ios - CIColor 到 UIColor -> CIColor 没有为 UIColor UIExtendedSRGBColorSpace 定义

Question

我正在尝试从 rgb-hex 色彩空间实现 CIColor，如下所示:

    let bottomColor = UIColor.init(red: 235/255, green: 250/255, blue: 255/255, alpha: 1.0).ciColor

但是，我不断遇到以下错误:

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -CIColor not defined for the UIColor UIExtendedSRGBColorSpace 0.921569 0.980392 1 1; need to first convert colorspace.'

我不确定这是什么意思。如何解决这个问题？

Answer 1

这会起作用:

let uiColor = UIColor.init(red: 235.0/255.0, green: 250.0/255.0, blue: 255.0/255.0, alpha: 1.0)
let bottomColor = CIColor(color: uiColor)

您还可以在 UIColor 上添加扩展:

extension UIColor {
    var coreImageColor: CIColor {
        return CIColor(color: self)
    }
    var components: (red: CGFloat, green: CGFloat, blue: CGFloat, alpha: CGFloat) {
        let color = coreImageColor
        return (color.red, color.green, color.blue, color.alpha)
    }
}

然后通过以下方式调用它:

let bottomColor = UIColor.init(red: 235.0/255.0, green: 250.0/255.0, blue: 255.0/255.0, alpha: 1.0).coreImageColor

我找到的答案和解释in this related question .