---
title: Squares²
tags:
- demoArt
---
{% layout 'hippie/simple.liquid' %}

{% block style %}
<style>
	canvas {
		display: block;
	}
</style>
{% endblock %}

{% block body %}{% endblock %}

{% block script %}
<script>
	function fillCanvasWithSquares(maxSquareSize = 128, minSquareSize = 8, largeSquarePercentage = 40) {
		const canvas = document.createElement('canvas');
		canvas.width = window.innerWidth;
		canvas.height = window.innerHeight;
		document.body.appendChild(canvas);

		const ctx = canvas.getContext('2d');
		const colors = [
			'#fad803', '#d30a51', '#273f8b',
			'#b7e0f0', '#52bed1', '#0c85ff'
		];

		function isPowerOfTwo(n) {
			return n > 0 && (n & (n - 1)) === 0;
		}

		if (!isPowerOfTwo(maxSquareSize) || !isPowerOfTwo(minSquareSize)) {
			console.error('Both sizes must be powers of 2');
			return;
		}

		let grid = Array(Math.ceil(canvas.height / minSquareSize))
			.fill(null)
			.map(() => Array(Math.ceil(canvas.width / minSquareSize)).fill(false));

		function canPlace(gridX, gridY, sizeInCells) {
			if (gridY + sizeInCells > grid.length || gridX + sizeInCells > grid[0].length) return false;
			for (let y = gridY; y < gridY + sizeInCells; y++) {
				for (let x = gridX; x < gridX + sizeInCells; x++) {
					if (grid[y][x]) return false;
				}
			}
			return true;
		}

		function markOccupied(gridX, gridY, sizeInCells) {
			for (let y = gridY; y < gridY + sizeInCells; y++) {
				for (let x = gridX; x < gridX + sizeInCells; x++) {
					grid[y][x] = true;
				}
			}
		}

		function draw(gridX, gridY, sizeInPixels) {
			const x = gridX * minSquareSize;
			const y = gridY * minSquareSize;
			ctx.fillStyle = colors[Math.floor(Math.random() * colors.length)];
			ctx.fillRect(x, y, sizeInPixels, sizeInPixels);
			ctx.strokeStyle = '#333';
			ctx.lineWidth = 1;
			ctx.strokeRect(x, y, sizeInPixels, sizeInPixels);
		}

		function fill() {
			const largestSizeInCells = maxSquareSize / minSquareSize;

			// Collect and shuffle positions for largest squares
			const positions = [];
			for (let gridY = 0; gridY < grid.length; gridY++) {
				for (let gridX = 0; gridX < grid[0].length; gridX++) {
					if (canPlace(gridX, gridY, largestSizeInCells)) {
						positions.push({ gridX, gridY });
					}
				}
			}
			positions.sort(() => Math.random() - 0.5);

			// Place largest squares up to percentage
			const target = Math.floor(positions.length * largeSquarePercentage / 100);
			for (let i = 0; i < target; i++) {
				const { gridX, gridY } = positions[i];
				if (canPlace(gridX, gridY, largestSizeInCells)) {
					markOccupied(gridX, gridY, largestSizeInCells);
					draw(gridX, gridY, maxSquareSize);
				}
			}

			// Fill remaining space with smaller sizes
			for (let size = maxSquareSize / 2; size >= minSquareSize; size /= 2) {
				const cellSize = size / minSquareSize;
				for (let gridY = 0; gridY < grid.length; gridY++) {
					for (let gridX = 0; gridX < grid[0].length; gridX++) {
						if (canPlace(gridX, gridY, cellSize)) {
							markOccupied(gridX, gridY, cellSize);
							draw(gridX, gridY, size);
						}
					}
				}
			}
		}

		fill();

		window.addEventListener('resize', () => {
			canvas.width = window.innerWidth;
			canvas.height = window.innerHeight;
			grid = Array(Math.ceil(canvas.height / minSquareSize))
				.fill(null)
				.map(() => Array(Math.ceil(canvas.width / minSquareSize)).fill(false));
			ctx.clearRect(0, 0, canvas.width, canvas.height);
			fill();
		});
	}

	fillCanvasWithSquares(128, 8, 10);
</script>
{% endblock %}