/**
* Copyright phi16 ( http://wonderfl.net/user/phi16 )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/21wz
*/
package {
import flash.display.Sprite;
import flash.events.Event;
import flash.geom.Point;
public class CurveDraw extends Sprite {
public var tx:Number=465/2.0;
public var ty:Number=465/2.0;
public var list:Array=new Array();
public var spr:Sprite=new Sprite();
public var trac:Array=new Array();
public var circ:Sprite=new Sprite();
public var timer:int=0;
public var mn:Array=new Array();
public var i:int=0,ph:int=0;
public function CurveDraw(){
addChild(spr);
for(i=0;i<3;i++){
trac[i]=new Sprite();
trac[i].blendMode="lighten";
addChild(trac[i]);
}
circ.blendMode="lighten";
addChild(circ);
addEventListener(Event.ENTER_FRAME,step);
}
public function step(e:Event):void{
spr.graphics.clear();
circ.graphics.clear();
spr.graphics.beginFill(0);
spr.graphics.drawRect(0,0,465,465);
spr.graphics.endFill();
if(mn.length>0){
spr.graphics.moveTo(mn[0].x,mn[0].y);
for(i=1;i<mn.length;i++){
spr.graphics.lineStyle(8,grayScale(i/600.0));
spr.graphics.lineTo(mn[i].x,mn[i].y);
}
}
for(i=3;i<list.length;i++){
spr.graphics.lineStyle(2,grayScale((i as Number)/list.length));
spr.graphics.drawCircle(list[i].x,list[i].y,5);
}
spr.graphics.lineStyle(2,0xffffff);
if(list.length>0){
spr.graphics.drawCircle(list[list.length-1].x,list[list.length-1].y,5);
}
if(timer%30==0){
list.push(new Point(mouseX,mouseY));
if(list.length>6)list.shift();
ph++;
for(i=0;i<3;i++)drawTrace(i);
timer=0;
}
timer++;
circ.graphics.lineStyle(0);
var cx:Number,cy:Number;
for(i=0;i<3;i++){
trac[i].alpha=(Math.cos((timer-i*30.0+15)/45.0*Math.PI)+1)/2;
cx=spline(list[i].x,list[i+1].x,list[i+2].x,list[i+3].x,timer/30.0+1-i);
cy=spline(list[i].y,list[i+1].y,list[i+2].y,list[i+3].y,timer/30.0+1-i);
circ.graphics.beginFill(0);
circ.graphics.drawCircle(cx,cy,10);
circ.graphics.endFill();
}
for(i=0;i<3;i++){
trac[i].alpha=(Math.cos((timer-i*30.0+15)/45.0*Math.PI)+1)/2;
cx=spline(list[i].x,list[i+1].x,list[i+2].x,list[i+3].x,timer/30.0+1-i);
cy=spline(list[i].y,list[i+1].y,list[i+2].y,list[i+3].y,timer/30.0+1-i);
circ.graphics.lineStyle(4,getColor(ph+i,i==1?1-timer/30.0:0),Math.min(trac[i].alpha*2,1));
circ.graphics.drawCircle(cx,cy,10);
if(i==1)mn.push(new Point(cx,cy));
}
if(mn.length>200)mn.shift();
}
public function drawTrace(i:int):void{
trac[i].graphics.clear();
trac[i].graphics.beginFill(0);
trac[i].graphics.drawRect(0,0,465,465);
trac[i].graphics.endFill();
trac[i].graphics.lineStyle(8,getColor(ph+i,0));
var x0:Number=list[i].x;
var x1:Number=list[i+1].x;
var x2:Number=list[i+2].x;
var x3:Number=list[i+3].x;
var y0:Number=list[i].y;
var y1:Number=list[i+1].y;
var y2:Number=list[i+2].y;
var y3:Number=list[i+3].y;
trac[i].graphics.moveTo(spline(x0,x1,x2,x3,-3),spline(y0,y1,y2,y3,-3));
for(var t:Number=-1.9;t<=3;t+=0.1){
trac[i].graphics.lineTo(spline(x0,x1,x2,x3,t),spline(y0,y1,y2,y3,t));
}
}
public function spline(x0:Number,x1:Number,x2:Number,x3:Number,t:Number):Number{
var v0:Number=(x2-x0)*0.5;
var v1:Number=(x3-x1)*0.5;
return (2*x1-2*x2+v0+v1)*t*t*t+(-3*x1+3*x2-2*v0-v1)*t*t+v0*t+x1;
}
public function getColor(i:Number,br:Number):int{
var colr:int,colg:int,colb:int;
var c:Number=90;
var num:int=12;
colr=(Math.sin((i*360/num+c)*Math.PI/180)+1)*255/2;
colg=(Math.sin((i*360/num+120+c)*Math.PI/180)+1)*255/2;
colb=(Math.sin((i*360/num-120+c)*Math.PI/180)+1)*255/2;
colr=255*br+colr*(1.0-br);
colg=255*br+colg*(1.0-br);
colb=255*br+colb*(1.0-br);
return colr*256*256+colg*256+colb;
}
public function grayScale(v:Number):int{
var col:int=v*255;
col=Math.max(Math.min(col,255),0);
return col*256*256+col*256+col;
}
}
}
