代码绘制六角形

绘制一个多角形
在as中实现:

 public static function drawStart(g:Graphics,num:uint,r:Number,
                                       fillColor:uint = 0xFF0000):void{
        var points:Array = [];
        var perAngle:Number = 180 / num;
        for(var i:int = 0;i<num*2;i++){
            if(i % 2){
                points.push(PointUtil.getPolarPoint(perAngle*i,r/2));
            }else{
                points.push(PointUtil.getPolarPoint(perAngle*i,r));
            }
        }

        g.clear();
        g.beginFill(fillColor,1);

        g.moveTo(points[0].x,points[0].y);

        for(var i:int = 1;i<points.length;i++){
            g.lineTo(points[i].x,points[i].y);
        }
        g.lineTo(points[0].x,points[0].y);
        g.endFill();
    }

在js中实现：

//简单模拟jquery的$函数
		function $(documentId){
			return document.getElementById(documentId);
		};

		function getPoint(angle,l){
			var radians = angle * Math.PI / 180;
			var x,y;
			x = l * Math.cos(radians);
			y = l * Math.sin(radians);
			return {
				x : x,
				y : y
			};
		};

		/** 绘制星星
		 * @param cId the canvas id
		 * @param num 外顶点数目
		 * @param r 半径长度
		 * @param fillcolor 填充颜色
		**/
		function drawStart (cId,num,r,fillcolor) {
			var c = $(cId);
			var ctx = c.getContext("2d");
			var points = [],perAngle = 180 / num;
			for(var i = 0;i<num*2;i++){
				if (i % 2) {
					points.push(getPoint(perAngle * i,r/2));
				} else{
					points.push(getPoint(perAngle * i,r));
				};
			};

			ctx.beginPath();
			ctx.strokeStyle = 0;
			ctx.fillStyle = fillcolor;
			ctx.moveTo(points[0].x + offsetX,points[0].y + offsetY);
			for(var j = 1;j<points.length;j++){
				ctx.lineTo(points[j].x + offsetX,points[j].y + offsetY);
			}
			ctx.lineTo(points[0].x + offsetX,points[0].y + offsetY);
			ctx.closePath();
			ctx.stroke();
			ctx.fill();
		};

		var offsetX = 40;
		var offsetY = 40;
		drawStart("canvas",6,15,"#ff0000");