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JavaScript

Konrad Pilch
Konrad Pilch
2,435 Points
Posted by Konrad Pilch
Konrad Pilch
2,435 Points

How to make a flying umm, flying option.

HI,

I want to make flying here.

So if i press up arrow, it will just fly as long as its pressed, and then if i stop it will go down, if i want to press it agian in the air, it will work. Heres what i got:

(function() {
    var requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame || window.webkitRequestAnimationFrame || window.msRequestAnimationFrame;
    window.requestAnimationFrame = requestAnimationFrame;
})();

    var

    canvas = document.getElementById("myCanvas"),
      ctx = canvas.getContext("2d"),
    width = 1900,
    height = 1200,
    player = {
      x : width/2,
      y : height - 5,
      flyY : 3,
      width : 70,
      height : 70,
      speed: 3,
      velX: 6,
      velY: 10,
      fly: 5,
      jumping: false,
      flying: false
    },
    keys = [],
    friction = 0.8,
    gravity = 0.4;

canvas.width = width;
canvas.height = height;

function update(){
  // check keys
 if (keys[32]) {
        //or space
      if(!player.jumping){
       player.jumping = true;
       player.velY = -player.speed*4.4;
      }
    }

    //up arrow
    if (keys[38]) {
      if(!player.flying) {
        player.velY = player.speed-2;
       }
    }

    //down arrow 
  if (keys[40]) { 
        player.velY = +player.speed*2;
    }

    //moving left
    if (keys[37] || keys[30]) {
        player.velX--;
    }

    //moving right
    if (keys[39] || keys[33]) {
        player.velX++;
    }


    player.velX *= friction;

    player.velY += gravity;

    player.x += player.velX;
    player.y += player.velY;

    if (player.x >= width-player.width) {
        player.x = width-player.width;
    } else if (player.x <= 0) {         
        player.x = 0;     
    }    

    if(player.y >= height-player.height){
        player.y = height - player.height;
        player.jumping = false;
    }

      ctx.clearRect(0,0,width,height);
      ctx.fillStyle = "red";
      ctx.fillRect(player.x, player.y, player.width, player.height);

      requestAnimationFrame(update);
}

document.body.addEventListener("keydown", function(e) {
    keys[e.keyCode] = true;
});

document.body.addEventListener("keyup", function(e) {
    keys[e.keyCode] = false;
});

window.addEventListener("load",function(){
    update();
});
Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

Is there some HTML to go with this?

Konrad Pilch
Konrad Pilch
2,435 Points
Konrad Pilch
Konrad Pilch
2,435 Points 
<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title>My Little game</title>

    <script src="myscripts.js"></script>
    <style type="text/css">

        body{
            background: #888;
        }
        canvas{
            background: #222;
        }
    </style>
</head>
<body>

<canvas id="myCanvas"></canvas>

<script src="myscripts.js"></script>

</body>
</html>

Im drawing with canvas.

1 Answer

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

I finally got around to looking at this again (I've been answering several of your other questions meanwhile!).

It looks like you're missing a negative sign on line 45. Here it is corrected:

      player.velY = -player.speed - 2;