Functions to measure and maximize accessibility.
contrastRatio : Color -> Color -> Basics.Float
Get the contrast ratio of two colors represented as a Float.
Formula based on: https://www.w3.org/TR/WCAG20/#contrast-ratiodef
contrastRatio Color.black Color.white -- 21.0
contrastRatio Color.blue Color.blue -- 1.0
luminance : Color -> Basics.Float
Get the relative luminance of a color represented as a Float.
Formula based on: https://www.w3.org/TR/WCAG20/#relativeluminancedef
luminance Color.black -- 0.0
luminance Color.white -- 1.0
maximumContrast : Color -> List Color -> Maybe Color
Returns the color with the highest contrast to the base color.
bgColor = Color.darkBlue
textOptions = [ Color.white, Color.purple, Color.black ]
maximumContrast bgColor textOptions -- Just Color.white