How to re-position the children of a MovieClip? - actionscript-3

I am having a container mc with 5 children mcs.
children names mc0,mc1....mc4.
cont.getChildByName("mc"+Number(cont.numChildren-1)).x =
cont.getChildByName("mc0").x - 20 *1.2;
after this re-position process.. I want to set the last item position as 0 and so on. How can I do this?
My target is to attain a circular movement.
like
[mc0][mc1][mc2]
[mc2][mc0][mc1]
[mc1][mc2][mc0]
[mc0][mc1][mc2]

//Of course, you don't necessarily have to create absolute positions,
//this is a simple example...
var positions:Array = [{x:0,y:0} , {x:20, y:20} etc....];
var children:Array = [mc0 , mc1 ... mcN];
//Provided that positions & children have the same length
private function rotate():void
{
//remove the last element of the Array
var lastChild:MovieClip = children.pop();
//Add it to the beginning of the Array
children.unshift(lastChild );
//Assign new positions
//Here you could tween for smoother effect
for( var i:int ; i < positions.length ; ++i )
{
children[i].x = positions[i].x;
children[i].y = positions[i].y;
}
}

Let's introduce an offset variable simulating the rotation's progression:
var offset:uint = 0;
Now we must define each clip's position depending on this variable. I will introduce a gap constant for the distance between two items.
const GAP:uint = 20;
for (var iMc:int=0; iMc < cont.numChildren; iMc++)
{
mc = cont.getChildByName("mc" + iMc.toString()) as Sprite;
mc.x = GAP * ((iMc + offset) % cont.numChildren);
}
The % operator (modulo) allows you to get a number between 0 and the second operand-1

Related

How to define rectangle of visible children in Flash/AS3 ("real" element size)

I use BitmapData.draw to make a snapshot of a graph canvas. On the canvas located some children in random positions (including negative positions). I should to define in some way what rectangle bounds to shoot.
SO, for example, i have 3 nodes in the view (canvas):
{10x10, (-5; -3)}
{20x20, (0; 0)}
{30x30, (40; 40)}
In this case bounds should be (-5; -3) (left top) to (70; 70) (right bottom).
Is there a way to define "real" element size, based on its children layout?
May be some methods from Flex framework?
DisplayObject.getBounds() and DisplayObject.getRect() are the methods that you are looking for.
Both methods
[Return] a rectangle that defines the boundary of the display object, based on the coordinate system defined by the targetCoordinateSpace parameter
The difference between them is:
The getBounds() method is similar to the getRect() method; however, the Rectangle returned by the getBounds() method includes any strokes on shapes, whereas the Rectangle returned by the getRect() method does not.
If you use strokes, you probably want to use getBounds()
Looks like in the most cases getBounds() and getRect() should work, but some times they may have problem calculating right-bottom corner, for instance, when component explicitly resized.
For my component I found already implemented method (this solution also ignores invisible children!):
public function calcDisplayObjecBoundingBox():Rectangle
{
var numChildren:int = this.numChildren;
var result:Rectangle = new Rectangle( 0, 0, 0, 0 );
var i:int = 0;
var child:DisplayObject;
if( numChildren > 0 )
{
//find first visible child and initialize rectangle bounds
for( i = 0; i < numChildren; i++ )
{
child = this.getChildAt( i );
if( child.visible )
{
result.left = child.x;
result.top = child.y;
result.right = child.x + child.width;
result.bottom = child.y + child.height;
i++;
break;
}
}
for( ; i < numChildren; i++ )
{
child = this.getChildAt( i );
if( child.visible )
{
result.left = Math.min( result.left, child.x );
result.right = Math.max( result.right, child.x + child.width );
result.top = Math.min( result.top, child.y )
result.bottom = Math.max( result.bottom, child.y + child.height );
}
}
}
Probably, it works pretty much the same as for getBounds() and getRect(), but calculates right-bottom point by children, not the component itself.

How to place multiple bitmaps in a scrollable rectangle? AS3

This code builds a palette of tiles for use in a map maker program. It takes in an array set by its parent and uses the bitmaps(from the objects) in that array to display a grid of tiles. Right now it only does a 5x5 grid, but what if there are more than 25 tiles in my tileSet? I want to display only the 5x5 tile grid, but be able to scroll through the images. I imagine that I need to make another rectangle to use as its mask and use a ScrollBar to make it scrollRect, but I can't get this working. Please Help.
public function Palette(X:uint, Y:uint, tileSet:Array)
{
addChild(handleGraphics);
var palette:Rectangle = new Rectangle(X, Y, 5*32, tileSet.length*32); //Default size is 5x5 tiles.
handleGraphics.DrawGrid(32,palette.x,palette.y,5,5);
var counter:int = 0;
for(var i:int = 0; i < 5; i++)
{
paletteArray[i] = [];
for(var u:int = 0; u < 5; u++)
{
if(counter >= tileSet.length)
{
counter = 0; //Which frame to show?
}
var b:Bitmap = new Bitmap(tileSet[counter].Graphic);
b.x = (palette.x) + 32 * u; //Align with palette Rectangle.
b.y = (palette.y) + 32 * i; ///////////////////////////////
addChild(b);
var tileObj:Object = new Object();
tileObj.Name = tileSet[counter].Name;
tileObj.Frame = tileSet[counter].Frame;
tileObj.Graphic = tileSet[counter].Graphic;
paletteArray[i].push(tileObj);
setChildIndex(b, 0); //Under grid.
counter++;
}
}
ActivatePaletteListeners();
}
This code works great for a tileSet array that has less than 25 objects. It loops and shows them continuously until it hits 25. I could do without this I guess, but it is a neat affect.
In another class (HandleTiles) I cycle through my tileSet MovieClip and use each frame to create a new object for each tile.
public function GetPaletteTiles(MC:MovieClip)
{
if (tileArray != null)
{
tileArray.length = 0;
}
for(var i:int = 1; i <= MC.totalFrames; i++)
{
MC.gotoAndStop(i); //Change frame for new info.
var tileObj:Object = new Object(); //The object to push to an array of tiles.
var graphicData:BitmapData = new BitmapData(32,32);
graphicData.draw(MC); //Graphic data from sampleTS.
tileObj.Name = MC.currentFrameLabel;
tileObj.Frame = MC.currentFrame;
tileObj.Graphic = graphicData;
tileArray.push(tileObj);
}
BuildIndexArray(15, 20); //Default size 15 x 20.
}
And here I set the tileSet to use
private function ChangeActiveTileset(Mc:MovieClip)
{
activeTileset = Mc;
GetPaletteTiles(activeTileset);
UpdatePalette();
}
I can change the tileSet with a comboBox. That's why I tear down the tileArray every time I call GetPaletteTiles(). Each tileSet is a different MovieClip, like Buildings, Samples, InTheCity, etc.
Sorry I didn't have time to get this code together earlier. Here's tiling code pieces. Because you're using rectangle and you have to stay under max dimensions you have to move the source mc. I think you already know everything else in there.
// set the bmp dimensions to device screensize to prevent exceeding device's max bmp dimensions
if (bStagePortrait) {
iTileWidth = Capabilities.screenResolutionX;
iTileHeight = Capabilities.screenResolutionY;
} else {
iTileWidth = Capabilities.screenResolutionY;
iTileHeight = Capabilities.screenResolutionX;
}
// mcList.mcListVector is the source mc - a regular mc containing mcs, jpgs, dynamic text, vector shapes, etc.
// mcList.mcListBmp is an empty mc
aListTiles = new Array();
iNumberOfTiles = Math.ceil(mcList.height / iTileHeight);
for (i = 0; i < iNumberOfTiles; i++) {
var bmpTile: Bitmap;
// move the source mc
mcList.mcListVector.y = -(i * iTileHeight);
bmpTile = fDrawTile(mcList, 0, 0, iTileWidth, iTileHeight);
mcList.mcListBmp.addChild(bmpTile);
bmpTile.x = 0;
bmpTile.y = (i * iTileHeight);
aListTiles.push(bmpTile);
}
// remove the regular mc
mcList.mcListVector.removeChild(mcList.mcListVector.mcPic);
mcList.mcListVector.mcPic = null;
mcList.removeChild(mcList.mcListVector);
mcList.mcListVector = null;
}
function fDrawTile(pClip: MovieClip, pX: int, pY: int, pWidth: int, pHeight: int): Bitmap {
trace("fDrawTile: " + pX + "," + pY + " " + pWidth + "," + pHeight);
var rectTemp: Rectangle = new Rectangle(pX, pY, pWidth, pHeight);
var bdClip: BitmapData = new BitmapData(pWidth, pHeight, true, 0x00000000);
var bdTemp: BitmapData = new BitmapData(pWidth, pHeight, true, 0x00000000);
bdClip.draw(pClip, null, null, null, rectTemp, true);
bdTemp.copyPixels(bdClip, rectTemp, new Point(0, 0));
var bmpReturn: Bitmap = new Bitmap(bdTemp, "auto", true);
return bmpReturn;
}

Fit array of movieclips in a fixed box in AS3

I have this array of movieclips (there can be only one but there can also be like 100) and a big movieclip on the stage with a fixed width and height (it can't be resized).
var boxWidth:int = 500
var boxHeight:int = 300
var box:MovieClip = new Movieclip;
box.graphics.beginFill(0x444444);
box.graphics.drawRect(
0,
0,
boxWidth,
boxHeight
);
box.graphics.endFill();
addChild(box);
var movieClipsArray:Array = []; //dynamic number of movieclips
var movieClipsSpacing:int = 10;
for(var i:String in movieClipsArray){
//calculate x, y, width, and height
box.addChild(movieClipsArray[i]);
}
How can I add all the movieclips from the array to the box, while fullfilling the following requirements?
The movieclips may be resized, but they have to keep their height/width ratio
The movieclips may not overlap
The movieclips may not exceed the borders of the box movieclip
There has to be some space between the movieclips (let's say, 10px)
The space of the box movieclip has to be used as efficiently as possible
The movieclips don't have to be in the same order, e.g movieClipsArray[0] could be at the left top, but also in the right bottom or somewhere in the center
I'm sorry for not having done much myself, but I just don't have any idea where to start
Dunno if I'm over complicating this at all, but I'd personally do something like this:
var boxWidth:int = 500;
var boxHeight:int = 300;
// each column and row of equally sized movieclip would be 5/7 and 3/7 of the width/height of the box respectively.
mcColumns = ((movieClipsArray.length / 7) * 5); // tells you how many columns
mcRows = ((movieClipsArray.length / 7) * 3); // tells you how many rows
//calculate width
var availableWidth = boxWidth - (mcColumns * 10); //width available after 10px spaces
var mcWidth:int = availableWidth / mcColumns; //width of each box
//calculate height
var availableHeight = boxHeight - (mcRows * 10); //height available after 10px spaces
var mcHeight:int = availableHeight / mcRows; //height of each box
for(var i:int = 0; i<mcColums; i++;){
for(var j:int = 0; i<mcRows; i++;){
//calculate x
movieClipsArray[i+j].width = mcWidth;
movieClipsArray[i+j].x = (availableWidth / mcWidth) * i;
movieClipsArray[i+j].x += 10 * i; //adds the space
//calculate y
movieClipsArray[i+j].height = mcHeight;
movieClipsArray[i+j].y = (availableHeight /mcWidth) * j;
movieClipsArray[i+j].y += 10 * j; //adds the space
box.addChild(movieClipsArray[i+j]);
}
}
Please bear in mind that I haven't checked this, I just wrote it to help set you on the right track.

How to have an object hover back and forth constrained within a specific radius?

I have a sprite in a movie symbol that I would like to hover back and forth within a 360 radius. I was hoping to make it smooth and random. Never really venturing from its original xy cordinates.
I've tried to create some stipulations with if statements and a starting momentum. Like this:
var num = 2;
stage.addEventListener(Event.ENTER_FRAME, hover);
function hover(evt:Event):void{
//start it moving
cloudWhite.y += num;
cloudWhite.x += num;
//declare these variables
var cX = cloudWhite.x;
var cY = cloudWhite.y;
// object travels 10 pixels
var cXP = cX + 10;
var cXN = cX - 10;
var cYP = cY + 10;
var cYN = cY - 10;
// if object goes 10 pixels reverse direction of momentum (maybe)
if (cX >= cXP) {
num = -2;
}
if (cX <= cXN){
num = 2;
}
if (cY >= cYP) {
num = 2;
}
if (cY <= cYN){
num = 2;
}
Clearly this is super wrong because when it runs the object just either goes to 0,0 or to some place that only the math gods know of.
I am clearly a noob at this kind of math so i apologize but I am very excited to learn the trig behind this.
Thank you for your help and thank you for reading.
You are setting all your variables inside the ENTER_FRAME loop, so none of your conditions ever evaluates to true. On every single frame you are doing this:
cloudWhite.x += 2;
cX = cloudWhite.x;
cXP = cX + 10; // Must == cloudWhite's previous x + 10 + 2;
cXN = cX - 10; // Must == cloudWite's previous x -10 + 2;
if(cX > cXP)... // Can never be true.
if(cX < cXN)... // Can never be true.
What you need to do is:
1) Store the original position of cloudWhite somewhere outside the loop, and store it before the loop begins.
2) Define your bounds relative to the original position of cloudWhite, again before your loop begins. Also define the amount you are going to change the position with each iteration.
3) Start your loop.
4) Increment the current position of cloudWhite on each iteration. Add a little random in here if you want the shape to move in a random manner.
5) Check if the new position of cW is outside your bounds and adjust the direction if it is.
The sample below is crude and jerky but I don't know exactly what effect you're looking for. If you want smoother, longer movements in each direction, consider using the Tween class or a Tween library such as the popular Greensock one, instead of incrementing / decrementing the position manually. There's a useful discussion of this here: http://www.actionscript.org/forums/archive/index.php3/t-163836.html
import flash.display.MovieClip;
import flash.events.Event;
// Set up your variables
var original_x:Number = 100; // Original x
var original_y:Number = 100; // Original y
var x_inc:Number = 5; // X Movement
var y_inc:Number = 5; // Y Movenent
var bounds:Number = 50; // Distance from origin allowed
// Doesn't take into account width of object so is distance to nearest point.
// Create an MC to show the bounds:
var display:MovieClip = addChild(new MovieClip()) as MovieClip;
display.graphics.lineStyle(1, 0x0000FF);
display.graphics.beginFill(0x0000FF, 0.5);
display.graphics.drawRect(0-bounds, 0-bounds, bounds * 2, bounds *2);
display.x = original_x;
display.y = original_y;
addChild(display);
// Create our moving mc:
var mc:MovieClip = addChild(new MovieClip()) as MovieClip;
mc.graphics.beginFill(0xFF0000, 1);
mc.graphics.drawCircle(-10, -10, 20);
// Position it:
mc.x = original_x;
mc.y = original_y;
addChild(mc);
// Loop:
function iterate($e:Event = null):void
{
// Move the mc by a random amount related to x/y inc
mc.x += (Math.random() * (2 * x_inc))/2;
mc.y += (Math.random() * (2 * y_inc))/2;
// If the distance from the origin is greater than bounds:
if((Math.abs(mc.x - original_x)) > bounds)
{
// Reverse the direction of travel:
x_inc == 5 ? x_inc = -5 : x_inc = 5;
}
// Ditto on the y axis:
if((Math.abs(mc.y - original_y)) > bounds)
{
y_inc == 5 ? y_inc = -5 : y_inc = 5;
}
}
// Start the loop:
addEventListener(Event.ENTER_FRAME, iterate);
This should get you started. I'm sure there are any number of other ways to do this with formal trig, but this has the benefit of being very simple, and just an extension of your existing method.

AS3: Random Point on Irregular Shape

I have a MovieClip holding an irregular shape such as this one:
I need to generate a random point on this shape.
I can use brute force by generating points within the bounding box and then hitTesting to see if they reside on the irregular shape. However, I'm sure there's a more efficient way to tackle this problem.
What is the most efficient way to generate a random point on an irregular shape?
You mentioned hitTest, but I assume you meant hitTestPoint().
If so, a function go get the random points you mention, would look a bit like this:
function getRandomPointsInClip(target:MovieClip,numPoints:int):Vector.<Point>{
var points:Vector.<Point> = new Vector.<Point>(numPoints,true);
var width:Number = target.width,height:Number = target.height;
for(var i:int = 0; i < numPoints ; i++){
var point:Point = new Point(target.x+Math.random() * width,target.y+Math.random() * height);
if(target.hitTestPoint(point.x,point.y,true)) points[i] = point;//is the random coord inside ?
else i = i-1;//nope, go back one step - > retry above until it is inside
}
return points;
}
The other I hinted at in my comment involves looping through non transparent pixels in a bitmap data of your object. This method would insure you don't have many duplicates, as opposed to the previous method, but it also means, you have less control over the number of points created and there's extra memory used for creating the bitmap. Still, for documentation purposes, here is the function:
function getGridPointsInClip(target:MovieClip,res:int,offset:Number = 3):Vector.<Point>{
var points:Vector.<Point> = new Vector.<Point>();
var x:int,y:int,alpha:int,w:int = int(target.width),h:int = int(target.height);
var bmd:BitmapData = new BitmapData(w,h,true,0x00FFFFFF);bmd.draw(target);
var pixels:Vector.<uint> = bmd.getVector(bmd.rect),numPixels:int = w*h;
for(var i:int = 0; i < numPixels; i+=res) {
x = i%bmd.width;
y = int(i/bmd.width);
alpha = pixels[i] >>> 24;
if(alpha > 0) points.push(new Point(x+random(-offset,offset),y+random(-offset,offset)));
}
return points;
}
function random(from:Number,to:Number):Number {
if (from >= to) return from;
var diff:Number = to - from;
return (Math.random()*diff) + from;
}
And here'a very basic test:
var pts:Vector.<Point> = getRandomPointsInClip(mc,300);
//var pts:Vector.<Point> = getGridPointsInClip(mc,100,4);
for(var i:int = 0 ; i < pts.length; i++) drawCircle(pts[i].x,pts[i].y,3,0x009900);
function getRandomPointsInClip(target:MovieClip,numPoints:int):Vector.<Point>{
var points:Vector.<Point> = new Vector.<Point>(numPoints,true);
var width:Number = target.width,height:Number = target.height;
for(var i:int = 0; i < numPoints ; i++){
var point:Point = new Point(target.x+Math.random() * width,target.y+Math.random() * height);
if(target.hitTestPoint(point.x,point.y,true)) points[i] = point;//is the random coord inside ?
else i = i-1;//nope, go back one step - > retry above until it is inside
}
return points;
}
function getGridPointsInClip(target:MovieClip,res:int,offset:Number = 3):Vector.<Point>{
var points:Vector.<Point> = new Vector.<Point>();
var x:int,y:int,alpha:int,w:int = int(target.width),h:int = int(target.height);
var bmd:BitmapData = new BitmapData(w,h,true,0x00FFFFFF);bmd.draw(target);
var pixels:Vector.<uint> = bmd.getVector(bmd.rect),numPixels:int = w*h;
for(var i:int = 0; i < numPixels; i+=res) {
x = i%bmd.width;
y = int(i/bmd.width);
alpha = pixels[i] >>> 24;
if(alpha > 0) points.push(new Point(x+random(-offset,offset),y+random(-offset,offset)));
}
return points;
}
function random(from:Number,to:Number):Number {
if (from >= to) return from;
var diff:Number = to - from;
return (Math.random()*diff) + from;
}
function drawCircle(x:Number,y:Number,radius:Number,color:uint):void{
graphics.lineStyle(1,color);
graphics.drawCircle(x-radius,y-radius,radius);
}
HTH
If you think of some non-blob like shapes, it's clear the check random pixel, try again method isn't really a good way. The bounding box area could be huge compared to the shape area.
What you could do to improve the effectiveness is getting a vector of the BitmapData of the shape. It should contain all pixels of the bounding box. Update - it would be nice now if we could pick a random point, and remove it from the vector if it isn't inside the shape. Unfortunately the vector only contains the pixels' colour, not the position which is implicit and only correct if we don't change the vector's length. Since we don't need to know the actual colour, we can omit all transparent pixels and store an inside pixel's position as it's value in the vector. This way we don't need to create a new object for each pixel of the shape (that would be quite expensive!).
var v:Vector.<uint> shapeBoxBitmap.getVector(shapeBoxBitmap.rect);
var pixelNum:int = v.length;
for(var i:uint = 0; i < pixelNum; i++) {
if( v[i] && 0xFF000000 == 0) { // transparent pixel, outside off shape
v.splice(i,1);
} else {
v[i] = i;
}
}
//get random point
var randomPixel:int = v[Math.floor(Math.random()*v.length)];
var point:Point = new Point(randomPixel%shapeBitmap.width,int(randomPixel/shapeBitmap.width));