init(red:green:blue:alpha:exposure:)
Generates an HDR color 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)