如果你想要走下一条被拖走的道路,你自己就走了。 Apple果树脂中含有一种反应器,即从另一条途径(或只是中风)中回收。

如果你只想填满(如您的榜样形象),你就能够使用滑坡道路。 不过,你们必须使用一个trick子。 当你在滑坡道路上添加一条路时,新的滑坡道路是旧的滑坡道和附加道路的intersection。 因此,如果你只添加<条码>小马斯克帕塔,则你将最终在<条码>中填满区域,而这正是你想要的。

你们需要做的是,将现有的剪切路径与<条码>中文本<>>/m>连接起来。 幸运的是,你能够非常容易地利用 even夜规则。 http://developer.apple.com/library/ios/#documentation/GraphicsImaging/Conceptual/drawingwithquartz2d/dq_paths/dq_paths.html#/apple_ref/doc/uid/TP30001066-CH211-TPXREF106, Quartz 2D Program Guide 。

基本想法是,我们开辟一条有两条子的复合道路:smallMaskPath和一条完全随附<条码>的大型试金星,以及你希望填满的所有其他星。 由于偶然规则,在<条码>上的每一张钢材都将在复合道路之外处理,在<条码>上外的每张钢材都将在复合道路内处理。

So let s create this compound path. We ll start with the huge rectangle. And there is no rectangle more huge than the infinite rectangle:

UIBezierPath *clipPath = [UIBezierPath bezierPathWithRect:CGRectInfinite];

现在,我们通过添加<条码>中小马Mas/条码>,使之成为一个复合途径:

[clipPath appendPath:smallMaskPath];

接下来,我们确定了使用“ even”规则的道路:

clipPath.usesEvenOddFillRule = YES;

在我们走上这条道路之前,我们应当拯救图象国家,以便我们能够在我们重新努力时打破通往滑坡的道路的转变:

CGContextSaveGState(UIGraphicsGetCurrentContext()); {

我们现在可以修改滑坡道路:

    [clipPath addClip];

我们可以填写<代码>bigMaskPath:

    [[UIColor orangeColor] setFill];
    [bigMaskPath fill];

最后,我们恢复图形状态,改变lipp路:

} CGContextRestoreGState(UIGraphicsGetCurrentContext());

在这里,如果你想要复制/复制该守则:

UIBezierPath *clipPath = [UIBezierPath bezierPathWithRect:CGRectInfinite];
[clipPath appendPath:smallMaskPath];
clipPath.usesEvenOddFillRule = YES;

CGContextSaveGState(UIGraphicsGetCurrentContext()); {
    [clipPath addClip];
    [[UIColor orangeColor] setFill];
    [bigMaskPath fill];
} CGContextRestoreGState(UIGraphicsGetCurrentContext());

实际情况是,大多数案件都比较简单,例如:

path.append(cutout.reversing())

这是因为缺省填充规则是non-zero风化规则。

p = UIBezierPath(rect: .. )
let hole = UIBezierPath(ovalIn: ... )
p.append(hole.reversing())
p.usesEvenOddFillRule = false

以及

layerToUseAsUIViewMask.path = p
layer.mask = layerToUseAsUIViewMask

let hole = UIBezierPath(ovalIn: CGRect(
    origin: CGPoint(x: 70, y: 10), .. use -10 for the second demo above.
    size: CGSize(width: 50, height: 50))
)

p.append(hole.reversing()) // that s acw currently on iOS

p.append(hole) // that s cw currently on iOS

https://stackoverflow.com/a/590928/294884

Patrick provided an improvement/alternative to user NSResponder s answer by using the non-zero winding rule. Here is a full implementation in Swift for anyone that is looking for an expanded answer.

UIGraphicsBeginImageContextWithOptions(CGSize(width: 200, height: 200), false, 0.0)
let context = UIGraphicsGetCurrentContext()

let rectPath = UIBezierPath(roundedRect: CGRectMake(0, 0, 200, 200), cornerRadius: 10)
var cutoutPath = UIBezierPath(roundedRect: CGRectMake(30, 30, 140, 140), cornerRadius: 10)

rectPath.appendPath(cutoutPath.bezierPathByReversingPath())

UIColor.orangeColor().set()
outerForegroundPath.fill()

let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()

此处为。

你们可以把这一点放在一个故事板上,以了解和发挥产出的作用。

这里有两个透明的观点漏洞:

@IBDesignable
class HoleView: UIView {
    
    @IBInspectable
    var radius1: CGFloat = 10 { didSet { updateMask() } }
    
    @IBInspectable
    var XPositionPercent1: CGFloat = 90 { didSet { updateMask() } }
    
    @IBInspectable
    var YPositionPercent1: CGFloat = 50 { didSet { updateMask() } }
    
    
    @IBInspectable
    var radius2: CGFloat = 10 { didSet { updateMask() } }
    
    @IBInspectable
    var XPositionPercent2: CGFloat = 10 { didSet { updateMask() } }
    
    @IBInspectable
    var YPositionPercent2: CGFloat = 50 { didSet { updateMask() } }
    
    override func layoutSubviews() {
        super.layoutSubviews()
        
        updateMask()
    }
    
    private func updateMask() {
        
        let path = UIBezierPath(rect: bounds)
        path.usesEvenOddFillRule = false
        
        
        // MARK: Hole 1
        let XPos1 = (bounds.width * XPositionPercent1) / 100
        let YPos1 = (bounds.height * YPositionPercent1) / 100
        let center1 = CGPoint(x: XPos1, y: YPos1)
        
        let hole1 = UIBezierPath(arcCenter: center1,
                                 radius: radius1,
                                 startAngle: 0,
                                 endAngle: 2 * .pi,
                                 clockwise: true)
        path.append(hole1)
        
        // MARK: Hole 2
        let XPos2 = (bounds.width * XPositionPercent2) / 100
        let YPos2 = (bounds.height * YPositionPercent2) / 100
        let center2 = CGPoint(x: XPos2, y: YPos2)
        let hole2 = UIBezierPath(arcCenter: center2,
                                 radius: radius2,
                                 startAngle: 0,
                                 endAngle: 2 * .pi,
                                 clockwise: true)
        path.append(hole2)
        
        
        
        let mask1 = CAShapeLayer()
        mask1.fillRule = .evenOdd
        mask1.path = path.cgPath
        
        layer.mask = mask1
    }
}

Instead of subtracting, I was able to solve by creating a CGPath using CGPathAddLineToPoint and CGPathAddArcToPoint. This can also be done with a UIBiezerPath with similar code.