スプライン曲線とパーリンノイズの波
スプライン曲線を描くには４つの点が必要で両端の2点は、補助になっているみたい。
そして残りの2点間の途中の座標を求めて直線を細かく描いていくみたい。
/**
* Copyright gaziya ( http://wonderfl.net/user/gaziya )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/ykKm
*/
package {
import flash.display.Sprite;
import flash.geom.ColorTransform;
import flash.display.Shape;
import flash.display.Bitmap;
import flash.geom.Point;
import flash.display.BitmapData;
import flash.events.Event;
public class FlashTest extends Sprite {
public function FlashTest() {
var bitmapData:BitmapData=new BitmapData(stage.stageWidth,stage.stageHeight,false,0x0)
addChild(new Bitmap(bitmapData))
var noise:BitmapData = new BitmapData(30,30)
addChild(new Bitmap(noise))
var shape:Shape = new Shape
var spline:Function = function(p:Vector.<Point>, t:Number):Point {
var point:Point = new Point
for each(var v:String in ["x","y"]){
point[v] = 0.5*(
(2*p[1][v]) +
(-p[0][v] + p[2][v]) * t +
(2*p[0][v] - 5*p[1][v] + 4*p[2][v] - p[3][v]) * Math.pow(t,2) +
(-p[0][v] + 3*p[1][v]- 3*p[2][v] + p[3][v]) * Math.pow(t,3) )
}
return point
}
var val:Number = 0
var colorTransform:ColorTransform = new ColorTransform(0.9,0.9,0.9)
addEventListener(Event.ENTER_FRAME, function(e:Event):void {
bitmapData.colorTransform(bitmapData.rect, colorTransform)
val += 0.2
noise.perlinNoise(20,10,2,100,false,true,7,true,[new Point(val,0)])
shape.graphics.clear()
shape.graphics.lineStyle(1, 0x2255ff)
for (var i:int = 0; i < noise.height; i++) {
var points:Vector.<Point> = new Vector.<Point>
shape.graphics.moveTo(-10,250)
for (var j:int = 0; j < noise.width; j++) {
var value:Number = noise.getPixel(j, i) % 0x100
points.push(new Point(j*20-20, value*2))
if (points.length>3) {
var split:int = 5
for (var k:int = 0; k < split; k++) {
var point:Point = spline(points, k/split)
shape.graphics.lineTo(point.x, point.y)
}
points.shift()
}
}
}
bitmapData.draw(shape)
})
}
}
}