Zoom And Pan

import flash.desktop.NativeApplication;
import flash.display.DisplayObject;
import flash.display.DisplayObjectContainer;
import flash.events.Event;
import flash.display.Sprite;
import flash.display.StageAlign;
import flash.display.StageScaleMode;
import flash.events.KeyboardEvent;
import flash.events.MouseEvent;
import flash.geom.Rectangle;
import flash.ui.Keyboard;
import flash.ui.Multitouch;
import flash.ui.MultitouchInputMode;

var DEFAULT_WIDTH:Number;
var DEFAULT_HEIGHT:Number;
var MIN_SCALE:Number = 100;
var MAX_SCALE:Number = 800;
var MOVE_SPEED: Number = 6;
var SIZE_SCALE:Number = 6;
var clickMore: Boolean = false;
var clickLess: Boolean = false;
var clickLeft: Boolean = false;
var clickRight: Boolean = false;
var clickUp: Boolean = false;
var clickDown: Boolean = false;
var clickCenter: Boolean = false;
var keys:Object = {};

/////////////// VERY IMPORTANT ///////////
stage.scaleMode = StageScaleMode.NO_SCALE;
stage.align = StageAlign.TOP_LEFT;
/////////////////////////////////////////





addChild(myMCimg);

//Set default width and height for the object so when clicking CENTER button it will default to that.
DEFAULT_WIDTH = myMCimg.width;
DEFAULT_HEIGHT = myMCimg.height;

//Alignment constants
var Align:Object = {
    CENTER: "center",
   LEFT: "left",
   RIGHT:  "right",
    TOP:"top",
    BOTTOM: "bottom",
    CURRENT_PIVOT: {}
}

var Scaling:Object = {
UP: "up",
DOWN: "down",
scale: function($obj:Object, $scaling:String, $percentage:Number):Object{
$percentage = $percentage/100;
var width:Number = $obj.width * $percentage;
var height:Number =  $obj.height * $percentage;
var scalingWidth:Number = $scaling == Scaling.UP ? + width : - width;
var scalingHeight:Number = $scaling == Scaling.UP ? + height : - height;
  $obj.width += scalingWidth;
  $obj.height += scalingHeight;
  return $obj;
}
}

function resize($obj:DisplayObject, $scaling:String, $percentage:Number, $min:Number=1, $max:Number=3000):void
{
  var size:Object = Scaling.scale({width:$obj.width, height:$obj.height}, $scaling, $percentage);
  if (size.width < $min || size.height < $min) return;
  if (size.width > $max || size.height > $max) return;
  $obj.width = size.width;
  $obj.height = size.height;
}


/* Function for setting the object's registration/pivot/anchor point

Note: Call setPivot() function only ONCE along the code to set the object's
registration/pivot/anchor point to desired position.*/
function setPivot(s:DisplayObjectContainer, alignX:String = "center", alignY:String = "center"):Object{
    Align.CURRENT_PIVOT[s.name] = {x:alignX, y:alignY};
    var obj:Object = {x:s.x, y:s.y};
    var rect:Rectangle = s.getBounds(s);
    var _x:Number;
    var _y:Number;
    if (alignX == Align.CENTER) {
        _x = s.width / 2;
    } else if (alignX == Align.LEFT) {
        _x = 0;
    }
    else if (alignX == Align.RIGHT) {
        _x = s.width;
    }
    if (alignY == Align.CENTER) {
        _y = s.height / 2;
    } else if (alignY == Align.TOP) {
        _y = 0;
    }
    else if (alignY == Align.BOTTOM) {
        _y = s.height;
    }
    var x_offset:Number = _x + rect.x;
    var y_offset:Number = _y + rect.y;
    obj.x -= x_offset;
    obj.y -= y_offset;
    return obj;
}

//Function to center object on stage
function centerImage(image:DisplayObjectContainer):void {
    var x:Number = (stage.fullScreenWidth - image.width)/2;
    var y:Number = (stage.fullScreenHeight - image.height) / 2;
    image.x = x;
    image.y = y;
}

/*Function to show the current registration/pivot/anchor point of the object.
It will appear as a 10x10 blue square. */
function showPivot(image:DisplayObjectContainer):void {
    if (!Align.CURRENT_PIVOT[image.name]) return;
    var spr:Sprite = new Sprite();
    spr.graphics.beginFill(0x0000ff);
    spr.graphics.drawRect(0, 0, 10, 10);
    addChild(spr);
    var x:Number, y:Number;
    var pivotX:String = Align.CURRENT_PIVOT[image.name].x;
    var pivotY:String = Align.CURRENT_PIVOT[image.name].y;

    if (pivotX == Align.CENTER) {
        x = image.x + ((image.width - spr.width)/2);
    }  else if (pivotX == Align.LEFT) {
        x = image.x;
    } else if (pivotX == Align.RIGHT) {
        x = image.x + (image.width - (spr.width));
    }

    if (pivotY == Align.CENTER) {
        y = image.y + ((image.height - spr.height) / 2);
    } else if (pivotY == Align.TOP) {
        y = image.y;
    } else if (pivotY == Align.BOTTOM) {
        y = image.y + (image.height-(spr.height));
    }
    spr.x = x;
    spr.y = y;
}

//INIT

/* Note: Call setPivot() function only ONCE along the code to set the object's
registration/pivot/anchor point to desired position.*/
myMCimg.x = setPivot(myMCimg, Align.LEFT, Align.BOTTOM).x;
myMCimg.y = setPivot(myMCimg, Align.LEFT, Align.BOTTOM).y;

//Center object on stage on when app runs for the first time
centerImage(myMCimg);

//You can uncomment the below function call to show the object's current registration/pivot/anchor point
//showPivot(myMCimg);

// --- Click Zoom more:
btMore.addEventListener(MouseEvent.ROLL_OUT,  stopMoreZoom);
btMore.addEventListener(MouseEvent.MOUSE_DOWN, moreZoom);
function moreZoom(event: MouseEvent): void {
 clickMore = true;
}
btMore.addEventListener(MouseEvent.MOUSE_UP, stopMoreZoom);
function stopMoreZoom(event: MouseEvent): void {
 clickMore = false;
}
// --- Click Zoom less:
btLess.addEventListener(MouseEvent.ROLL_OUT,  stopLessZoom);
btLess.addEventListener(MouseEvent.MOUSE_DOWN, lessZoom);
function lessZoom(event: MouseEvent): void {
 clickLess = true;
}
btLess.addEventListener(MouseEvent.MOUSE_UP, stopLessZoom);
function stopLessZoom(event: MouseEvent): void {
 clickLess = false;
}
// --- Click Move left:
btLeft.addEventListener(MouseEvent.ROLL_OUT, stopLeftMove);
btLeft.addEventListener(MouseEvent.MOUSE_DOWN, leftMove);
function leftMove(event: MouseEvent): void {
 clickLeft = true;
}
btLeft.addEventListener(MouseEvent.MOUSE_UP, stopLeftMove);
function stopLeftMove(event: MouseEvent): void {
 clickLeft = false;
}
// --- Click Move right:
btRight.addEventListener(MouseEvent.ROLL_OUT, stopRightMove);
btRight.addEventListener(MouseEvent.MOUSE_DOWN, rightMove);
function rightMove(event: MouseEvent): void {
 clickRight = true;
}
btRight.addEventListener(MouseEvent.MOUSE_UP, stopRightMove);
function stopRightMove(event: MouseEvent): void {
 clickRight = false;
}
// --- Click Move up:
btUp.addEventListener(MouseEvent.ROLL_OUT, stopUpMove);
btUp.addEventListener(MouseEvent.MOUSE_DOWN, upMove);
function upMove(event: MouseEvent): void {
 clickUp = true;
}
btUp.addEventListener(MouseEvent.MOUSE_UP, stopUpMove);
function stopUpMove(event: MouseEvent): void {
 clickUp = false;
}
// --- Click Move Down:
btDown.addEventListener(MouseEvent.ROLL_OUT, stopDownMove);
btDown.addEventListener(MouseEvent.MOUSE_DOWN, downMove);
function downMove(event: MouseEvent): void {
 clickDown = true;
}
btDown.addEventListener(MouseEvent.MOUSE_UP, stopDownMove);
function stopDownMove(event: MouseEvent): void {
 clickDown = false;
}
// --- Click Move Center:
btCenter.addEventListener(MouseEvent.ROLL_OUT, stopCenterMove);
btCenter.addEventListener(MouseEvent.MOUSE_DOWN, centerMove);
function centerMove(event: MouseEvent): void {
 clickCenter = true;
}
btCenter.addEventListener(MouseEvent.MOUSE_UP, stopCenterMove);
function stopCenterMove(event: MouseEvent): void {
 clickCenter = false;
}


// --- Click Zoom Wheel:

stage.addEventListener(MouseEvent.MOUSE_WHEEL, handleMouseWheel);
function handleMouseWheel(event: MouseEvent): void {
if(event.delta > 0) {
    //Going up
    resize(myMCimg, Scaling.UP, Math.abs(event.delta) * SIZE_SCALE, MIN_SCALE, MAX_SCALE);
} else if(event.delta < 0){
    //Going down
    resize(myMCimg, Scaling.DOWN, Math.abs(event.delta) * SIZE_SCALE, MIN_SCALE, MAX_SCALE);
}
centerImage(myMCimg);
trace("Using the mouse wheel!");
// --- Actions:
}
addEventListener(Event.ENTER_FRAME, enterFrame);
function enterFrame(event: Event): void {
     if (keys[Keyboard.LEFT]) {
 clickLeft = true;

 }
 if (keys[Keyboard.RIGHT]) {
 clickRight = true;
 }
 if (keys[Keyboard.UP]) {
    clickUp = true;
 }
 if (keys[Keyboard.DOWN]) {
  clickDown = true;
 }
 if (keys[Keyboard.ENTER]) {
// --- Centralize:

 clickCenter = true;
 }
 if (clickMore == true) {
  resize(myMCimg, Scaling.UP, SIZE_SCALE, MIN_SCALE, MAX_SCALE);
  centerImage(myMCimg);
 }
 if ((clickLess == true)) {
  resize(myMCimg, Scaling.DOWN, SIZE_SCALE, MIN_SCALE, MAX_SCALE);
  centerImage(myMCimg);
 }
 if (clickLeft == true) {

 myMCimg.x -= MOVE_SPEED;

 }
 if (clickRight == true) {
 myMCimg.x += MOVE_SPEED;
 }
 if (clickUp == true) {
 myMCimg.y -= MOVE_SPEED;
 }
 if (clickDown == true) {
 myMCimg.y += MOVE_SPEED;
 }
 if (clickCenter == true) {
// --- Centralize:

 myMCimg.width = DEFAULT_WIDTH;
 myMCimg.height = DEFAULT_HEIGHT;
 clickCenter = false;
 centerImage(myMCimg);
 }
setChildIndex(myMCimg, 0);
}
// --- Click keys directions keyboard:
stage.addEventListener(KeyboardEvent.KEY_DOWN, pressKeys);
function pressKeys(event:KeyboardEvent): void {
keys[event.keyCode] = true;
}
stage.addEventListener(KeyboardEvent.KEY_UP, releaseKeys);
function releaseKeys(event:KeyboardEvent):void {
    keys[event.keyCode] = false;
}

// --- Click Drag:

 myMCimg.addEventListener(MouseEvent.MOUSE_DOWN, dragMove);
 function dragMove(event: MouseEvent): void {
 myMCimg.startDrag();
}
 myMCimg.addEventListener(MouseEvent.MOUSE_UP, stopDragMove);
 function stopDragMove(event: MouseEvent): void {
 stopDrag();
}