Transforms are added…endlessly

Question

I\'m creating a simple asteroids-like game in CSS and JS using the DOM over canvas for...experimentation purposes.

My code is pretty small in this example to make i

Answer 1

I think the problem is the detectMovement is calling the checkKeys again and again in infinite loop with same event e.

I tried adding listeners for keyup, keydown, keyleft and keyright so that checkkeys is called only when these keys are pressed.

Please comment if I have understood wrongly

'use strict';

function defineDistances() {
  var distance = {};

  distance.up = -1;
  distance.right = 1;
  distance.down = 1;
  distance.left = -1;
      
  return distance;
}

function defineKeys() {
  var keys = {};

  keys.up = 38;
  keys.right = 39;
  keys.down = 40;
  keys.left = 37;
      
  return keys;
}

function checkKeys( e ) {
e.preventDefault();
  var triBx = document.getElementById( 'v-wrp' ),
      keys = defineKeys(),
      distance = defineDistances();

  switch( e.keyCode ) {
    case keys.up:
      triBx.style.transform += 'translateY(' + distance.up + 'px)';
      break;
    case keys.right:
      triBx.style.transform += 'rotate(' + distance.right + 'deg)';
      break;
    case keys.down:
      triBx.style.transform += 'translateY(' + distance.down + 'px)';
      break;
    case keys.left:
      triBx.style.transform += 'rotate(' + distance.left + 'deg)';
      break;
  }
}

function detectMovement( e ) {
  setInterval ( 
    function() {
      checkKeys( e );
    },
    1000/24
  );  
}

function start() {
  window.addEventListener( 'keydown', checkKeys );
  window.addEventListener( 'keyup', checkKeys );
  window.addEventListener( 'keyright', checkKeys );
  window.addEventListener( 'keyleft', checkKeys );
}

start();

@import url( "https://fonts.googleapis.com/css?family=Nunito" );

html {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100%;
  font-family: "Nunito", sans-serif;
  font-size: 2rem;
}

.v {
  display: block;
  transform: rotate( 180deg );
}

  V