sound Effects.
• Mobile Controls.