Question

我正在尝试基于点阵列创建自定义SKShapeNode。这些点形成一个封闭的形状，最终需要填充形状。

这是我到目前为止所提出的，但由于某种原因，笔画很好但形状仍然是空的。我错过了什么？

override func didMoveToView(view: SKView)
{
    let center = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame))
    let path = CGPathCreateMutable()


    CGPathMoveToPoint(path, nil, center.x, center.y)
    CGPathAddLineToPoint(path, nil, center.x + 50, center.y + 50)

    CGPathMoveToPoint(path, nil, center.x + 50, center.y + 50)
    CGPathAddLineToPoint(path, nil, center.x - 50, center.y + 50)

    CGPathMoveToPoint(path, nil, center.x - 50, center.y + 50)
    CGPathAddLineToPoint(path, nil, center.x - 50, center.y - 50)

    CGPathMoveToPoint(path, nil, center.x - 50, center.y - 50)
    CGPathAddLineToPoint(path, nil, center.x, center.y)

    CGPathCloseSubpath(path)

    let shape = SKShapeNode(path: path)
    shape.strokeColor = SKColor.blueColor()
    shape.fillColor = SKColor.redColor()
    self.addChild(shape)
}

Answer 1

List[String]出了问题。您通常会调用path来设置路径的起点，然后进行一系列CGPathMoveToPoint调用以将路段添加到路径中。尝试像这样创建它：

CGPathAdd*

阅读CGPath Reference（搜索let path = CGPathCreateMutable() CGPathMoveToPoint(path, nil, center.x, center.y) CGPathAddLineToPoint(path, nil, center.x + 50, center.y + 50) CGPathAddLineToPoint(path, nil, center.x - 50, center.y + 50) CGPathAddLineToPoint(path, nil, center.x - 50, center.y - 50) CGPathCloseSubpath(path)）了解详情。

Answer 2

例如，您不需要使用CGPath进行此操作，您可以这样做：

let points: [CGPoint] = [CGPointMake(center.x, center.y), ...] // All your points
var context: CGContextRef = UIGraphicsGetCurrentContext()

CGContextAddLines(context, points, UInt(points.count))
CGContextSetFillColorWithColor(context, UIColor.redColor().CGColor)
CGContextFillPath(context)

let shape = SKShapeNode(path: CGContextCopyPath(context))
...

填充从CGPath创建的SKShapeNode

2 个答案: