嘿~~我正在尝试在其顶部绘制带有矩形手柄的实心圆点。(背景色:紫色,原色:黑色)
但是,所有形状都是正确的,但是当我着色时,在形状重叠区域会出现间隙,无法用纯色填充。
我应该如何纠正?谢谢!
var shapeLayer: CAShapeLayer!
func draw() {
let path = UIBezierPath()
// draw a rectangle
path.move(to: CGPoint(x: 90, y: 0))
path.addLine(to: CGPoint(x: 90, y: 100))
path.addLine(to: CGPoint(x: 110, y: 100))
path.addLine(to: CGPoint(x: 110, y: 0))
path.addLine(to: CGPoint(x: 90, y: 0))
// draw a circle
path.move(to: CGPoint(x: 100, y: 100))
path.addArc(withCenter: CGPoint(x: 100, y: 100), radius: 50, startAngle: 0, endAngle: 2 * CGFloat.pi, clockwise: true)
// fill colors with purple and black
self.shapeLayer.path = path.cgPath
self.shapeLayer?.fillColor = foreColor.cgColor
self.backgroundColor = backColor
}
以相反的方向绘制矩形:
// draw a rectangle
path.move(to: CGPoint(x: 90, y: 0))
path.addLine(to: CGPoint(x: 110, y: 0))
path.addLine(to: CGPoint(x: 110, y: 100))
path.addLine(to: CGPoint(x: 90, y: 100))
path.addLine(to: CGPoint(x: 90, y: 0))
[CoreGraphics使用的non-zero winding填充使用线条的方向来确定内部/外部。
或者,您可以反转圆的方向:
path.addArc(withCenter: CGPoint(x: 100, y: 100), radius: 50,
startAngle: 2 * CGFloat.pi, endAngle: 0, clockwise: false)
除了@vacawama的答案,我发现的另一种方法是,我可以使用非封闭矩形而不是封闭矩形,在与圆连接的一侧打开rect:
let path = UIBezierPath()
// an open rectangle
path.move(to: CGPoint(x: 90, y: 52))
path.addLine(to: CGPoint(x: 90, y: 0))
path.addLine(to: CGPoint(x: 110, y: 0))
path.addLine(to: CGPoint(x: 110, y: 52))
// the same circle
path.append(UIBezierPath(ovalIn: CGRect(x: 50, y: 50, width: 100, height: 100)))
这也可行,但是了解“非零缠绕规则”真的很好,非常棒,谢谢!
我现在很高兴:)