Question

My collision code is supposed to inverse the x velocity and reduce it to a third, then when the player is not pressing either “A” or “D” keys, the velocity should slowly reduce to zero, however, once the player collides the velocity only reduces to a small decimal between .25 and .70 (either positive or negative based on previous directions.)

//Function to determine what to do with keys
function KeyHandler():void{
    //A Key Handlers
    if(aKeyPressed == true){
        if(Math.abs(_vx) < MaxSpeed){
            _vx += -6;
        }
    }
    //Player _vx somehow won't hit zero!!!
    else if(aKeyPressed == false){
        if(_vx < 0){
            _vx += 1;
        }
    }
    //D Key Handlers
    if(dKeyPressed == true){
        if(Math.abs(_vx) < MaxSpeed){
            _vx += 6;
        }
    }
    else if(dKeyPressed == false){
        if( _vx > 0){
            _vx += -1;
        }
    }
    //W Key Handlers
    if(wKeyPressed == true){
        if(Jumped == false){
            _vy = -15;
            Jumped = true;
        }
    }
    else if(wKeyPressed == false){

    }
}
//Code for Right Collision
    if(RightCollision){
        while(RightCollision){
            Player.x -= 0.1;
            RightCollision = false;
            if(_boundaries.hitTestPoint((Player.x + (Player.width / 2)), (Player.y - (Player.height / 2)), true)){RightCollision = true;}
        }
        _vx *= -.33
    }
    //Code for Left Collision
    if(LeftCollision){
        while(LeftCollision){
            Player.x += 0.1;
            LeftCollision = false;
            if(_boundaries.hitTestPoint((Player.x - (Player.width / 2)), (Player.y - (Player.height / 2)), true)){LeftCollision = true;}
        }
        _vx *= -.33
    }

Answer 1

Note that abs(-.25) + abs(.7) ~ 1.0

The collision sets the velocity to something that is not an integer (e.g. 2 * .33 ~ .7), so +/- 1 will skip past 0 without landing on it.

The simple fix is to keep the velocity an integer which can be done with Math.floor, for instance. (Account for the difference in +/- velocities: floor only moves numbers one direction.)

Happy coding.

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Also, I am not sure how the int type works in AS3 work, which might be worth exploring.