write-monkey/test.html at main · anochj/write-monkey · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Drawing App with Apple Pencil Support</title>
    <style>
        canvas {
            border: 1px solid #000;
            touch-action: none;
        }
    </style>
</head>
<body>
    <h1>Drawing App with Apple Pencil Support</h1>
    <canvas id="drawingCanvas" width="500" height="500"></canvas>
    <br>
    <button id="clearButton">Clear Canvas</button>

    <script>
        const canvas = document.getElementById('drawingCanvas');
        const ctx = canvas.getContext('2d');
        const clearButton = document.getElementById('clearButton');

        let isDrawing = false;
        let lastX = 0;
        let lastY = 0;

        function startDrawing(e) {
            isDrawing = true;
            [lastX, lastY] = getCoordinates(e);
        }

        function draw(e) {
            if (!isDrawing) return;
            const [x, y] = getCoordinates(e);
            ctx.beginPath();
            ctx.moveTo(lastX, lastY);
            ctx.lineTo(x, y);
            ctx.stroke();
            [lastX, lastY] = [x, y];
        }

        function stopDrawing() {
            isDrawing = false;
        }

        function getCoordinates(e) {
            let x, y;
            if (e.type.includes('mouse')) {
                x = e.offsetX;
                y = e.offsetY;
            } else {
                const rect = canvas.getBoundingClientRect();
                x = e.touches ? e.touches[0].clientX - rect.left : e.clientX - rect.left;
                y = e.touches ? e.touches[0].clientY - rect.top : e.clientY - rect.top;
            }
            return [x, y];
        }

        function clearCanvas() {
            ctx.clearRect(0, 0, canvas.width, canvas.height);
        }

        // Mouse events
        canvas.addEventListener('mousedown', startDrawing);
        canvas.addEventListener('mousemove', draw);
        canvas.addEventListener('mouseup', stopDrawing);
        canvas.addEventListener('mouseout', stopDrawing);

        // Touch events (for Apple Pencil and touch devices)
        canvas.addEventListener('touchstart', startDrawing);
        canvas.addEventListener('touchmove', draw);
        canvas.addEventListener('touchend', stopDrawing);

        // Pointer events (for better precision with stylus)
        canvas.addEventListener('pointerdown', startDrawing);
        canvas.addEventListener('pointermove', draw);
        canvas.addEventListener('pointerup', stopDrawing);
        canvas.addEventListener('pointerout', stopDrawing);

        clearButton.addEventListener('click', clearCanvas);

        // Prevent scrolling when touching the canvas
        document.body.addEventListener('touchstart', function (e) {
            if (e.target == canvas) {
                e.preventDefault();
            }
        }, { passive: false });
        document.body.addEventListener('touchend', function (e) {
            if (e.target == canvas) {
                e.preventDefault();
            }
        }, { passive: false });
        document.body.addEventListener('touchmove', function (e) {
            if (e.target == canvas) {
                e.preventDefault();
            }
        }, { passive: false });
    </script>
</body>
</html>