Knight's Defense: HTML Canvas Game Source Code

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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>Knight's Defense</title>
    <style>
        body {
            margin: 0;
            overflow: hidden;
            background: #222;
            font-family: 'Courier New', Courier, monospace;
            color: white;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            height: 100vh;
        }
        #game-container {
            position: relative;
            border: 4px solid #555;
            box-shadow: 0 0 20px rgba(0,0,0,0.5);
        }
        canvas {
            display: block;
            background: #4a773c; /* Grass color */
        }
        #ui {
            position: absolute;
            top: 10px;
            left: 10px;
            pointer-events: none;
        }
        .health-bar {
            width: 300px;
            height: 20px;
            background: #333;
            border: 2px solid #fff;
        }
        #hp-fill {
            width: 100%;
            height: 100%;
            background: #e74c3c;
            transition: width 0.1s;
        }
        #overlay {
            position: absolute;
            top: 0; left: 0; width: 100%; height: 100%;
            background: rgba(0,0,0,0.7);
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            text-align: center;
            z-index: 10;
        }
        button {
            padding: 10px 20px;
            font-size: 20px;
            cursor: pointer;
            background: #f1c40f;
            border: none;
            font-weight: bold;
        }
    </style>
</head>
<body>

<div id="game-container">
        <canvas id="gameCanvas"></canvas>
        <div id="ui">
            <div>CASTLE HEALTH: <span id="hp-text">10000</span></div>
            <div class="health-bar"><div id="hp-fill"></div></div>
        </div>
        <div id="overlay">
            <h1 id="status-title">KNIGHT'S DEFENSE</h1>
            <p>Defend the castle from the villagers!</p>
            <p>Arrows to Move | Space to Swing Spear</p>
            <button onclick="startGame()">START GAME</button>
        </div>
    </div>

canvas.width = 800;
    canvas.height = 400;

// Game State
    let gameActive = false;
    let castleHealth = 10000;
    let score = 0;
    const villagers = [];
    const keys = {};

// Audio Setup (Procedural Sound)
    const audioCtx = new (window.AudioContext || window.webkitAudioContext)();
    function playSliceSound() {
        const osc = audioCtx.createOscillator();
        const gain = audioCtx.createGain();
        osc.type = 'sawtooth';
        osc.frequency.setValueAtTime(400, audioCtx.currentTime);
        osc.frequency.exponentialRampToValueAtTime(50, audioCtx.currentTime + 0.1);
        gain.gain.setValueAtTime(0.1, audioCtx.currentTime);
        gain.gain.exponentialRampToValueAtTime(0.01, audioCtx.currentTime + 0.1);
        osc.connect(gain);
        gain.connect(audioCtx.destination);
        osc.start();
        osc.stop(audioCtx.currentTime + 0.1);
    }

// Knight Object
    const knight = {
        x: 150,
        y: 200,
        w: 40,
        h: 40,
        speed: 4,
        attacking: false,
        attackTimer: 0,
        dir: 1 // 1 for right, -1 for left
    };

// Input Listeners
    window.addEventListener('keydown', e => {
        keys[e.code] = true;
        if (e.code === 'Space' && !knight.attacking) {
            knight.attacking = true;
            knight.attackTimer = 15;
            playSliceSound();
        }
    });
    window.addEventListener('keyup', e => keys[e.code] = false);

function spawnVillager() {
        if (!gameActive) return;
        villagers.push({
            x: canvas.width + 50,
            y: Math.random() * (canvas.height - 60) + 30,
            w: 30,
            h: 30,
            speed: 1.5 + Math.random() * 1.5
        });
        setTimeout(spawnVillager, Math.max(500, 2000 - (score * 10)));
    }

function update() {
        if (!gameActive) return;

// Move Knight
        if (keys['ArrowUp'] && knight.y > 0) knight.y -= knight.speed;
        if (keys['ArrowDown'] && knight.y < canvas.height - knight.h) knight.y += knight.speed;
        if (keys['ArrowLeft'] && knight.x > 100) { knight.x -= knight.speed; knight.dir = -1; }
        if (keys['ArrowRight'] && knight.x < canvas.width - 40) { knight.x += knight.speed; knight.dir = 1; }

// Attack Logic
        if (knight.attacking) {
            knight.attackTimer--;
            if (knight.attackTimer <= 0) knight.attacking = false;
        }

// Update Villagers
        for (let i = villagers.length - 1; i >= 0; i--) {
            const v = villagers[i];
            v.x -= v.speed;

// Damage Castle
            if (v.x < 80) {
                castleHealth -= 100;
                villagers.splice(i, 1);
                continue;
            }

// Hit by Spear
            if (knight.attacking) {
                const spearX = knight.x + (knight.dir === 1 ? knight.w : -40);
                const dist = Math.hypot((knight.x + knight.w/2 + (knight.dir * 40)) - (v.x + v.w/2), (knight.y + knight.h/2) - (v.y + v.h/2));
                if (dist < 60) {
                    villagers.splice(i, 1);
                    score++;
                    continue;
                }
            }
        }

// Check Game Over
        if (castleHealth <= 0) {
            castleHealth = 0;
            gameOver();
        }

hpText.innerText = castleHealth;
        hpFill.style.width = (castleHealth / 10000 * 100) + "%";
    }

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

// Draw Castle (Behind)
        ctx.fillStyle = '#7f8c8d';
        ctx.fillRect(0, 0, 80, canvas.height);
        ctx.fillStyle = '#95a5a6';
        for(let i=0; i<canvas.height; i+=40) ctx.fillRect(60, i, 30, 20);

// Draw Village (Background/Front)
        ctx.fillStyle = '#5d4037';
        ctx.fillRect(700, 50, 60, 40); // Simple house
        ctx.fillRect(720, 250, 50, 50);

// Draw Knight
        ctx.fillStyle = '#bdc3c7'; // Armor
        ctx.fillRect(knight.x, knight.y, knight.w, knight.h);
        ctx.fillStyle = '#34495e'; // Helmet visor
        ctx.fillRect(knight.x + (knight.dir === 1 ? 25 : 5), knight.y + 10, 10, 5);

// Draw Spear
        if (knight.attacking) {
            ctx.strokeStyle = '#ecf0f1';
            ctx.lineWidth = 4;
            ctx.beginPath();
            ctx.moveTo(knight.x + knight.w/2, knight.y + knight.h/2);
            ctx.lineTo(knight.x + knight.w/2 + (knight.dir * 70), knight.y + knight.h/2 + (Math.sin(knight.attackTimer) * 20));
            ctx.stroke();
        } else {
            ctx.strokeStyle = '#7f8c8d';
            ctx.lineWidth = 3;
            ctx.beginPath();
            ctx.moveTo(knight.x + (knight.dir === 1 ? knight.w : 0), knight.y + knight.h);
            ctx.lineTo(knight.x + (knight.dir === 1 ? knight.w + 10 : -10), knight.y - 10);
            ctx.stroke();
        }

// Draw Villagers
        ctx.fillStyle = '#d35400';
        villagers.forEach(v => {
            ctx.fillRect(v.x, v.y, v.w, v.h);
            ctx.fillStyle = '#000';
            ctx.fillRect(v.x + 5, v.y + 5, 5, 5);
            ctx.fillRect(v.x + 20, v.y + 5, 5, 5);
            ctx.fillStyle = '#d35400';
        });

requestAnimationFrame(() => {
            update();
            draw();
        });
    }

function startGame() {
        if (audioCtx.state === 'suspended') audioCtx.resume();
        overlay.style.display = 'none';
        castleHealth = 10000;
        score = 0;
        villagers.length = 0;
        gameActive = true;
        spawnVillager();
    }

function gameOver() {
        gameActive = false;
        overlay.style.display = 'flex';
        statusTitle.innerText = "THE CASTLE HAS FALLEN!";
        document.querySelector('button').innerText = "TRY AGAIN";
    }

draw();
</script>
</body>
</html>

Knight's Defense: HTML Canvas Game Source Code

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