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Add a canvas source

Add a canvas source to the map.

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Add a canvas source</title>
    <meta property="og:description" content="Add a canvas source to the map." />
    <meta charset='utf-8'>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel='stylesheet' href='https://unpkg.com/[email protected]/dist/maplibre-gl.css' />
    <script src='https://unpkg.com/[email protected]/dist/maplibre-gl.js'></script>
    <style>
        body { margin: 0; padding: 0; }
        html, body, #map { height: 100%; }
    </style>
</head>
<body>
<canvas id="canvasID" width="400" height="400">Canvas not supported</canvas>
<div id="map"></div>
<script>
    //Animation from https://javascript.tutorials24x7.com/blog/how-to-draw-animated-circles-in-html5-canvas
    const canvas = document.getElementById('canvasID');
    const ctx = canvas.getContext('2d');
    canvas.style.display = 'none';
    const circles = [];
    const radius = 20;

    function Circle(x, y, dx, dy, radius, color) {
        this.x = x;
        this.y = y;
        this.dx = dx;
        this.dy = dy;

        this.radius = radius;

        this.draw = function () {
            ctx.beginPath();
            ctx.arc(this.x, this.y, this.radius, 0, Math.PI * 2, false);
            ctx.strokeStyle = color;
            ctx.stroke();
        };

        this.update = function () {
            if (this.x + this.radius > 400 || this.x - this.radius < 0) {
                this.dx = -this.dx;
            }

            if (this.y + this.radius > 400 || this.y - this.radius < 0) {
                this.dy = -this.dy;
            }

            this.x += this.dx;
            this.y += this.dy;

            this.draw();
        };
    }

    for (let i = 0; i < 5; i++) {
        const color = `#${(0x1000000 + Math.random() * 0xffffff).toString(16).substr(1, 6)}`;
        const x = Math.random() * (400 - radius * 2) + radius;
        const y = Math.random() * (400 - radius * 2) + radius;

        const dx = (Math.random() - 0.5) * 2;
        const dy = (Math.random() - 0.5) * 2;

        circles.push(new Circle(x, y, dx, dy, radius, color));
    }

    function animate() {
        requestAnimationFrame(animate);
        ctx.clearRect(0, 0, 400, 400);

        for (let r = 0; r < 5; r++) {
            circles[r].update();
        }
    }

    animate();

    const map = new maplibregl.Map({
        container: 'map',
        zoom: 5,
        minZoom: 4,
        center: [95.899147, 18.088694],
        style:
            'https://api.maptiler.com/maps/streets/style.json?key=get_your_own_OpIi9ZULNHzrESv6T2vL'
    });

    map.on('load', () => {
        map.addSource('canvas-source', {
            type: 'canvas',
            canvas: 'canvasID',
            coordinates: [
                [91.4461, 21.5006],
                [100.3541, 21.5006],
                [100.3541, 13.9706],
                [91.4461, 13.9706]
            ],
            // Set to true if the canvas source is animated. If the canvas is static, animate should be set to false to improve performance.
            animate: true
        });

        map.addLayer({
            id: 'canvas-layer',
            type: 'raster',
            source: 'canvas-source'
        });
    });
</script>
</body>
</html>