Move Link in 4 Directions

[Hurdarr]

Greetings all. For educational purposes, I'm trying to clone The Legend of Zelda (NES) Link's movement.

This what I have:

stop();

var leftKeyDown:Boolean = false;
var upKeyDown:Boolean = false;
var rightKeyDown:Boolean = false;
var downKeyDown: Boolean = false;

var linkSpeed:Number= 7;

// Link Movement

Link.addEventListener(Event.ENTER_FRAME, moveLink);

function moveLink(event:Event):void
{
    if(leftKeyDown)
    {
        Link.x -= linkSpeed;
    }
    
    if(rightKeyDown)
    {
        Link.x += linkSpeed;
    }
    
    if(upKeyDown)
    {
        Link.y -= linkSpeed;
    }
    
    if(downKeyDown)
    {
        Link.y += linkSpeed;
    }
}

// Keys are pressed

stage.addEventListener(KeyboardEvent.KEY_DOWN, checkKeysDown);

function checkKeysDown(event:KeyboardEvent):void
{
    if(event.keyCode == 37)
    {
        leftKeyDown = true;
    }
    
    if(event.keyCode == 38)
    {
        upKeyDown = true;
    }
    
    if(event.keyCode == 39)
    {
        rightKeyDown = true;
    }
    
    if(event.keyCode == 40)
    {
        downKeyDown = true;
    }
}

// Keys are loose

stage.addEventListener(KeyboardEvent.KEY_UP, checkKeysUp);

function checkKeysUp(event:KeyboardEvent):void
{
    if(event.keyCode == 37)
    {
        leftKeyDown = false;
    }
    
    if(event.keyCode == 38)
    {
        upKeyDown = false;
    }
    
    if(event.keyCode == 39)
    {
        rightKeyDown = false;
    }
    
    if(event.keyCode == 40)
    {
        downKeyDown = false;
    }
} 

Link can move in eight directions, what do I need to remove his diagonal movements?

Thanks.

[5TonsOfFlax]

Respond only to the last pressed direction key. So in checkKeysDown, set all your flags to false before your conditionals. By the way, you should be able to use a switch statement to clear up some of those ugly if statements.

[Hurdarr]

Yap, that did the trick. Thanks.

[5TonsOfFlax]

function checkKeysDown(event:KeyboardEvent):void
{
  leftKeyDown = false;
  rightKeyDown = false;
  upKeyDown = false;
  downKeyDown = false;
  switch (event.keyCode) {
    case 37:
        leftKeyDown = true;
        break;
    
    case 38:
        upKeyDown = true;
        break;

    case 39:
        rightKeyDown = true;
        break;
    
    case 40:
        downKeyDown = true;
        break;
}

Be sure to put the "break"s in there, otherwise the execution will "fall-through" from one case to the next.

[Hurdarr]

Hmm..I didn't do that.

function checkKeysDown(event:KeyboardEvent):void
{
    // I added the following lines
    leftKeyDown = false;
    upKeyDown = false;
    rightKeyDown = false;
    downKeyDown = false;
    
    if(event.keyCode == 37)
    {
        leftKeyDown = true;
    }
    
    if(event.keyCode == 38)
    {
        upKeyDown = true;
    }
    
    if(event.keyCode == 39)
    {
        rightKeyDown = true;
    }
    
    if(event.keyCode == 40)
    {
        downKeyDown = true;
    }
} 

Everything seems working fine. But thanks anyway. I'll learn more about switches later.

Also, how can I animate the sprite? I already have the Link animated sprites.

I created one movieclip, and inside of said movieclip, I created four frames. Each one has a movement animation (up,left,down and right). The frames are properly labeled.

However, when I add "Link.gotoAndPlay("left");" to the code and publish the file, it just shows the first frame of the animation when I press the left key.

Do I need to place all the individual non-animated sprites in the movieclip timeline?

Thanks.

[5TonsOfFlax]

Try gotoAndStop rather than gotoAndPlay.

[Hurdarr]

Tried but didn't work.

It might be easier to just upload the .fla.

Thanks for the help.

[Alluvian]

I think your problem is that you are checking your movement logic every frame. So EVERY FRAME you are telling link to go to the first frame of his movement animation.

You need to add 1 boolean variable for each direction link can animate in. Then you do something like the following when your moveright button is pressed:
if (link.movingRight == false) {
link.gotoAndStop("moveRight");
link.movingRight = true;
}

then you need also set that variable to false when you release the button (as well as going to link's stationary frame/animation.

:edit:
actually, you can probably get by with just one variable link.moving depending on how you want to handle concurrent button presses. Pressing right, holding it down and pressing left.

[Hurdarr]

Thanks for the help. That's a little bit too advanced to me, for now.

[Hurdarr]

Hmm...but still didn't solve the animation thingie.

How do you animate a sprite, that has 2 frames per animation? I created 4 movieclips, each doing one of Link's running movement (up, down, left right).

Then I created an empty movieclip with 4 frames. Each frame has one movieclip with one movement direction. They are all labeled.

But I don't know where is the error lies.

I posted the .fla a few posts above.

Thanks.

[Hurdarr]

Still haven't solved the problem.

Help.

[5TonsOfFlax]

I may be misunderstanding your structure, but I think you have two levels of movieclips. The first goes to a frame which corresponds to a direction. The second is a clip on each directional frame which has an animation. You need to use gotoAndStop on the first level and play on the second level. You'll also want to loop the second level clips.

[Hurdarr]

Hmm...and how exactly can I do that? I add the code in the movieclip?

[5TonsOfFlax]

I think you can add the play() command for the inner clip to the frame code of the outer clip.