ios - 无法使用类型为 'CGBitmapInfo' 的参数列表调用类型为 '(UInt32)' 的初始值设定项

Question

我将图像作为纹理添加到 Metal 球体中。使用 swift 2.0，但出现 CGBitmapInfo(options) 错误，它说:无法使用类型为“(UInt32)”的参数列表调用类型为“CGBitmapInfo”的初始值设定项...任何人都知道如何解决它？这是我的代码:

func textureForImage(image:UIImage, device:MTLDevice) -> MTLTexture?
{
    let imageRef = image.CGImage

    let width = CGImageGetWidth(imageRef)
    let height = CGImageGetHeight(imageRef)
    let colorSpace = CGColorSpaceCreateDeviceRGB()

    let rawData = calloc(height * width * 4, sizeof(UInt8))

    let bytesPerPixel = 4
    let bytesPerRow = bytesPerPixel * width
    let bitsPerComponent = 8

    let options = CGImageAlphaInfo.PremultipliedLast.rawValue | CGBitmapInfo.ByteOrder32Big.rawValue

    let context = CGBitmapContextCreate(rawData,
                                        width,
                                        height,
                                        bitsPerComponent,
                                        bytesPerRow,
                                        colorSpace,
                                        CGBitmapInfo(options))


    CGContextDrawImage(context, CGRectMake(0, 0, CGFloat(width), CGFloat(height)), imageRef)

    let textureDescriptor = MTLTextureDescriptor.texture2DDescriptorWithPixelFormat(.RGBA8Unorm,
                                                                                    width: Int(width),
                                                                                    height: Int(height),
                                                                                    mipmapped: true)
    let texture = device.newTextureWithDescriptor(textureDescriptor)

    let region = MTLRegionMake2D(0, 0, Int(width), Int(height))

    texture.replaceRegion(region,
                          mipmapLevel: 0,
                          slice: 0,
                          withBytes: rawData,
                          bytesPerRow: bytesPerRow,
                          bytesPerImage: bytesPerRow * height)

    free(rawData)

    return texture
}

Answer 1

在当前版本的 Swift 中，CGBitmapContextCreate 的最终参数是一个 UInt32，因此代替上面的 CGBitmapInfo(options)，您应该只传递 options(分配给 options 的表达式被推断为类型 UInt32)。