contrast-ratio ( color1 color2 -- n )

Vocabulary

colors.contrast

Inputs

color1	an object
color2	an object

Outputs

n

an object

Definition

USING: kernel math ;

IN: colors.contrast

: contrast-ratio ( color1 color2 -- n )
    [ relative-luminance ] bi@ 2dup < [ swap ] when
    [ 0.05 + ] bi@ / ;