使用NSBezierPath只绘制星形边框

Question

使用NSBezierPath仅使用外表面绘制星形。下面的代码是与所有线相交的绘制星。

- (NSBezierPath *) getPathForStar{

    CGRect rect =self.frame;
    NSBezierPath * path = [NSBezierPath bezierPath];

    [path setLineWidth:2.0];
    CGFloat xCenter = rect.size.width / 2;
    CGFloat yCenter = rect.size.height / 2;

    float width;
    if(rect.size.width > rect.size.height) {
        width = rect.size.height;
    } else {
        width = rect.size.width;
    }
    double r = width / 2.0;
    float flip = -1.0;

    double theta = 2.0 * M_PI * (2.0 / 5.0); // 144 degrees

    [path moveToPoint:CGPointMake(xCenter, r*flip+yCenter)];

    for (NSUInteger k=1; k<5; k++)
    {
        float x = r * sin(k * theta);
        float y = r * cos(k * theta);
        [path lineToPoint:CGPointMake( x+xCenter, y*flip+yCenter)];
    }

     return path;
}

我想只绘制明星的边界。感谢。