/**
* Copyright tjoen ( http://wonderfl.net/user/tjoen )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/niYZ
*/
package {
import flash.display.BitmapData;
import flash.display.Bitmap;
import flash.display.Sprite;
import flash.geom.ColorTransform;
import flash.filters.ColorMatrixFilter;
import flash.geom.Point;
import flash.events.Event;
import flash.geom.Rectangle;
import flash.display.Shape;
public class ScrollingPerlinNoise extends Sprite {
public var numOctaves:int;
public var skyColor:uint;
public var cloudsHeight:int;
public var cloudsWidth:int;
public var periodX:Number;
public var periodY:Number;
public var scrollAmountX:int;
public var scrollAmountY:int;
public var cloudsBitmapData:BitmapData;
private var cloudsBitmap:Bitmap;
private var cmf:ColorMatrixFilter;
private var colorBackground:Shape;
private var displayWidth:Number;
private var displayHeight:Number;
private var seed:int;
private var sliceDataH:BitmapData;
private var sliceDataV:BitmapData;
private var sliceDataCorner:BitmapData;
private var horizCutRect:Rectangle;
private var vertCutRect:Rectangle;
private var cornerCutRect:Rectangle;
private var horizPastePoint:Point;
private var vertPastePoint:Point;
private var cornerPastePoint:Point;
private var origin:Point;
private var cloudsMask:Shape;
private var grayScale:Boolean;
public function ScrollingPerlinNoise(w:int = 300, h:int = 200, scrollX:int = 0, scrollY:int = -4, useBG:Boolean = true, col:uint = 0x000000, nOctaves:Number = 5, perlinPeriodX:Number = 150, perlinPeriodY:Number = 150, gray:Boolean = true) {
displayWidth = w;
displayHeight = h;
//the code can be modified so that the clouds are bigger than the display
cloudsWidth = displayWidth;
cloudsHeight = displayHeight;
periodX = perlinPeriodX;
periodY = perlinPeriodY;
scrollAmountX = scrollX;
scrollAmountY = scrollY;
grayScale = gray;
numOctaves = nOctaves;
skyColor = col;
cloudsBitmapData = new BitmapData(cloudsWidth,cloudsHeight,true);
cloudsBitmap = new Bitmap(cloudsBitmapData);
origin = new Point(0,0);
if (useBG) {
colorBackground = new Shape();
colorBackground.graphics.beginFill(skyColor);
colorBackground.graphics.drawRect(0,0,displayWidth,displayHeight);
colorBackground.graphics.endFill();
this.addChild(colorBackground);
}
this.addChild(cloudsBitmap);
/*
//use a mask if the clouds are made to be bigger than the display
cloudsMask = new Shape();
cloudsMask.graphics.beginFill(0xFFFFFF);
cloudsMask.graphics.drawRect(0,0,displayWidth,displayHeight);
cloudsMask.graphics.endFill();
this.addChild(cloudsMask);
cloudsBitmap.mask = cloudsMask;
*/
makeClouds();
setRectangles();
}
public function startScroll():void {
this.addEventListener(Event.ENTER_FRAME, onEnter);
}
public function stopScroll():void {
this.removeEventListener(Event.ENTER_FRAME, onEnter);
}
private function setRectangles():void {
if (scrollAmountX != 0) {
sliceDataV = new BitmapData(Math.abs(scrollAmountX), cloudsHeight - Math.abs(scrollAmountY), true);
}
if (scrollAmountY != 0) {
sliceDataH = new BitmapData(cloudsWidth, Math.abs(scrollAmountY), true);
}
if ((scrollAmountX != 0)&&(scrollAmountY != 0)) {
sliceDataCorner = new BitmapData(Math.abs(scrollAmountX), Math.abs(scrollAmountY), true);
}
horizCutRect = new Rectangle(0, cloudsHeight - scrollAmountY, cloudsWidth - Math.abs(scrollAmountX), Math.abs(scrollAmountY));
vertCutRect = new Rectangle(cloudsWidth - scrollAmountX, 0, Math.abs(scrollAmountX), cloudsHeight - Math.abs(scrollAmountY));
cornerCutRect = new Rectangle(cloudsWidth - scrollAmountX, cloudsHeight - scrollAmountY,Math.abs(scrollAmountX), Math.abs(scrollAmountY));
horizPastePoint = new Point(scrollAmountX, 0);
vertPastePoint = new Point(0, scrollAmountY);
cornerPastePoint = new Point(0, 0);
if (scrollAmountX < 0) {
cornerCutRect.x = vertCutRect.x = 0;
cornerPastePoint.x = vertPastePoint.x = cloudsWidth + scrollAmountX;
horizCutRect.x = -scrollAmountX;
horizPastePoint.x = 0;
}
if (scrollAmountY < 0) {
cornerCutRect.y = horizCutRect.y = 0;
cornerPastePoint.y = horizPastePoint.y = cloudsHeight + scrollAmountY;
vertCutRect.y = -scrollAmountY;
vertPastePoint.y = 0;
}
}
public function makeClouds():void {
seed = int(Math.random()*0xFFFFFF);
//draw clouds
if (grayScale) {
cloudsBitmapData.perlinNoise(periodX,periodY,numOctaves,seed,true,true,1,true);
}
else {
cloudsBitmapData.perlinNoise(periodX,periodY,numOctaves,seed,true,true,7,false);
}
//alpha adjust
var alphaAdjust:ColorMatrixFilter = new ColorMatrixFilter([1,0,0,0,0,
0,1,0,0,0,
0,0,1,0,0,
1,0,0,0,0]);
cloudsBitmapData.applyFilter(cloudsBitmapData, cloudsBitmapData.rect, new Point(), alphaAdjust);
}
private function onEnter(evt:Event):void {
cloudsBitmapData.lock();
//copy to buffers the part that will be cut off
if (scrollAmountX != 0) {
sliceDataV.copyPixels(cloudsBitmapData, vertCutRect, origin);
}
if (scrollAmountY != 0) {
sliceDataH.copyPixels(cloudsBitmapData, horizCutRect, origin);
}
if ((scrollAmountX != 0)&&(scrollAmountY != 0)) {
sliceDataCorner.copyPixels(cloudsBitmapData, cornerCutRect, origin);
}
//scroll
cloudsBitmapData.scroll(scrollAmountX, scrollAmountY);
//draw the buffers on the opposite sides
if (scrollAmountX != 0) {
cloudsBitmapData.copyPixels(sliceDataV, sliceDataV.rect, vertPastePoint);
}
if (scrollAmountY != 0) {
cloudsBitmapData.copyPixels(sliceDataH, sliceDataH.rect, horizPastePoint);
}
if ((scrollAmountX != 0)&&(scrollAmountY != 0)) {
cloudsBitmapData.copyPixels(sliceDataCorner, sliceDataCorner.rect, cornerPastePoint);
}
cloudsBitmapData.unlock();
}
}
}
