Test collision between two movie clips in two different classes AS3 - actionscript-3

I need to test the collision between 2 movie clips, using air for android action script 3.
Its a collision between an object and several obstacles.
My structure is the following :
The base FLA file, is linked to Action Script file called baseCode.as.
In this AS file, i create the obsctacles, using the following code :
baseCode.as :
package {
import flash.display.MovieClip;
import flash.events.Event;
import flash.geom.Point;
import Mc_MC; // Not strictly needed
public class baseCode extends flash.display.MovieClip
{
//private static var SYMBOLS:Array = new Array(MySymbol1, MySymbol2);
public var t:int = 0;
public function baseCode()
{
// Create five symbols:
for (var i:int = 0; i < 5; i++) {
trace(i);
makeSymbol();
}
}
function randomRange(minNum:Number, maxNum:Number):Number
{
return (Math.floor(Math.random() * (maxNum - minNum + 1)) + minNum);
}
public function makeSymbol():void
{
trace("IT entered makeSymbol");
// Pick a random symbol from the array:
// var symType:Class = SYMBOLS[0];
//trace(SYMBOLS[Math.random() * SYMBOLS.length]);
// Construct the new symbol:
//var Positi : Number = new Number(Math.random);
var loc:Point = new Point(randomRange(100,stage.stage.height),0);
var loc2:Point = new Point(randomRange(110,stage.stage.height),0);
//var loc:Point = new Point(10*randomRange(15, stage.width),100*randomRange(10 , stage.width));
trace("this is the starting point" , loc);
var sym:Mc_MC = new Mc_MC(1 + Math.random() *10, loc);
if( t % 2 == 0 ){
var sym2:Mc_MC2 = new Mc_MC2(15 + Math.random() *10, loc);
// Listen for the object hitting the left edge:
//sym2.addEventListener(Event.COMPLETE, remakeObject);
this.addChild(sym2);
}
sym.addEventListener(Event.COMPLETE, remakeObject);
this.addChild(sym);
t ++;
}
public function remakeObject(e:Event):void
{
e.target.removeEventListener(Event.COMPLETE, remakeObject);
//e.removeChild(sym);
//e.parent.removeChild(this.child);
// removeChild(this);
// this.removeChild(sym);
// Replace the dead symbol:
makeSymbol();
}
}
}
Mc_MC and Mc_MC2 are two Action Script file in which the obstacles are called :
Mc_MC.as :
package {
import flash.display.MovieClip;
import flash.events.Event;
import flash.geom.*;
import flash.display.Screen;
import flash.system.Capabilities;
public class Mc_MC extends MovieClip
{
public var speed:Number; // Pixels moved per frame
var valuee:baseCode;
public function Mc_MC(speed:Number, startPosition:Point)
{
this.speed = speed;
this.addEventListener(Event.ENTER_FRAME, update);
this.x = startPosition.x;
this.y = startPosition.y;
}
public function update(speed:Number)
{
var screenWidth:Number = Capabilities.screenResolutionX;
var screenHeight:Number = Capabilities.screenResolutionY;
trace("this.y" , this.y);
trace("this is the stage height" , screenHeight);
trace("this.speed" , this.speed);
if (this.y >= screenHeight - 100) { // We're at the left edge
trace("Entered if");
trace("new Starting Pos" , this.y);
this.y = stage.height;
parent.removeChild(this);
this.removeEventListener(Event.ENTER_FRAME, update);
this.dispatchEvent(new Event(Event.COMPLETE));
}
else this.y += this.speed;
}
}
}
In the base FLA file, i create the main object that will collide with all the obstacles created using Mc_MC and Mc_MC2. I create it using the following code :
Home.fla
import flash.events.*
//import flash.events.EventDispatcher.addEventListener()
import flash.display.DisplayObject;
//import flash.events.MouseEvent;
import flashx.textLayout.events.UpdateCompleteEvent;
import flash.display.MovieClip;
var offsetX:Number;
var offsetY:Number;
//var draggedObject:DisplayObject;
var my_obj:OriginalObject = new OriginalObject();
//left.addEventListener(MouseEvent.MOUSE_MOVE, drag);
//The speed of the scroll movement.
var scrollSpeed:uint = 2;
//This adds two instances of the movie clip onto the stage.
var s1:ScrollBg = new ScrollBg();
var s2:ScrollBg = new ScrollBg();
left.addEventListener(MouseEvent.MOUSE_DOWN,mouseDown);
function mouseDown(e:MouseEvent):void {
stage.addEventListener(MouseEvent.MOUSE_UP,mouseUp); //listen for mouse up on the stage, in case the finger/mouse moved off of the button accidentally when they release.
addEventListener(Event.ENTER_FRAME,myButtonClick); //while the mouse is down, run the tick function once every frame as per the project frame rate
}
function mouseUp(e:MouseEvent):void {
removeEventListener(Event.ENTER_FRAME,myButtonClick); //stop running the tick function every frame now that the mouse is up
stage.removeEventListener(MouseEvent.MOUSE_UP,mouseUp); //remove the listener for mouse up
}
right.addEventListener(MouseEvent.MOUSE_DOWN,mouseDown2);
function mouseDown2(e:MouseEvent):void {
stage.addEventListener(MouseEvent.MOUSE_UP,mouseUp2); //listen for mouse up on the stage, in case the finger/mouse moved off of the button accidentally when they release.
addEventListener(Event.ENTER_FRAME,stopDragging); //while the mouse is down, run the tick function once every frame as per the project frame rate
}
function mouseUp2(e:MouseEvent):void {
removeEventListener(Event.ENTER_FRAME,stopDragging); //stop running the tick function every frame now that the mouse is up
stage.removeEventListener(MouseEvent.MOUSE_UP,mouseUp2); //remove the listener for mouse up
}
my_obj.x = stage.width / 2;
my_obj.y = stage.height - (stage.height / 3 );
stage.addChild(my_obj);
function myButtonClick(ev:Event):void
{
trace("UPPP");
if(my_obj.x > (my_obj.width*2)){
my_obj.x = my_obj.x - 10;
trace("In the limit");
}
else {
trace("out of bounds");
}
trace("myButton has been clicked.");
}
//// This function is called when the mouse button is released.
function stopDragging(ev2:Event):void
{
trace("Down");
if(my_obj.x <= right.x){
my_obj.x = my_obj.x + 10;
}
}
How can I test the collision of the moving Mc_MC / Mc_MC2 with my_obj considering that the come from different AS files?
I am new to AS, so any help would be appreciated!

If you want to be able to collision test objects from different classes / parentage, then you need to set up your project in a way that you can gain a reference to said objects.
From the looks of it, your two objects are actually in the same class already (as your main timeline code and document class code share the same scope, so what you declare in one should be available in the other).
The only thing you are missing, is a top-level reference to your obstacle/Mc_MC. As currently you assign it to a var that is scoped to the makeSymbol function (so you only have a reference to it inside that function).
Solution
In your document class (baseCode.as) , create a top-level var to hold a reference to that obstacle: (for reference, you have a top level var called t, put this line above or below that)
private var obstacle:Mc_MC;
later in your function that instantiates the new Mc_MC (makeSymbol), assign the instance to that top level var:
obstacle = new Mc_MC(1 + Math.random() *10, loc);
addChild(obstacle);
Now you can access that obstacle var anywhere else in the main timeline or document class.
if(my_obj.hitTest(obstacle)){
}
As an aside, if you have a document class, there is no point in having code on the first frame of your main timeline as that code would work the same in your document class (though it has to be contained in a function). Here is an example of where to move main timeline code:
public class Main extends MovieClip {
public function Main():void {
//listen for the added to stage event prior to do anything display oriented
this.addEventListener(Event.ADDED_TO_STAGE, init);
}
private function init(e:Event):void {
//this is the best place to put the equivalent of timeline code (not including vars or functions, put those in the class root NOT nested here)
}
}

Related

Flash AS3 Error: 1013: The private attribute may be used only on class property definitions

C:\Users\Lab3project\MainDocument.as, Line 103, Column 7 1013: The
private attribute may be used only on class property definitions.
The lines of code concerned:
package {
//these are flash built-in classes
import flash.display.MovieClip;
import flash.events.TimerEvent;
import flash.utils.Timer;
import flash.events.Event;
//Our own custom class
import MainTimer;
public class MainDocument extends MovieClip{
private var gameTimer:MainTimer;
private var thePlayer:Player;
private var theEnemy:Enemy;
private var maxEnemies: int = 3;
private var e:int = 0;
private var childrenOnStage:int;
public function MainDocument() {
// constructor code
trace("the main document is alive");
// new instance MainTimer class
gameTimer = new MainTimer();
// must add it to the stage
addChild(gameTimer);
//adjust its postion on stage
gameTimer.x = 20;
gameTimer.y = 20;
//add the player
thePlayer = new Player();
addChild(thePlayer);
// adjust its postion on the stage
thePlayer.x = stage.stageWidth * 0.5;
//assign the name property
thePlayer.name = "player";
while(e < maxEnemies){
createEnemy();
e++;
} //end while
//Update this variable every time a child is added to the stage
childrenOnStage = this.numChildren
// Add event listener to control timing of main game loop
addEventListener(Event.ENTER_FRAME,mainGameLoop);
}//end function MainDocument
private function createEnemy():void{
trace("create enemy");
theEnemy = new Enemy();
addChild(theEnemy);
//Place in a random spot on stage
theEnemy.x = (Match.random() * stage.stageWidth);
theEnemy.y = 0;
//assign the name property
theEnemy.name = "enemy";
//Update this variable every time a child is added to the stage
childrenOnStage = this.numChildren
} //end function createEnemy
//the main loop for the game
private function mainGameLoop(event:Event): void{
checkForGameReset();
processCollisions();
scrollStage();
} // end functiom mainGameLoop
private function checkForGameReset():void{
//define conditions
} //end function checkForGameReset
private function processCollisions():void{
//set up the main loop to look through all collidale objects on stage
for(var c:int;c < childOnStage;c++){
//trace ("Child on stage c= " + c +
//test for a player of enemy child on stage
if (getChildAt(c).name == "player" || getChildAt(c).name == "enemy"){
//see if object is touching the game stage
if( theGameStage.hitTestPoint(getChildAt(c).x, getChildAt(c).y,true)){
//while it is still touching the game stage
while( theGameStage.hitTestPoint(getChildAt(c).x, getChildAt(c).y,true)==true){
//called from CollisionObject class,so force the connection
CollisionObject(getChildAt(c)).incrementUpward();
if( theGameStage.hitTestPoint(getChildAt(c).x, getChildAt(c).y,true)==false){
}CollisionObject(getChildAt(c)).keepOnBoundary(); //make it stick
} // end if
} // end while
} //end if touching
} //end if player or enemy
} //end for loop
} //end function processCollisions
The lines of code concerned: is here where im getting the error
private function scrollStage(): void
{
// figure out logic
}
// end function scrollStage
//add the enemy for testing
theEnemy = new Enemy();
addChild(theEnemy);
// adjust its postion on the stage
theEnemy.x = stage.stageWidth * 0.5;
theEnemy.y = 200;
} // end public function MainDocument
} // end public class
} // end package
After I have change that code ,it then says I have a extra character at the end but the characters I have to have at the end.
Problems like this often occur because of a slight typo in syntax. Perhaps you have accidentally declared your private function within another function?
public function doSomething() {
//a whole bunch of stuff
//then we forget to close the function with a brace "}"
private function scrollStage() {
//but we're still defining doSomething! Throw error!
}
Go and look for errors like this, and hopefully you can find the problem.

ActionScript 3, handling MOUSE_UP outside stage

I'm new to ActionScript 3.0. I tried a tutorial at http://www.senocular.com/flash/tutorials/as3withmxmlc/ . The demo program animates a ball and allows it to be dragged.
There was a problem with the program as written. When you drag the mouse outside the stage and release the mouse button, the ball wouldn't get the MOUSE_UP event. The code, therefore would never call stopDrag(). I searched stackoverflow for suggestions, and one suggestion was to listen to MOUSE_UP with the stage as well as the ball and add some logic for dealing with it.
I added some code to do this. I also refactored the program as written because it was pretty disorganized. Here's what I have now:
package {
import flash.display.Sprite;
import flash.events.Event;
import flash.events.MouseEvent;
import flash.geom.Point;
import flash.geom.Rectangle;
public class BallToss extends Sprite {
private var ball:TossableBall;
// mouse position at last call to trackMouseMvt()
private var lastMousePos:Point = new Point();
// delta mouse movement from frame L-1 to frame L, where L is last frame
private var lastDeltaMouse:Point = new Point();
public function BallToss() {
var stageBounds:Rectangle = new Rectangle(0, 0, stage.stageWidth,
stage.stageHeight);
ball = new TossableBall(50, stageBounds);
ball.x = stageBounds.width/2;
ball.y = stageBounds.height/2;
addChild(ball);
ball.addEventListener(MouseEvent.MOUSE_DOWN, grabBall);
// however I order the next two calls to addEventListener(), it seems
// that the ball's MOUSE_UP gets handled before the stage's MOUSE_UP
stage.addEventListener(MouseEvent.MOUSE_UP, handleStageMouseUp);
ball.addEventListener(MouseEvent.MOUSE_UP, releaseBall);
// initialize 'lastMousePos' and set up 'trackMouseMvt' to be called on
// every frame
lastMousePos = new Point(mouseX, mouseY);
ball.addEventListener(Event.ENTER_FRAME, trackMouseMvt);
}
private function grabBall(evt:MouseEvent):void {
trace("in grabBall");
// set ball 'glideVector' to (0,0) so it will stop moving
ball.setGlideVector(new Point(0,0));
ball.startDrag();
}
private function releaseBall(evt:MouseEvent):void {
trace("in releaseBall");
ball.stopDrag();
// set up the ball to glide at the rate of 'lastDeltaMouse'
ball.setGlideVector(lastDeltaMouse);
}
private function trackMouseMvt(evt:Event):void {
var currMouse:Point = new Point(mouseX, mouseY);
lastDeltaMouse = currMouse.subtract(lastMousePos);
lastMousePos = currMouse;
}
private function handleStageMouseUp(evt:Event):void {
trace("in handleStageMouseUp");
ball.stopDrag();
var stageBounds:Rectangle = new Rectangle(0, 0, stage.stageWidth,
stage.stageHeight);
if (ball.x > stageBounds.right - 0.5)
ball.x = stageBounds.right - 0.5;
else if (ball.x < 0)
ball.x = 0;
if (ball.y > stageBounds.bottom - 0.5)
ball.y = stageBounds.bottom - 0.5;
else if (ball.y < 0)
ball.y = 0;
}
}
}
import flash.display.Sprite;
import flash.events.Event;
import flash.geom.Point;
import flash.geom.Rectangle;
class TossableBall extends Sprite {
private var stageBounds:Rectangle;
private var glideVector:Point = new Point();
private var friction:Number = .95;
public function TossableBall(size:Number, stageBoundsIn:Rectangle) {
stageBounds = stageBoundsIn;
graphics.lineStyle(1);
graphics.beginFill(0xFF8000);
graphics.drawCircle(0, 0, size/2);
addEventListener(Event.ENTER_FRAME, glide);
}
public function setGlideVector(glideVectorIn:Point):void {
glideVector = glideVectorIn;
}
private function glide(evt:Event):void {
x += glideVector.x;
y += glideVector.y;
var shapeBounds:Rectangle = getBounds(parent);
if (shapeBounds.left < stageBounds.left) {
glideVector.x = Math.abs(glideVector.x);
} else if (shapeBounds.right > stageBounds.right) {
glideVector.x = -Math.abs(glideVector.x);
}
if (shapeBounds.top < stageBounds.top) {
glideVector.y = Math.abs(glideVector.y);
} else if (shapeBounds.bottom > stageBounds.bottom) {
glideVector.y = -Math.abs(glideVector.y);
}
glideVector.x *= friction;
glideVector.y *= friction;
}
}
I don't like this code very much. The problem comes down to not being able to detect all the cases in one place. I would like to write something like this:
if (..ball and stage both got MOUSE_UP..) {
..handle it..;
else if (..only stage got MOUSE_UP..) {
..handle it..;
}
This logic would let me write more foolproof, simpler case handling and clearer logic. As things stand, there is a lot of complex behavior that emerges from this way of organizing the code.
The event listening model doesn't seem to make this possible. The response to events must happen individually, or must it? Is there a way to detect events that are "in the queue"?
Alternatively, I could avoid using startDrag(), i.e. avoid making the ball Sprite draggable, and have only the stage listen to MOUSE_UP, then handle all the drag logic myself. That would also let me better handle questions like where I want the ball to be positioned when the user drags outside the stage. I wonder if that is better overall.
To track object being dragged this works good for me:
ball.addEventListener(MouseEvent.MOUSE_DOWN, onBallMouseDown)
var _stage:Stage;
private function onBallMouseDown(e:MouseEvent):void
{
_stage = stage;
stage.addEventListener(MouseEvent.MOUSE_UP, onStageMouseUp)
stage.addEventListener(MouseEvent.MOUSE_MOVE, onStageMouseMove)
ball.startDrag();
}
private function onStageMouseMove(e:MouseEvent):void
{
// track ball coordinates
}
private function onStageMouseUp(e:MouseEvent):void
{
ball.stopDrag();
_stage.removeEventListener(MouseEvent.MOUSE_UP, onStageMouseUp)
_stage.removeEventListener(MouseEvent.MOUSE_MOVE, onStageMouseMove)
}
What about that, after years of Flash programming only now have I discovered the joys of MouseEvent.RELEASE_OUTSIDE. No more ugly hacks needed.

AS3 - If symbol's coordinates arrive here?

I'm using Flash Professional CS5.5 and I need to make an app where there is a ball (symbol) that moves using the accelerometer and I want that, when the ball coordinates A reach this coordinates B it goes to frame 2 (gotoAndPlay(2)). I have to find the ball coord first, right? How do I make this?
Here is the code I've now
c_ball.addEventListener(MouseEvent.MOUSE_DOWN, fl_ClickToDrag);
function fl_ClickToDrag(event:MouseEvent):void{
c_ball.startDrag();}
stage.addEventListener(MouseEvent.MOUSE_UP, fl_ReleaseToDrop);
function fl_ReleaseToDrop(event:MouseEvent):void{
c_ball.stopDrag();}
would it work if, after retriving the coordinates?
function f_level (e) if (c_ball.x==100 && c_ball.y==100) {
gotoAndStop(2);}
MOUSE_UP and MOUSE_DOWN are not what you need if you're looking for Accelerometer data. You want the Accelerometer class and associated events.
Try something like this:
import flash.sensors.Accelerometer;
import flash.events.AccelerometerEvent;
var accel:Accelerometer = new Accelerometer();
accel.addEventListener(AccelerometerEvent.UPDATE, handleAccelUpdate);
Update handler:
function handleAccelUpdate(e:AccelerometerEvent):void{
//inside this function you now have access to acceleration x/y/z data
trace("x: " + e.accelerationX);
trace("y: " + e.accelerationY);
trace("z: " + e.accelerationZ);
//using this you can move your MC in the correct direction
c_ball.x -= (e.accelerationX * 10); //using 10 as a speed multiplier, play around with this number for different rates of speed
c_ball.y += (e.accelerationY * 10); //same idea here but note the += instead of -=
//you can now check the x/y of your c_ball mc
if(c_ball.x == 100 && c_ball.y == 100){
trace("you win!"); //fires when c_ball is at 100, 100
}
}
Now this will let you "roll" your MC off the screen so you're probably going to want to add some kind of bounds checking.
Check out this great writeup for more info:
http://www.republicofcode.com/tutorials/flash/as3accelerometer/
An easy and save way is to use colission detection, instead of testing for exectly one position ( what is hard to meet for users) you go for a target area :
package
{
import flash.display.Sprite;
import flash.events.Event;
import flash.events.MouseEvent;
public class Hittester extends Sprite
{
var ball:Sprite = new Sprite();
var testarea:Sprite = new Sprite();
public function Hittester()
{
super();
ball.graphics.beginFill(0xff0000);
ball.graphics.drawCircle(0,0,10);
testarea.graphics.beginFill(0x00ff00);
testarea.graphics.drawRect(0,0,50,50);
testarea.x = 100;
testarea.y = 100;
// if testarea should be invisble
/*testarea.alpha = 0;
testarea.mouseEnabled = false;
*/
ball.addEventListener(MouseEvent.MOUSE_DOWN, startDragging);
addChild(testarea);
addChild(ball);
}
private function startDragging( E:Event = null):void{
ball.startDrag();
stage.addEventListener(MouseEvent.MOUSE_UP, stopDragging);
}
private function stopDragging( E:Event = null):void{
stage.removeEventListener(MouseEvent.MOUSE_UP, stopDragging);
ball.stopDrag();
test();
}
private function test():void{
if( ! ball.hitTestObject(testarea) ){
ball.x = 10;
ball.y = 10;
}
else{
// here goes next frame command ;)
}
}
}
}

A loop in enterframe?

I'm animating a bunch of words in AS3. Because I'm going to be using this on a mobile device, I want to use bitmaps rather than Sprites. So I've created WordObjects, which have a .bitmap property that I can access.
I have the following code, which fires on the click event and loops through an array inside an enterframe event. This is probably a bad idea, but I'm not sure how to do it better. (What is surprising is that it runs just fine in Flashbuilder, but slows to a crawl in Flash CS5.)
Is there some better way to do this? I just want an efficient way to animate the array of bitmaps.
private function clickhandler (e:MouseEvent){
this.addEventListener(Event.ENTER_FRAME, blowemup);
}
private function blowemup(e:Event){
var newPosition:Number;
for(var i:int=0; i<arrWordObjects.length; i++)
{
newPosition = updatePosition(arrWordObjects[i].bitmap);
arrWordObjects[i].bitmap.x += newPosition;
arrWordObjects[i].bitmap.y += getRandomNumber();
}
}
Something that will make a huge difference is using for each(Object in Array) rather than the standard for loop.
private function blowemup(e:Event):void
{
var newPosition:Number;
var i:ArrWordsObjectClass; // <-- don't know what the class for this is, just replace
for each(i in arrWordObjects)
{
newPosition = updatePosition(i.bitmap);
i.bitmap.x += newPosition;
i.bitmap.y += getRandomNumber();
}
}
A for each loop is typed, meaning a lot of time is saved where normally it'd be trying to work out what arrWordObjects[i] is every iteration.
Also, side note: using one ENTER_FRAME driven function and looping through everything in your application that you want to handle each frame is much more efficient than applying hundreds of listeners for objects.
I normally create a handler class that contains the ENTER_FRAME and an array storing my objects, like so:
package
{
import flash.events.Event;
import flash.display.Sprite;
public class Handler extends Sprite
{
// vars
public var elements:Array = [];
/**
* Constructor
*/
public function Handler()
{
addEventListener(Event.ENTER_FRAME, _handle);
}
/**
* Called on each dispatch of Event.ENTER_FRAME
*/
private function _handle(e:Event):void
{
var i:Element;
for each(i in elements)
{
i.step();
}
}
}
}
Then I create a base class for all the objects that I want to handle, containing the step() function called above.
package
{
import flash.display.DisplayObject;
public class Element extends Object
{
// vars
public var skin:DisplayObject;
/**
* Called on each dispatch of Event.ENTER_FRAME at Handler
*/
public function step():void
{
// override me
}
}
}
Now just extend Element with your objects:
package
{
import flash.display.Sprite;
public class MyThing extends Element
{
/**
* Constructor
*/
public function MyThing()
{
skin = new Sprite();
skin.graphics.beginFill(0);
skin.graphics.drawCircle(0,0,40);
skin.graphics.endFill();
}
/**
* Override step
*/
override public function step():void
{
skin.x += 4;
}
}
}
And get it all going!:
var handler:Handler = new Handler();
var m:MyThing;
var i:uint = 0;
for(i; i<10; i++)
{
m = new MyThing();
m.y = Math.random()*stage.stageHeight;
handler.elements.push(m);
addChild(m.skin);
}
How many bitmaps do you plan to have on the stage at a time?
I have had 40 900x16px bitmaps animating on the stage at full speed running on my iphone using air 2.6.
I used a foreach loop in an enterframe event which i added on mouseclick and removed once the animation was finished.
Remember to compile it for the mobile with gpu rendering enabled. (gpu in your app.xml if you are using air 2.6)
This is worth a read too, it explains a lot about performance for mobile devices
http://help.adobe.com/en_US/as3/mobile/WS901d38e593cd1bac-3d719af412b2b394529-8000.html
Here is a basic example of what I had...
package
{
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.Sprite;
import flash.display.StageAlign;
import flash.display.StageScaleMode;
import flash.events.Event;
import flash.events.MouseEvent;
import flash.geom.Rectangle;
[SWF(frameRate="30", backgroundColor="#FF00FF")]
public class Test extends Sprite
{
private var fields:Vector.<Bitmap> = new Vector.<Bitmap>();
public function Test()
{
this.stage.scaleMode = StageScaleMode.NO_SCALE;
this.stage.align = StageAlign.TOP_LEFT;
for(var i:int = 0; i< 37; i++){
var bd:BitmapData = new BitmapData(960, 16, true, 0x000000);
bd.fillRect(new Rectangle(0, 0, 900, 16), Math.round( Math.random()*0xFFFFFFFF ));
var b:Bitmap = new Bitmap(bd);
b.x = 0;
b.y = i*16;
stage.addChild(b);
fields.push(b);
}
stage.addEventListener(MouseEvent.MOUSE_DOWN, onMouseDown);
}
private var inertia:Boolean = false;
private var yCurrent:Number;
private var ySpeed:Number;
private var startY:Number;
private var cy:Number = 0;
private function onEnterFrame(e:Event):void{
if(!inertia){
ySpeed = (startY - yCurrent) ; // / 16;
startY = yCurrent
} else {
ySpeed *= 0.8;
if(ySpeed < 0.01 && ySpeed > -0.01){
inertia = false;
stage.removeEventListener(Event.ENTER_FRAME, onEnterFrame);
}
}
cy += ySpeed;
if(cy > 640)
cy -= 640;
var ty:Number = cy;
for each(var tf:Bitmap in fields){
tf.y = ty;
ty += 16;
if(ty > 640)
ty -= 640;
}
}
private function onMouseDown(e:MouseEvent):void{
inertia = false;
startY = e.stageY;
yCurrent = e.stageY;
stage.addEventListener(Event.ENTER_FRAME, onEnterFrame);
stage.addEventListener(MouseEvent.MOUSE_MOVE, onMouseMove);
stage.addEventListener(MouseEvent.MOUSE_UP, onMouseUp);
}
private function onMouseMove(e:MouseEvent):void{
yCurrent = e.stageY;
}
private function onMouseUp(e:Event):void{
inertia = true;
stage.removeEventListener(MouseEvent.MOUSE_MOVE, onMouseMove);
stage.removeEventListener(MouseEvent.MOUSE_UP, onMouseUp);
}
}
}
I would suggest looking at writing a custom effect on Adobe's website over registering for ENTER_FRAME event. What you've put up there means this code will forever run as long as the program is running. If you wanted to stop the effect or run for 10 frames and stop then you'll have to write more code. It gets even more complex if you want to apply this to several instances. You're going to have to resolve problems that custom effects framework solves.
I'd read how to write custom effects here:
http://livedocs.adobe.com/flex/3/html/help.html?content=createeffects_1.html

How can I use Action Script 3.0 to make random placed Symbols fly by?

I'm trying to make a simple animation with Flash CS4 and Action Script 3.0 to make a number of Symbols fly by from right to left constantly. What I want is that once a symbol has reached the end of the screen it is destroyed and another one is placed at the start position.
I intend to give each symbol a random speed and create a random symbol each time one is 'destroyed'. Any clues where I can start?
As you seem new to flash as a platform I would think writing classes shouldn't be your first port of call when learning ActionScript. Definitely just play about on the timeline for now and learn the basics. As very simple solution to this, I would suggest creating a MovieClip in the library with a class name like 'MyBall'... then paste this onto the first frame of the main timeline et voila.
// Create some variables to store data
var numberOfBalls : int = 20;
var myBalls : Array = [];
var xVelocities : Array = [];
var maxXVelocitySpeed : Number = 5;
var minXVelocitySpeed : Number = 2;
// Add your orginal balls to the stage
for (var i : int = 0; i < numberOfBalls; i++)
{
var myBall : MyBall = new MyBall();
myBall.x = -(Math.random() * stage.stageWidth);
myBall.y = Math.random() * stage.stageHeight;
var xVelocity : Number = minXVelocitySpeed + (Math.random() * (maxXVelocitySpeed - minXVelocitySpeed));
myBalls.push(myBall);
xVelocities.push(xVelocity);
addChild(myBall);
}
// Add a listener for enter frame events
addEventListener(Event.ENTER_FRAME, enterFrameHandler);
//Run this code on every frame to move the balls and reposition them if they are off the stage
function enterFrameHandler(event : Event) : void
{
for each( var myBall : MyBall in myBalls)
{
var ballIndex : int = myBalls.indexOf(myBall);
myBall.x += xVelocity[ballIndex];
if (myBall.x > stage.stageWidth)
{
myBall.x = -(Math.random() * stage.stageWidth);
myBall.y = Math.random() * stage.stageHeight;
}
}
}
First, turn your symbols into MovieClips. Then create a base class MySymbol.as for your symbols, something like:
package {
import flash.display.MovieClip;
import flash.events.Event;
import flash.geom.Point;
public class MySymbol extends MovieClip
{
public var speed:Number; // Pixels moved per frame
public function MySymbol(speed:Number, startPosition:Point)
{
this.speed = speed;
this.addEventListener(Event.ENTER_FRAME, update);
this.x = startPosition.x;
this.y = startPosition.y;
}
private function update():void
{
this.x -= this.speed;
if (this.x < 0 - this.width) { // We're at the left edge
this.removeEventListener(Event.ENTER_FRAME, update);
this.dispatchEvent(new Event(Event.COMPLETE));
}
}
}
}
Then make sure your movie clips are exported for AS3 (the "linkage" option on the item in the library). Make the class name for each item unique (e.g. MySymbol1, MySymbol2), and set the base class to MySymbol.
Your document class might look something like this:
package {
import flash.display.MovieClip;
import flash.events.Event;
import MySymbol; // Not strictly needed
public class DocumentClass extends flash.display.MovieClip
{
private static var SYMBOLS:Array = new Array(MySymbol1, MySymbol2);
public function DocumentClass()
{
// Create five symbols:
for (var i:int = 0; i < 5; i++) {
makeSymbol();
}
}
private function makeSymbol():void
{
// Pick a random symbol from the array:
var symType:Class = SYMBOLS[Math.random() * SYMBOLS.length];
// Construct the new symbol:
var loc:Point = new Point(stage.stageWidth, Math.random() * stage.stageHeight);
var sym:MySymbol = new symType(1 + Math.random() * 30, loc);
// Listen for the object hitting the left edge:
sym.addEventListener(Event.COMPLETE, remakeObject);
this.addChild(sym);
}
private function remakeObject(e:Event):void
{
e.target.removeEventListener(Event.COMPLETE, remakeObject);
this.removeChild(e.target);
// Replace the dead symbol:
makeSymbol();
}
}
}
It is a lot more efficient if instead of destroying and re-creating an object that flies off-stage you re-use the existing one and move it back to the right. But this is an optimization you can implement later, if things become slow.
Note that all the code above is UNTESTED and I have not coded AS3 in a while, so there's likely at least a few bugs in it. Hopefully it will serve as a good enough starting point.
Define a Circle (symbol) class that extends Sprite/Shape and has a velocity variable
Draw a circle (or whatever) with a random color
Math.floor(Math.random() * 0xffffff)
Assign a random value to velocity
minVelocity + Math.floor(Math.random() * velocityRange)
Create a start() method inside the Circle class that registers an enter frame handler
Increment this.y inside the enter frame handler, and dispatch a 'recycleMe' event if y is more than the max value.
Create N instances of Circle, addChild them, and call their start() methods.
listen to 'recycleMe' events on each of them, and reset the value of y from the handler.
Here's a few prompts to get you started.
MovieClips have an x and y property. If you were to add to these numbers over time you would see the MovieClip move along the x and/or y axis of the stage. Look into doing this using the Event.ENTER_FRAME which will allow you to change the values every time the screen is going to update.
Your stage will have a given width (a stageWidth property). You probably want to monitor when your MovieClip's x property is greater than the width of your stage. If it is remove (removeChild) it and add a new one (addChild) and place it back at the start x/y position.