Computer-Graphics-Lab-Solution/Bresenham_Line_Drawing_Algo.html at main · Its-Shojib/Computer-Graphics-Lab-Solution · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Bresenham Line Drawing Algorithm</title>
    <style>
        canvas {
            border: 1px solid black;
            margin-top: 10px;
        }
    </style>
</head>
<body>
    <canvas id="canvas"></canvas>
    <script>
        window.onload = function() {
            const canvas = document.getElementById('canvas');
            const ctx = canvas.getContext('2d');
            canvas.width = 800;
            canvas.height = 600;

            // Hardcoded start and end points
            const x1 = 50;  // Start X
            const y1 = 50;  // Start Y
            const x2 = 300; // End X
            const y2 = 300; // End Y

            bresenhamLine(ctx, x1, y1, x2, y2);

            function bresenhamLine(ctx, x1, y1, x2, y2) {
                let dx = Math.abs(x2 - x1);
                let dy = -Math.abs(y2 - y1);
                let sx = (x1 < x2) ? 1 : -1;
                let sy = (y1 < y2) ? 1 : -1;
                let err = dx + dy; // error value e_xy
                let e2; // error value doubled

                ctx.beginPath();
                while (true) {
                    ctx.rect(x1, y1, 1, 1); // Set pixel
                    console.log(`Point(${x1}, ${y1})`); // Log points to the console
                    if (x1 === x2 && y1 === y2) break;
                    e2 = 2 * err;
                    if (e2 >= dy) {
                        err += dy;
                        x1 += sx;
                    }
                    if (e2 <= dx) {
                        err += dx;
                        y1 += sy;
                    }
                }

                ctx.fill();
            }
        };
    </script>
</body>
</html>