As3 带箭头直线的不同画法

来源：互联网发布：闪铸fdm打印机知乎编辑：程序博客网时间：2024/04/29 11:20

1:使用Math.cos、Math.sin组合画线

代码：

//一般画带箭头直线

function drawArrowWithVector(g:Graphics,x1:int,y1:int,x2:int,y2:int):void {

//箭头长度

var len:int = 10;

//箭头与直线的夹角

var _a:int = 30;

var angle:int = Math.atan2((y1-y2), (x1-x2))*(180/Math.PI);

//angle = Degree.fixAngle(angle);

g.lineStyle(lineWidth,0xff5566);

g.moveTo(x2,y2);

g.lineTo(x2+len*Math.cos((angle-_a)*(Math.PI/180)), y2+len*Math.sin((angle-_a)*(Math.PI/180)));

g.moveTo(x2,y2);

g.lineTo(x2+len*Math.cos((angle+_a)*(Math.PI/180)), y2+len*Math.sin((angle+_a)*(Math.PI/180)));

g.moveTo(x1,y1);

g.lineTo(x2,y2);

}

说明：该方法比第一种方法的灵活性要好出很多，不管节点怎么变化都可以准确的画出你想要的内容。具体用法：

var sp:Sprite=new Sprite()

var v1:Point=new Point(100,200);

var v2:Point=new Point(350,150);

drawArrowWithVector(sp.graphics,v1.x,v1.y,v2.x,v2.y);

this.addChild(sp);

2:使用Point.polar和Point.offset方法画线

代码：

//使用极坐标画线

private function drawArrowWithPolar(_g:Graphics,fP:Point,tP:Point):void{

var arrowBaseSize:Number = 10;//箭头两边距离中间线的距离

var arrowHeadLength:Number = 50;//箭头的长度

var lArrowBase:Point;

var rArrowBase:Point;

var mArrowBase:Point;

var edgeAngle:Number= Math.atan2(tP.y - fP.y,tP.x - fP.x);

mArrowBase = Point.polar(Point.distance(tP,fP) - arrowHeadLength,edgeAngle);

mArrowBase.offset(fP.x,fP.y);

lArrowBase = Point.polar(arrowBaseSize,(edgeAngle - (Math.PI / 2.0)));

rArrowBase = Point.polar(arrowBaseSize,(edgeAngle + (Math.PI / 2.0)));

lArrowBase.offset(mArrowBase.x,mArrowBase.y);

rArrowBase.offset(mArrowBase.x,mArrowBase.y);

/* now we actually draw */

//_g.beginFill(0xff5566);

_g.lineStyle(lineWidth,0xff5566);

_g.moveTo(fP.x, fP.y);

_g.lineTo(tP.x, tP.y);

_g.lineTo(lArrowBase.x, lArrowBase.y);

//_g.moveTo(tP.x,tP.y);

_g.lineTo(rArrowBase.x, rArrowBase.y);

_g.lineTo(tP.x, tP.y);

//_g.endFill();

}

使用方法：

var sp:Sprite=new Sprite()

var v1:Point=new Point(100,200);

var v3:Point=new Point(100,200);

var v4:Point=new Point(350,350);

drawArrowWithPolar(sp.graphics,v3,v4);

this.addChild(sp);

说明：个人觉得这个方法很有意思，有兴趣的朋友可以试着改变arrowBaseSize和arrowHeadLength的，看看具体的不同。