如何计算＆＃34;中心＆＃34;弯曲的SKSpriteNode点？

Question

我通过SKShapeNode的纹理初始化并显示SKSpriteNode，该纹理具有代表圆的一部分的特定路径。下面是我使用游乐场生成的形状示例：

import SpriteKit
import PlaygroundSupport

let view = SKView(frame: CGRect(x: 0, y: 0, width: 300, height: 300))
let scene = SKScene(size: view.frame.size)
view.presentScene(scene)

let radius: CGFloat = view.frame.width * 0.40

var length: CGFloat = (.pi * 2.0) / 8.0
var width: CGFloat  = radius / 5.0

var path: CGPath {

    let path = UIBezierPath(arcCenter: view.center, radius: radius, startAngle: 0.0, endAngle: length, clockwise: true)
    path.addArc(withCenter: view.center, radius: radius - width, startAngle: length, endAngle: 0.0, clockwise: false)

    path.close()

    return path.cgPath
}

let shapeNode = SKShapeNode(path: path)
shapeNode.fillColor = .white
let texture = view.texture(from: shapeNode)!

let spriteNode = SKSpriteNode(texture: texture, color: .white, size: texture.size())
spriteNode.position = CGPoint(x: shapeNode.frame.midX, y: shapeNode.frame.midY)

scene.addChild(spriteNode)

PlaygroundPage.current.liveView = view

这会产生这种形状：

我想添加一个小孩子SKSpriteNode，它位于弯曲节点的宽度和中间弧点的中心，如下所示：

我最接近的是使用spriteNode的位置：

let childNode = SKSpriteNode(color: .red, size: CGSize(width: 5, height: 5))
childNode.position = spriteNode.position
scene.addChild(childNode)

这会产生一些接近的东西，但它使用的是框架，这是完全错误的：

我假设我需要对弧线的路径做些什么，但我不确定如何做。有人能指出我正确的方向吗？

Answer 1

感谢评论，我避免使用路径并刷新一些基本的触发来解决：

/****** Object:  UserDefinedFunction [dbo].[BUSINESS_DURATION_MINTS_FN]    Script Date: 10/17/2017 12:22:12 PM ******/
SET ANSI_NULLS OFF
GO

SET QUOTED_IDENTIFIER ON
GO


ALTER FUNCTION [dbo].[BUSINESS_DURATION_MINTS_FN]
(@string varchar(100) )
RETURNS INT 
AS



BEGIN
 DECLARE  @total_mints INT
 DECLARE  @hours INT
 DECLARE  @Mints INT
 IF @string IS NOT NULL
 BEGIN
 SET @string = REPLACE(UPPER(@string),'HOURS','HOUR')
 SET @string = REPLACE(UPPER(@string),'MINUTES','MINUTE')
IF  ((CHARINDEX(UPPER('HOUR'),UPPER(@string))!=0)  AND (CHARINDEX(UPPER('MINUTE'),UPPER(@string))!= 0)) 

   BEGIN
   SET  @hours = CONVERT(INT,SUBSTRING(@string,1, (CHARINDEX(UPPER('HOUR'), UPPER(@string))-2))) 
   SET  @Mints = CONVERT(INT,SUBSTRING(@string,(CHARINDEX(UPPER('HOUR'),UPPER(@string))+4),(CHARINDEX(UPPER('MINUTE'),UPPER(@string))-(CHARINDEX(UPPER('HOUR'), UPPER(@string))+5))))
   END


   IF  ((CHARINDEX(UPPER('HOUR'),UPPER(@string))=0)  AND (CHARINDEX(UPPER('MINUTE'),UPPER(@string))!= 0)) 
   BEGIN
  SET  @hours = 0
   SET  @Mints = CONVERT(INT,SUBSTRING(@string,1, (CHARINDEX(UPPER('MINUTE'), UPPER(@string))-2)))
   END


  IF  ((CHARINDEX(UPPER('HOUR'),UPPER(@string))!=0)  AND (CHARINDEX(UPPER('MINUTE'),UPPER(@string))=0)) 
   BEGIN
   SET  @hours = CONVERT(INT,SUBSTRING(@string,1, (CHARINDEX(UPPER('HOUR'), UPPER(@string))-2))) 
  SET  @Mints = 0
   END

   IF  ((CHARINDEX(UPPER('HOUR'),UPPER(@string))= 0)  AND (CHARINDEX(UPPER('MINUTE'),UPPER(@string))=0)) 
   BEGIN
   SET  @hours = 0    
   SET  @Mints = 0
   END

   SET  @total_mints = @hours*60 + @Mints


  END
  IF  @string IS NULL
  BEGIN
  SET @total_mints = NULL

  END
     RETURN @total_mints

END


GO