Timeline AS3 collision detection

[German Cutz]

I'm learning AS3. On stage, I have a movie clip mc_1 that responds to keyboarding. There are four movie clips rectangle_mc .. rectangle_mc3 on each side of stage.

PROBLEM:

mc_1 is moved up, down, right, and left with arrow keys. It detects rectangles when hit, but it does not stop when hitting rectangles. How can I make mc_1 stop when hitting a rectangle?


HERE IS MY SCRIPT:

stage.addEventListener(KeyboardEvent.KEY_DOWN, moveDrawing);


function moveDrawing(event:KeyboardEvent): void
{
var speed:uint=5;

switch (event.keyCode){
case Keyboard.RIGHT:
mc_1.x+=speed;
break;

case Keyboard.LEFT:
mc_1.x-=speed;
break;

case Keyboard.UP:
mc_1.y-=speed;
break;


case Keyboard.DOWN:
mc_1.y+=speed;
break;
}
}


// collision detection

mc_1.addEventListener(Event.ENTER_FRAME, rectangleHit);
function rectangleHit(event:Event): void
{
if (mc_1.hitTestObject(rectangle_mc|| rectangle_mc2)){
mc_1.stop(); //HERE IS WHERE I WANT IT STOP.
trace ("rectangle & 2 hit");
}

if (mc_1.hitTestObject(rectangle_mc1|| rectangle_mc3)){
mc_1.stop();//HERE IS WHERE I WANT IT STOP.
trace("rectangle1 &3 hit");
}
};

thanks for your help.


German

[Tilpo]

Hey there German,

I took a look at your code and saw that without changing the idea of your original code it would be a little bit complicated to solve the problem. But i did it anyway:

stage.addEventListener(KeyboardEvent.KEY_DOWN, moveDrawing);

var keyPressed:String;
var keyEnabled:Array = [true, true, true, true];

function moveDrawing(event:KeyboardEvent):void {
    var SPEED:uint = 5;
    switch (event.keyCode) {
        case Keyboard.RIGHT :
            if (keyEnabled[0]) {
                mc_1.x += SPEED;
                keyPressed="right";
                enableAll();
            }
            break;
            
        case Keyboard.LEFT :
            if (keyEnabled[1]) {
                mc_1.x-=SPEED;
                keyPressed="left";
                enableAll();
            }
            break;
            
        case Keyboard.UP :
            if (keyEnabled[2]) {
                mc_1.y-=SPEED;
                keyPressed="up";
                enableAll();
            }
            break;
            
        case Keyboard.DOWN :
            if (keyEnabled[3]) {
                mc_1.y+=SPEED;
                keyPressed="down";
                enableAll();
            }
            break;
    }
    function enableAll():void {
        keyEnabled = [true, true, true, true];
    }
}

mc_1.addEventListener(Event.ENTER_FRAME, rectangleHit);
function rectangleHit(event:Event):void {

    if (mc_1.hitTestObject(rectangle_mc)||mc_1.hitTestObject(rectangle_mc2)) {
        disableKey();
        trace("rectangle & 2 hit");
    }
    if (mc_1.hitTestObject(rectangle_mc1)||mc_1.hitTestObject(rectangle_mc3)) {
        disableKey();
        trace("rectangle1 &3 hit");
    }
    
    function disableKey(key:String = keyPressed):void {
        if (key=="right") {
            keyEnabled[0]=false;
        }
        if (key=="left") {
            keyEnabled[1]=false;
        }
        if (key=="up") {
            keyEnabled[2]=false;
        }
        if (key=="down") {
            keyEnabled[3]=false;
        }
    }
}

What it basically does is that when there is collision with a rectangle, he disables the mc_1 to go any further in the current direction.
When mc_1 collides with a rectangle, the code checks what key was pressed in order to create that collision. Then whenever a key is pressed it checks whether it is not the key that caused the collision, when it that key, he simply ignores the key being pressed. When a different key is pressed the code re enables the disabled key.

[German Cutz]

Dear Tilpo:

Thanks for taking the time to help me. I used your suggestion. However, I haven't been able to make it work yet.

1. It seems there is more code I couldn't get. I got up to case keyBoard.UP
2. Flash reports 1180: Call to a possibly undefined method enabled. when enableAll(); is used.

Can you please resend your code in a way I can see it all?
Why is this error message when using enableAll?

Thanks again.

German