是這樣宣告而來的,
private let bitmapInfo:CGBitmapInfo = CGBitmapInfo(CGImageAlphaInfo.PremultipliedFirst.toRaw())點過去看會發現,會發現有8種設定,
enum CGImageAlphaInfo : UInt32 { case None /* For example, RGB. */ case PremultipliedLast /* For example, premultiplied RGBA */ case PremultipliedFirst /* For example, premultiplied ARGB */ case Last /* For example, non-premultiplied RGBA */ case First /* For example, non-premultiplied ARGB */ case NoneSkipLast /* For example, RBGX. */ case NoneSkipFirst /* For example, XRGB. */ case Only /* No color data, alpha data only */ }
這時就看到一個陌生的單字"premultiplied",
請教google大神的翻譯,結果翻譯成中文是"預乘",
這翻譯應該還是難以理解吧?