Color.Accessibility

Accessibility

Functions to measure and maximize accessibility.

contrastRatio : Color -> Color -> 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 -> 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 -- Color.white