CGBlendMode.saturation
Uses the luminance and hue values of the background with the saturation of the source image. Areas of the background that have no saturation (that is, pure gray areas) don’t produce a change.
Declaration
case saturationUses the luminance and hue values of the background with the saturation of the source image. Areas of the background that have no saturation (that is, pure gray areas) don’t produce a change.
case saturation