Get Graphics Data from world map sprite and add random spots to the land mass.

Task: Randomly drop dots onto the land mass of a world map sprite.

How to do it:
Transform Sprite into BitmapData and check color values of randomly selected pixel, also check surrounding area for dots too close.

// get object from library

private var worldland:WorldLand = new WorldLand();
private var landpixels:BitmapData;
// make bitmap out of sprite
function makeBitmapData():void { 
 landpixels = new BitmapData(worldland.width, worldland.height);
 landpixels.draw(worldland);
}

// define dotPoints in order to keep track of space taken by previous dots
private var dotPoints:Array = new Array();

// burp function checks random coordinate on map
function burp():void {
 var point:Point = randPos();
 while(isWater(point))point=randPos();
 //trace("found land: " + point.x + "x" + point.y);
 var randomDot:Dot = new Dot();
 randomDot.x = point.x;
 randomDot.y = point.y;

addChild(randomDot);
 dotPoints.push(point);
}
function randPos():Point {
 return new Point(Math.floor(Math.random()*worldland.width), Math.floor(Math.random()*worldland.height));
}

//this means 60 pixels around point are to be kept free  
private var pxrange:uint = 30;

function isWater(p:Point):Boolean {

//first check if spot and surrounding area is already used
 for(var h:uint = 0; h < dotPoints.length; h++){
  var op:Point = dotPoints[h];
  if(op.x > p.x-pxrange&&op.x x+pxrange){
   if(op.y > p.y-pxrange&&op.y < p.y+pxrange){
    //trace("found dot inside point range");
    return true;
   }
  }
 }
 var blue:uint = landpixels.getPixel32(p.x, p.y) & 0xFF;

// in my sprite actually the land mass is blue so if
// the pixel contains blue, this means no, it's not water if(blue.toString(16)=="cc"){
  return false;
 }else{
  return true;
 }
}