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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
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{
  
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/* -------------- POINT.JS ------------*/
var Point = function(x,y) {
	this.x = x;
	this.y = y;
};

Point.prototype = {
	
	x:0,
	y:0,
	subtract:function(p) {
		return new Point(this.x-p.x,this.y-p.y)
	},
	
	add:function(p) {
		return new Point(this.x+p.x,this.y+p.y)
	},
	
	clone:function() {
		return new Point(this.x,this.y);
	},
	
	getNormal:function() {
		return new Point(-this.y,this.x);
	},

	angle:function() {
		return Math.atan2(this.y,this.x);
	},
		
	fromPolar:function (angle, length) {
		var l = length||1;
		return new Point(l*Math.cos(angle),l*Math.sin(angle));
	},

	lerp:function(a,b,pi) {
		this.x = pi*b.x+(1-pi)*a.x;
		this.y = pi*b.y+(1-pi)*a.y;
		return this;
	},
	
	scaleBy:function(amt) {
		this.x*=amt;
		this.y*=amt;
		return this;
	},
	
	length:function() {
		return Math.sqrt(this.x*this.x+this.y*this.y)
	},
	dot:function(b) {
		return this.x*b.x+this.y*b.y;
	},
	
	normalize:function(len) {
		var mag = len||1;
		var curLen = this.length();
		this.x/=curLen/mag;
		this.y/=curLen/mag;
		return this;
	},
	
	mean:function(pointList) {
		var x = 0;
		var y = 0;
		for(var i  = 0;i<pointList.length;i++) 
		{
			x+=pointList[i].x;
			y+=pointList[i].y;
		}
		x/= pointList.length;
		y/= pointList.length;
		return new Point(x,y);
	}
	
};

/*------------UTIL.JS------------*/

var Util = {
	
	STANDARD:0,
	REQUIRES_POSITIVE_T:1,
	REQUIRES_POSITIVE_U:2,
	REQUIRES_POSITIVE_BOTH:3,
	scalePoints:function(pts,amount, origin)
	{
	
		var outPoints = [];
		if(origin==null) 
		{
			origin = new Point().mean(pts);
		}
		
		for(var i =0;i<pts.length;i++) 
		{
			var pIn = pts[i];
			var pOut =  pts[i].subtract(origin).scaleBy(amount).add(origin);
			outPoints.push(pOut);
		}
	
		return outPoints;
	
	},
	reflect:function(ray, normal)
	{
		var v = ray.clone();
		var l = normal.clone();
		v.normalize();
		l.normalize();
		var reflection = l.scaleBy(2*(v.dot(l))/(l.dot(l))).subtract(v)
		return reflection;
		
	
	},
	
	intersectPolygon:function(a_p1,a_r1, polygon,mode) {
		//let's look for the one with the lowest positive t-value...
		// x("checking...",a_p1,a_r1,polygon);
		if(mode==undefined) mode==1;
		
		var points = polygon.points
		var collisionCandidates = [];
		var sideLength =  points[0].subtract(points[1]).length();
		
		for(var i = 0;i<points.length;i++)
		{
			var p2 = points[i]; 
			var pNext = points[(i+1)%points.length];
			var r2 = points[i].subtract(pNext);
			r2.normalize();
			var colSet = Util.intersect(a_p1,a_r1,points[i],r2);
			colSet.a = p2;
				 colSet.b = pNext;
			
			if(Math.abs(colSet.tValue)>1e-5) {
				 if(mode==1&&colSet.tValue>0) collisionCandidates.push(colSet);
				 if(mode==2&&colSet.uValue>0) collisionCandidates.push(colSet);
				 if(mode==0) {
				 colSet.tValue = Math.abs(colSet.tValue);
				 
				 collisionCandidates.push(colSet);
				 } if(mode==3&&colSet.tValue>0&&colSet.uValue>0&&colSet.uValue<sideLength)
				 {
					collisionCandidates.push(colSet);
				 }
			}
		}
			if(collisionCandidates.length==0) {
			
				return null;
			
			}
			collisionCandidates.sort(function(a,b) {return a.tValue-b.tValue;});
			
			
			var best = collisionCandidates[0];
			// console.log(best);
			var pt = new Point(best.xIntercept,best.yIntercept);
			pt.tValue = best.tValue;
			pt.uValue = best.uValue;
			console.log("adding an a and b - ",best.a,best.b)
			pt.a = best.a;
			pt.b = best.b;
			return pt;
	
	},
	
	
	intersect:function (a_p1,a_r1,a_p2,a_r2) {
		
			
			a_r1.normalize(1);
			a_r2.normalize(1);
			var returner= new Object();
			try {
				var ta = a_r1.y/a_r1.x;
				var tb = a_p1.y-ta*a_p1.x;
				
				
				
				var tc = a_r2.y/a_r2.x;
				var td = a_p2.y-tc*a_p2.x;
				/*trace("Intermediaries:\n-----------");
				we have y = ax+b
				and y=cx+d.
				if c
				
				*/
				
				/*trace("a:"+ta);
				trace("b:"+tb);
				trace("c:"+tc);
				trace("d:"+td);
				*/
				returner.xIntercept = (td-tb)/(ta-tc);
				returner.yIntercept = ta*returner.xIntercept +tb;
				
				if (Math.abs(ta)==Infinity) {
					//r1 is vertical
					returner.xIntercept = a_p1.x;
					returner.yIntercept = tc * returner.xIntercept + td;
					
				} else if (Math.abs(tc)==Infinity) {
					//r2 is vertical
					returner.xIntercept = a_p2.x;
					returner.yIntercept = returner.xIntercept * ta + tb;
				} else if(Math.abs(ta)==0) {
					//r1 is horizontal
					returner.yIntercept = a_p2.y; //
					returner.xIntercept =  (returner.yIntercept-td)/tc  ;
				}
				var m = returner.xIntercept;
				var p = a_p1.x;
				var q = a_r1.x;
				/*
				 * The approach that seems to work more robustly is 
				 * that we have the x-intercept.  
				 * if we divide the difference between the origin, a_p1.x, by the 
				 * ray's x magnitude, a_p1.x-a_r1.x, 
				 * */
				
				// returner.tValue  = (returner.xIntercept - a_p1.x) / (a_r1.x);
				if (returner.xIntercept == a_p1.x) {
					//we'll use yIntercept.
					// returner.tValue = (returner.yIntercept - a_p1.y) / (a_r1.y);
				}
				
				returner.tValue  = (a_p1.x-returner.xIntercept ) / (a_r1.x);
				returner.uValue  = (a_p2.x-returner.xIntercept ) / (a_r2.x);
				// if (returner.xIntercept == a_r2.x) {
					// we'll use yIntercept.
					// returner.uValue = (returner.yIntercept - a_r2.y) / (a_r2.y);
				// }
				
				returner.mirrorPi = (returner.xIntercept-a_r2.x)/(a_p2.x-a_r2.x);
			} catch (e) {
				
			}
			returner.point = new Point(returner.xIntercept,returner.yIntercept);
			return returner;
		},
		drawSketchStroke:function(a,b,g,extension,innerAlpha,jitter) {
		
		if(extension==null) extension = 100;
		if(innerAlpha==null) innerAlpha = 1;
		if(jitter==null) jitter = 0;
		var len = a.subtract(b).length();
		var overshootAmount =  (len+extension)/len;
		var overshoot = Util.scalePoints([a,b],overshootAmount)
		
		g.beginPath();
		
		// var grad = g.createLinearGradient(mousePoint.x,mousePoint.y, os.points[i].x,os.points[i].y);
		var grad = g.createLinearGradient(overshoot[0].x,overshoot[0].y,overshoot[1].x,overshoot[1].y);
		grad.addColorStop(0,"rgba(20,0,0,0)");
		grad.addColorStop(0.1,"rgba(20,0,0,"+innerAlpha+")");
		grad.addColorStop(0.9,"rgba(20,0,0,"+innerAlpha+")");
		grad.addColorStop(1,"rgba(20,0,0,0)");
		g.strokeStyle = grad;
		// this.drawRay(os.points[i], ray, g);
		g.moveTo(overshoot[0].x,overshoot[0].y);
		var segments = 10;
		var normal = a.subtract(b).normalize().getNormal();
		for(var i =0;i<segments;i++){
			var normalOffset = normal.clone().scaleBy((Math.random()-0.5)*jitter);
			var pInternal = new Point().lerp(a,b,i/segments).add(normalOffset);
			g.lineTo(pInternal.x,pInternal.y);
		}
		
		g.lineTo(overshoot[1].x,overshoot[1].y);
		
		g.stroke();
	
	},
	
	drawRay:function(p,r,g,drawHead) {
	
	
		if(drawHead==null) drawHead = false;
		g.moveTo(p.x,p.y);
		
		var headSize = 10;
		var tangent = (r);
		tangent.normalize();
		normal = tangent.getNormal();
		
		var head = new Point(p.x+100*r.x,p.y+100* r.y);
		
		g.lineTo(p.x+1000*r.x,p.y+1000* r.y);
		if(drawHead)
		{
		g.moveTo(head.x,head.y)
		g.lineTo(head.x+headSize*normal.x-headSize*tangent.x,head.y+headSize*normal.y-headSize*tangent.y);
		g.moveTo(head.x,head.y)
		g.lineTo(head.x-headSize*normal.x-headSize*tangent.x,head.y-headSize*normal.y-headSize*tangent.y);
		}
	},

	};



/*-------REGULARPOLYGON.JS--------*/

var RegularPolygon = function (center, radius, sides,angleOffset) {
	this.init(center,radius,sides,angleOffset);
}
RegularPolygon.prototype = {
	points:[],
	fillColor:null,
	init:function (center,radius, sides,angleOffset) {
		angleOffset= angleOffset||0;
		sides= sides||3;
		var theta = 2*Math.PI/sides;
		this.points = [];
		for(var i = 0;i<sides;i++)
		{
			var pt = new Point(
							center.x+radius*Math.sin(angleOffset+i*theta),
							center.y-radius*Math.cos(angleOffset+i*theta));
			this.points.push(pt);
		}
	
	},
	
	isInside:function isInside(p) {
	//first, we generate a ray that enters from the left and passes through the polygon through the point in question. Then we count the number of intersections 
	//- if it's odd, it's inside
	//- if it's even, it's outside.
	
	//generate the ray origin
	
		var rayOrigin = new Point(p.x-1000,p.y+10);
		
		for(var i =0 ;i<this.points.length;i++)
		{
			var pI = this.points[(i+this.points.length+0)%this.points.length];
			var pN = this.points[(i+this.points.length+1)%this.points.length];
			
			var rN = pI.subtract(pN).normalize();
			var r2 = rayOrigin.subtract(p);
			var ii = Util.intersect(rayOrigin, r2, pI,rN);
			
			if(ii)
			{
				g.beginPath();
				g.fillStyle = "rgba(255,255,255,0.5)";
				g.arc(ii.point.x,ii.point.y, 4,0,7);
				g.fill();
				
				
				
			}
		}
		
	
		
		
	},
	
	draw:function(g) {
		g.beginPath();
		if(this.fillColor) g.fillStyle = this.fillColor;
		if(this.strokeStyle) g.strokeStyle = this.strokeStyle;
		if(this.lineWidth) g.lineWidth = this.lineWidth;
			g.moveTo(this.points[0].x,this.points[0].y);
			for(var i  =0 ;i<this.points.length;i++) 
			{
				g.lineTo(this.points[i].x,this.points[i].y);
			}
			g.lineTo(this.points[0].x,this.points[0].y);
		if(this.fillColor) {
			// console.log("finishing?");
			g.fill();
		}
		if(this.strokeStyle) g.stroke();
		
	},
	
	
	
	drawRounded:function(radius,g,offset) {
		// radius =1;
		if(this.lineWidth!=null) g.lineWidth = this.lineWidth;
		if(this.fillColor) g.fillStyle = this.fillColor;
		if(this.strokeStyle) g.strokeStyle = this.strokeStyle;
		g.beginPath();

		var polyPoints = [];
		
		//we need to be able to shift the points in and out... 
		var pts = this.points;
	
		var newPts = [];
		
		var p = this.points;
		g.beginPath();
		
		//----PATH OFFSET
		
		for(var i =0;i<this.points.length;i++)
		{
			//TODO resolve this to compensate for acute angles! There needs to be a feature of this that includes the sin of the angle, or maybe 1/sin, since offsets have to be pushed out further if we're working on mitre offsets.
			
			var pI = p[i];
			var pL = p[(i+p.length-1)%p.length];
			var pN = p[(i+p.length+1)%p.length];
			
			var rL = pL.subtract(pI).normalize();//.add(pI);
			var rN = pN.subtract(pI).normalize();//.add(pI);
			var nL = rL.getNormal();
			var nN = rN.getNormal();
			var thisAngle = rL.angle()-rN.angle();
			var concave = (thisAngle>0||Math.abs(thisAngle)>Math.PI);
			var thisOffset = offset/Math.sin(thisAngle);
			var avgN = new Point().lerp(rL,rN,0.5);
			avgN.scaleBy(concave?thisOffset:thisOffset);
			newPts.push(pI.subtract(avgN));
			// lt(pI.subtract(avgN),g);
		}
			// lt(newPts[0],g);
			// g.stroke();
		
		pts = newPts;
		
		//CORNER ROUNDING
		
		
		for(var i =0;i<pts.length;i++)
		// for(var i =0;i<;i++)
		{
			var pI = pts[i];
			var pL = pts[(i+pts.length-1)%pts.length];
			var pN = pts[(i+pts.length+1)%pts.length];
			
			
			var rL = pL.subtract(pI).normalize();//.add(pI);
			var rN = pN.subtract(pI).normalize();//.add(pI);

			var thisAngle = rL.angle()-rN.angle();
			var concave = (thisAngle>0||Math.abs(thisAngle)>Math.PI);
			if(thisAngle>Math.PI&&thisAngle<Math.PI*2) concave = false;
			var sign = concave?1:-1;
			var theta = thisAngle/1;
			var radiusI =  Math.max(1,radius+offset*sign);
			var radInset = (radiusI/Math.sin(theta));
			//next, the relative points:
			g.fillStyle ="white";
			//so we have the inset, which is where to cast back  from.
			// g.fillText(radInset.toFixed(2),pI.x,pI.y+20);
			// g.fillText((thisAngle*57).toFixed(1)+", "+ concave,pI.x,pI.y+30);
			
			var avgN = new Point().lerp(rL,rN,0.5);
			avgN.scaleBy(concave?radInset:-radInset);
			// g.beginPath();
			// mt(pI,g);
			// lt(pI.add(avgN),g);
			// g.stroke();

		
			// rL.scaleBy(radiusI);
			// rN.scaleBy(radiusI);
			var nL = rL.getNormal();
			var nN = rN.getNormal();
			
			nL.scaleBy(radiusI/2*sign);
			nN.scaleBy(radiusI/2*sign);
			
			rL = rL.add(pI);
			var insetPoint =  pI.add(avgN);
			
			var oldStroke = g.strokeStyle;
			// g.strokeStyle = "red";
			g.beginPath();
			
			// g.arc(insetPoint.x,insetPoint.y,4,0,7);
			
			g.stroke();
			 g.strokeStyle=oldStroke;
			
			g.beginPath();
			// g.arc(insetPoint.x,insetPoint.y,Math.abs(radiusI)/2,0,7);
			
			g.stroke();
			
			g.beginPath();
			// g.arc(insetPoint.x,insetPoint.y,4,0,7);
			
			g.stroke();
			
			rL = insetPoint.add(nL);
			rN = insetPoint.subtract(nN);
			// g.beginPath();
			// g.arc(rL.x,rL.y,2,0,7);
			
			// g.stroke();
			// g.beginPath();
			// g.arc(rN.x,rN.y,2,0,7);
			
			// g.stroke();
			
			
			//then the two corners are actually radiusI*nL+insetPoint and radiusI*nR+insetPoint. 
			
			// var insetPoint =  rL.add(rN);
			//now maybe we can get the circle 
			// rN = rN.add(pI);
			
			polyPoints.push(rL);
			polyPoints.push(rN);
			
			//then we need to cast that back to r from the 
			
			var rI = insetPoint;
			// .subtract(pI);
			// rI.normalize();
			// rI.scaleBy(radius);
			// rI = rI.add(pI);
	
	
			// g.stroke();
			// g.lineWidth = 1;
			// g.fillStyle = "green";
			// g.beginPath();
				// g.arc(rN.x,rN.y,5,0,7);
			// g.fill();
			
			// g.fillStyle = "blue";
			// g.beginPath();
				// g.arc(rL.x,rL.y,5,0,7);
			// g.fill();
			
			// g.fillStyle = "black";
			// g.beginPath();
				// g.arc(insetPoint.x,insetPoint.y,5,0,7);
			// g.fill();
			

			var theta1 = Math.atan2(rN.y-insetPoint.y,rN.x-insetPoint.x);
			var theta2 = Math.atan2(rL.y-insetPoint.y,rL.x-insetPoint.x);
			


			//maybe we should try a quadraticcurveto...
			
			// g.lineWidth = 1;
			if(false&&(new Date().getTime()%2000)>1000)
			{
			g.moveTo(rL.x,rL.y);
			// g.quadraticCurveTo(pI.x,pI.y,rN.x,rN.y);
			} else 
			{
			g.beginPath();
				if(concave)
				g.arc(rI.x,rI.y,radiusI/2,theta2,theta1);
				else
				g.arc(rI.x,rI.y,radiusI/2,theta1,theta2);
			}
			g.stroke();

			
			
			//so that's good. we have the points and we have the radii we'll need to grab the points for:
		}

		
		
		g.lineWidth = this.lineWidth;

		//---LINE SEGMENTS
		
		g.beginPath();
		if(polyPoints.length<1) return;
			g.moveTo(polyPoints[0].x,polyPoints[0].y);
			for(var i  =1 ;i<polyPoints.length-1;i+=2) 
			{
				g.moveTo(polyPoints[i].x,polyPoints[i].y);
				g.lineTo(polyPoints[i+1].x,polyPoints[i+1].y);
			}
				g.moveTo(polyPoints[polyPoints.length-1].x,polyPoints[polyPoints.length-1].y);
				g.lineTo(polyPoints[0].x,polyPoints[0].y);

		
		if(this.fillColor) {
				g.fill();
			}
		
			if(this.strokeStyle) g.stroke();

			
		
		
	},
	
	end:null,
}






var c = document.createElement("canvas");
 document.body.appendChild(c);
  var g = c.getContext("2d");
c.width = window.innerWidth;

function update() {
c.height = window.innerHeight;
var count = c.width/17;
for(var y = 0;y<43;y++) {
  for(var i =0 ;i<count;i++){

    var even = (i+y)%2==0;
    
    var rpI = new RegularPolygon(new Point(50+17*i,30*y+(even?200:190)-200), 20.2, 3,even?0:Math.PI);
    rpI.fillColor = "rgba(0,0,0,"+(i/count+0.1*(0.5+0.45*Math.sin(y/323.62*i/5*new Date().getTime()*0.01)))+")";
    rpI.draw(g);

   
    
  }
}
requestAnimationFrame(update);

  
}

update();



            
          
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