examples/continuous-src.html

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<html>

<head>
	<meta charset="utf-8" />
	<title>circlepacker continuous rendering demo</title>
	<link rel="stylesheet" href="./example.css" />
</head>

<body>
	<article class="text">
		<h1>continuous drawing</h1>
		<p>the circle positions are continuously updated. you can use the buttons below to update the circles and
			restart the animation. you can also drag circles around.</p>
		<p>this example uses the development version of the circlepacker script: it runs the code as-is, without any
			build step. it is mostly useful for development purposes.</p>
		<p><a href="index.html">back to index</a></p>
	</article>
	<div class="container container--is-interactive"></div>
	<div class="buttons">
		<button id="add-circle">add circle</button>
		<button id="delete-circle">delete circle</button>
		<button id="random-size">random size</button>
		<button id="random-target">random target</button>
		<button id="pin-random">toggle pin</button>
	</div>
	<div class="range-container">
		<label for="damping">damping</label>
		<input id="damping" type="range" min="0" max="0.05" step="0.001" value="0.025" />
		<span id="damping-value">0.025</span>
	</div>
	<script type="module">
		import { CirclePacker } from '../src/circlepacker.js';

		const DRAG_THRESOLD = 10;

		const containerEl = document.querySelector('.container');
		const addButtonEl = document.querySelector('#add-circle');
		const deleteButtonEl = document.querySelector('#delete-circle');
		const randomButtonEl = document.querySelector('#random-size');
		const targetButtonEl = document.querySelector('#random-target');
		const pinRandomButtonEl = document.querySelector('#pin-random');
		const dampingInputEl = document.querySelector('#damping');
		const dampingValueEl = document.querySelector('#damping-value');

		// references to all circle elements
		const circleEls = {};

		// dimenstions of container
		const rect = containerEl.getBoundingClientRect();
		let bounds = { width: rect.width, height: rect.height };
		let target = { x: bounds.width / 2, y: bounds.height / 2 };

		let isDragging = false;
		let pinnedCircleId = null;

		const circles = [
			createCircle(),
			createCircle(),
			createCircle(),
			createCircle(),
			createCircle()
		];

		const targetEl = createTargetEl();

		const packer = new CirclePacker({
			bounds,
			target,
			circles,
			onMove: render,
			collisionPasses: 3,
			centeringPasses: 2,
			correctionPasses: 5,
			animationLoop: true,

			// the path to the worker file from the current location
			workerPath: '../src/CirclePackWorker.js'
		});

		addButtonEl.addEventListener('click', addRandomCircle);
		deleteButtonEl.addEventListener('click', removeRandomCircle);
		randomButtonEl.addEventListener('click', setRandomBounds);
		targetButtonEl.addEventListener('click', setRandomTarget);
		pinRandomButtonEl.addEventListener('click', toggleRandomCirclePin);
		dampingInputEl.addEventListener('input', setDamping);

		function addRandomCircle() {
			packer.addCircle(createCircle());
		}

		// create circle dom object, return circle data
		function createCircle(x, y, radius) {
			radius = radius || random(10, 40);
			x = x || random(radius, bounds.width - radius);
			y = y || random(radius, bounds.height - radius);

			const diameter = radius * 2;
			const circleEl = document.createElement('div');

			// need some sort of unique id...
			const id = 'circle-' + random(0, 1000, true) + '-' + Date.now();

			const circle = {
				id: id,
				radius: radius,
				position: {
					x: random(radius, bounds.width - radius),
					y: random(radius, bounds.height - radius)
				}
			};

			// create circle el

			circleEl.id = id;
			circleEl.style.width = diameter + 'px';
			circleEl.style.height = diameter + 'px';
			circleEl.style.borderRadius = diameter + 'px';
			circleEl.classList.add('circle');

			// store position for dragging
			circleEl.setAttribute('data-x', x);
			circleEl.setAttribute('data-y', y);
			circleEl.setAttribute('data-radius', radius);

			// start dragging
			circleEl.addEventListener('mousedown', function (event) {
				circlePressed(circleEl, circle, event);
			});

			containerEl.appendChild(circleEl);

			circleEls[id] = circleEl;

			return circle;
		}

		function createTargetEl() {
			const targetEl = document.createElement('div');
			targetEl.classList.add('target');

			containerEl.appendChild(targetEl);

			return targetEl;
		}

		function removeRandomCircle() {
			const ids = Object.keys(circleEls);
			const idToDelete = ids[random(0, ids.length, true)];

			removeCircle(idToDelete);
		}

		function setRandomBounds() {
			bounds = {
				width: random(200, 500, true),
				height: random(200, 500, true)
			};

			containerEl.style.width = bounds.width + 'px';
			containerEl.style.height = bounds.height + 'px';

			packer.setBounds(bounds);

			// set attraction target to center of new bounds
			target = { x: bounds.width / 2, y: bounds.height / 2 };
			packer.setTarget(target);
			packer.update();
		}

		function removeCircle(id) {
			packer.removeCircle(id);

			requestAnimationFrame(function () {
				containerEl.removeChild(circleEls[id]);
				delete circleEls[id];
			});
		}

		function toggleRandomCirclePin() {
			if (pinnedCircleId) {
				packer.unpinCircle(pinnedCircleId);
				circleEls[pinnedCircleId].classList.remove('is-pinned');
				pinnedCircleId = null;
			} else {
				if (circles.length) {
					const randomCircleIndex = Math.floor(Math.random() * circles.length);
					const randomCircle = circles[randomCircleIndex];

					pinnedCircleId = randomCircle.id;
					circleEls[pinnedCircleId].classList.add('is-pinned');
					packer.pinCircle(randomCircle);
				}
			}
		}

		function setRandomTarget() {
			target = {
				x: random(0, bounds.width, true),
				y: random(0, bounds.height, true)
			};

			packer.setTarget(target);
			packer.update();
		}

		function setDamping() {
			const damping = parseFloat(dampingInputEl.value);
			dampingValueEl.textContent = damping.toFixed(4);
			packer.setDamping(damping);
		}

		function render(circles) {
			requestAnimationFrame(function () {
				for (let id in circles) {
					const circleEl = circleEls[id];

					if (circleEl) {
						const circle = circles[id];
						const x = circle.position.x - circle.radius;
						const y = circle.position.y - circle.radius;

						// store position for dragging
						circleEl.setAttribute('data-x', x);
						circleEl.setAttribute('data-y', y);

						// actually move the circles around
						circleEl.style.transform = `translateX(${x}px) translateY(${y}px)`;
						circleEl.classList.add('is-visible');
					}
				}

				targetEl.style.transform = `translateX(${target.x}px) translateY(${target.y}px)`
			});
		}

		// start and stop dragging
		function circlePressed(circleEl, circle, event) {
			const circleStartPos = {
				x: parseFloat(circleEl.getAttribute('data-x')) + circle.radius,
				y: parseFloat(circleEl.getAttribute('data-y')) + circle.radius
			};

			const eventStartPos = { x: event.clientX, y: event.clientY };

			function dragStart() {
				document.addEventListener('mousemove', dragged);
				document.addEventListener('mouseup', dragEnd);
			}

			function dragged(event) {
				const currentPos = { x: event.clientX, y: event.clientY };

				const delta = {
					x: currentPos.x - eventStartPos.x,
					y: currentPos.y - eventStartPos.y
				};

				// start dragging if mouse moved DRAG_THRESOLD px
				if (!isDragging &&
					(Math.abs(delta.x) > DRAG_THRESOLD || Math.abs(delta.y) > DRAG_THRESOLD)
				) {
					isDragging = true;
					packer.dragStart(circle.id);
				}

				const newPos = { x: circleStartPos.x + delta.x, y: circleStartPos.y + delta.y };

				if (isDragging) {
					// end dragging if circle is outside the bounds
					if (
						newPos.x < circle.radius || newPos.x > bounds.width - circle.radius ||
						newPos.y < circle.radius || newPos.y > bounds.height - circle.radius
					) {
						dragEnd();
					} else {
						packer.drag(circle.id, newPos);
					}
				}
			}

			function dragEnd() {
				isDragging = false;
				document.removeEventListener('mousemove', dragged);
				packer.dragEnd(circle.id);
			}

			if (!isDragging) {
				dragStart();
			}
		}

		function random(min, max, intResult) {
			if (typeof min !== 'number' && typeof max !== 'number') {
				min = 0;
				max = 1;
			}

			if (typeof max !== 'number') {
				max = min;
				min = 0;
			}

			let result = min + Math.random() * (max - min);

			if (intResult) {
				result = parseInt(result, 10);
			}

			return result;
		}
	</script>
</body>

</html>