init(red:green:blue:alpha:exposure:)
Generates an HDR color in the extended sRGB colorspace by applying an exposure to the SDR color defined by the red, green, and blue components. The red, green, and blue components have a nominal range of [0..1], exposure is a value >= 0. To produce an HDR color, we process the given color in a linear color space, multiplying component values by 2^exposure. The produced color will have a contentHeadroom equal to the linearized exposure value. Each whole value of exposure produces a color that is twice as bright.
Declaration
init(red: CGFloat, green: CGFloat, blue: CGFloat, alpha: CGFloat, exposure: CGFloat)