cocoa - NSBezierPath を CGPath に変換するにはどうすればよいですか

Question

NSBezierPathの間で変換するにはどうすればよいですかCGPath。

ありがとう。

Answer 1

Apple のドキュメントから右: NSBezierPath オブジェクトから CGPathRef を作成する

関連するコードは次のとおりです。

@implementation NSBezierPath (BezierPathQuartzUtilities)
// This method works only in OS X v10.2 and later.
- (CGPathRef)quartzPath
{
    int i, numElements;

    // Need to begin a path here.
    CGPathRef           immutablePath = NULL;

    // Then draw the path elements.
    numElements = [self elementCount];
    if (numElements > 0)
    {
        CGMutablePathRef    path = CGPathCreateMutable();
        NSPoint             points[3];
        BOOL                didClosePath = YES;

        for (i = 0; i < numElements; i++)
        {
            switch ([self elementAtIndex:i associatedPoints:points])
            {
                case NSMoveToBezierPathElement:
                    CGPathMoveToPoint(path, NULL, points[0].x, points[0].y);
                    break;

                case NSLineToBezierPathElement:
                    CGPathAddLineToPoint(path, NULL, points[0].x, points[0].y);
                    didClosePath = NO;
                    break;

                case NSCurveToBezierPathElement:
                    CGPathAddCurveToPoint(path, NULL, points[0].x, points[0].y,
                                        points[1].x, points[1].y,
                                        points[2].x, points[2].y);
                    didClosePath = NO;
                    break;

                case NSClosePathBezierPathElement:
                    CGPathCloseSubpath(path);
                    didClosePath = YES;
                    break;
            }
        }

        // Be sure the path is closed or Quartz may not do valid hit detection.
        if (!didClosePath)
            CGPathCloseSubpath(path);

        immutablePath = CGPathCreateCopy(path);
        CGPathRelease(path);
    }

    return immutablePath;
}
@end

バグレポーター

rdar://15758302 : NSBezierPath から CGPath へ。

Answer 2

Xcode 8 GM の構文はさらに簡素化され、コードは上記の rob-mayoff の回答から変更されました。これとヘルパーを使用して、addLine(to point: CGPoint)描画コードをクロスプラットフォームで共有しています。

extension NSBezierPath {

    public var cgPath: CGPath {
        let path = CGMutablePath()
        var points = [CGPoint](repeating: .zero, count: 3)

        for i in 0 ..< elementCount {
            let type = element(at: i, associatedPoints: &points)
            switch type {
            case .moveTo:
                path.move(to: points[0])
            case .lineTo:
                path.addLine(to: points[0])
            case .curveTo:
                path.addCurve(to: points[2], control1: points[0], control2: points[1])
            case .closePath:
                path.closeSubpath()
            @unknown default:
                continue
            }
        }

        return path
    }
}

Answer 3

これは Swift 3.1 以降で機能します。

import AppKit

public extension NSBezierPath {

    public var cgPath: CGPath {
        let path = CGMutablePath()
        var points = [CGPoint](repeating: .zero, count: 3)
        for i in 0 ..< self.elementCount {
            let type = self.element(at: i, associatedPoints: &points)
            switch type {
            case .moveToBezierPathElement: path.move(to: points[0])
            case .lineToBezierPathElement: path.addLine(to: points[0])
            case .curveToBezierPathElement: path.addCurve(to: points[2], control1: points[0], control2: points[1])
            case .closePathBezierPathElement: path.closeSubpath()
            }
        }
        return path
    }

}

Answer 4

macOS のより良い使用 - CGMutablePath

しかし、あなたがしたいcgPath場合NSBezierPath：

スイフト5.0

extension NSBezierPath {

  var cgPath: CGPath {
    let path = CGMutablePath()
    var points = [CGPoint](repeating: .zero, count: 3)
    for i in 0 ..< self.elementCount {
      let type = self.element(at: i, associatedPoints: &points)

      switch type {
      case .moveTo:
        path.move(to: points[0])

      case .lineTo:
        path.addLine(to: points[0])

      case .curveTo:
        path.addCurve(to: points[2], control1: points[0], control2: points[1])

      case .closePath:
        path.closeSubpath()

      @unknown default:
        break
      }
    }
    return path
  }
}