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karlo4208
08.10.2022, 17:01
was ist hier falsch gelaufen?
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Rocket vs Aliens</title>
  <style>
    canvas {
      background-color: gray;
    }
    
  </style>
  <script>
    let KEY_SPACE = false;
    let KEY_UP = false;
    let KEY_DOWN = false;
    let canvas;
    let ctx;
    let backgroundImage = new Image();
    let rocket = {
      x: 100,
      y: 200,
      width: 200,
      height: 80,
      src: 'img/rocket.png'
    };
    let spaceship = {
      x: 500,
      y: 200,
      width: 100,
      height: 40,
      src: 'img/spaceship.png'
    };
    document.onkeydown = function(e) {
      if (e.keyCode ==32) { // Leertaste gedrückt
        KEY_SPACE = true;
      }
      if (e.keyCode ==32) { // unten gedrückt
        KEY_SPACE = true;
      }
    
      if (e.keyCode ==38) { // Oben gedrückt
        KEY_UP = true;
      }
    }
    document.onkeyup = function(e) {
      if (e.keyCode ==32) { // Leertaste losgelassen
        KEY_SPACE = false;
      }
    
      if (e.keyCode ==38) { // oben losgelassen
        KEY_UP = false;
      }
      if (e.keyCode ==40) { // unten losgelassen
        KEY_DOWN = false;
      }
    }
    function startGame () {
      canvas = document.getElementById('canvas');
       ctx = canvas.getContext('2d');
      loadImages();
      draw();
      // calculate
    }
    function loadImages() {
      backgroundImage.src = 'img/background.png';
      rocket.img = new Image();
      rocket.img.src = rocket.src;
      spaceship.img = new Image();
      spaceship.img.src = spaceship.src;
    }
    function draw() {
      ctx.drawImage(backgroundImage, 0, 0);
      ctx.drawImage(rocket.img, rocket.x, rocket.y, rocket.widht, rocket.height);
      
      requestAnimationFrame(draw);
    }
  </script>
</head>
<body onload="startGame()">
<canvas id="canvas" width="720" height="480"></canvas>
</body>
</html>
HTML, Webseite, CSS, JavaScript, HTML5, Programmiersprache, Webentwicklung
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