swift - 将 CGImage 转换为 NSImage Swift

Question

我试图在 NSImageView 框中显示 CGImage，但我无法将 CGImage 转换为 NSImage。我应该如何处理这种情况？谢谢!

Answer 1

部分基于 Larme 的 comment :

• 对于 Swift，采用 CGImage 的 NSImage 初始值设定项是 init(cgImage:size:)语法示例是:

  let myNsImage = NSImage(cgImage: myCgImage, size: .zero)
  

  .zero 方便使用与 CGImage 相同的大小。

• 对于 Objective-C，请参阅 Getting NSImage from CGImageRef .

作为一个简化的演示(! 是故意的)，这个 macOS Playground 将在视觉上渲染 nsImage 与以编程方式生成的 cgImage 相同:

import AppKit
let colorSpace = CGColorSpaceCreateDeviceRGB()
let bitmapInfo = CGBitmapInfo.byteOrder32Big.rawValue | CGImageAlphaInfo.premultipliedLast.rawValue & CGBitmapInfo.alphaInfoMask.rawValue
let s: UInt32 = 0xffbbbbbb, o: UInt32 = 0xff3d85e6, f: UInt32 = 0x00000000
let width = 12; let height = 15
var pixels = [
    f, f, f, f, f, f, f, o, f, f, f, f, f, f, f, f, f, f, f, o, f, f, f, f, f, f, f, f, f, f, f, f, o, f, f, f, f, f, f, o, f, f, f, f, o, f, f, f, f, f, f, f, o, f, f, f, f, o, f, f, f, f, f, f, f, o, f, f, f, o, f, f, f, f, f, f, f, f, o, f, f, f, o, f, f, f, f, f, f, f, f, o, o, f, f, o, f, f, o, o, f, f, f, f, f, o, o, f, f, f, f, f, o, o, o, o, f, f, f, f, s, f, f, f, f, f, f, f, o, o, f, s, s, f, f, f, f, f, f, f, f, f, f, s, s, f, o, o, o, o, o, o, o, o, f, s, s, f, f, f, f, f, f, f, f, f, f, s, s, s, s, s, s, s, s, s, s, s, s, s,
]
var context: CGContext!
pixels.withUnsafeMutableBufferPointer { bufferPointer in
    context = CGContext(data: bufferPointer.baseAddress, width: width, height: height, bitsPerComponent: 8, bytesPerRow: width * 4, space: colorSpace, bitmapInfo: bitmapInfo, releaseCallback: nil, releaseInfo: nil)
}
let cgImage = context.makeImage()!
let nsImage = NSImage(cgImage: cgImage, size: .zero)
_ = nsImage