Working on just having smooth movement of a square in javascript. At the moment it is very choppy and not at all smooth. This is what I am using at the moment:

window.addEventListener('keydown', function(event) {
     if(!dead && playing){
 	switch (event.keyCode) {

 	case 37: 
 	moveLeft = true;
 	break;
 
   	case 38: 
     	moveUp = true;
   	break;

   	case 39: 
   	moveRight = true;
   	break;
 
    	case 40: 
   	moveDown = true;
    	break;
  	}
  	};
	}, false);

     function GameLoop(){

	if(moveLeft){
	x -= 6;
	moveLeft = false;
	}else if(moveUp){
	y -= 6;
	moveUp = false;
	}else if(moveRight){
	x += 6;
	moveRight = false;
	}else if(moveDown){
	y += 6;
	moveDown = false;
	}

     if(playArcade){
        setTimeout(GameLoop, 33);
     }

I read this blog post about on the topic of smooth movement in javascript: http://nokarma.org/2011/02/27/javascript-game-development-keyboard-input/index.html

However, I did not understand a lot of it, although I think it contains the answer to my problem. If some could explain what the blog post says/means to a noob like myself that would be great - or find another solution to my problem.

p.s. I may have missed some of the detail in the code posted above, if some of the variables and other items are missing, its just because I did not post them in this code, they are in the real thing though.

I'm not sure what you mean by smooth movement, but I would remove the move___ = false; statements so that you don't have to keep pressing the buttons over. Once you do this, you would have to add another event listener for 'keyup' and set the move___ = false when that happens. This way, as long as you're holding down a direction, the gameloop will update your position, but as soon as you let go, it will stop. If you do it this way, you can change the 6 to a smaller number like 1 to achieve a less "jumpy" motion.

Also, typically you'd want to keep track of your delta_time in the game loop (how much time has passed since the last run of the loop).

Then to update position, you would add (velocity * delta_time) to your position.

I'm not sure what you mean by smooth movement, but I would remove the move___ = false; statements so that you don't have to keep pressing the buttons over. Once you do this, you would have to add another event listener for 'keyup' and set the move___ = false when that happens. This way, as long as you're holding down a direction, the gameloop will update your position, but as soon as you let go, it will stop. If you do it this way, you can change the 6 to a smaller number like 1 to achieve a less "jumpy" motion.

Also, typically you'd want to keep track of your delta_time in the game loop (how much time has passed since the last run of the loop).

Then to update position, you would add (velocity * delta_time) to your position.

Thank you, I think the solution was just checking when the key had been released. Saved me loads of time, thanks again :) !