contrastrast
Version:
A lightweight tool that parses color strings and recommends text contrast based on WCAG Standards
23 lines (22 loc) • 1.06 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.contrastRatio = void 0;
const contrastrast_js_1 = require("../contrastrast.js");
const constants_js_1 = require("../constants.js");
/**
* Calculate the WCAG 2.1 contrast ratio between two colors
* @param color1 First color (Contrastrast instance or color string)
* @param color2 Second color (Contrastrast instance or color string)
* @returns Contrast ratio (1:1 to 21:1)
*/
const contrastRatio = (color1, color2) => {
const c1 = color1 instanceof contrastrast_js_1.Contrastrast ? color1 : new contrastrast_js_1.Contrastrast(color1);
const c2 = color2 instanceof contrastrast_js_1.Contrastrast ? color2 : new contrastrast_js_1.Contrastrast(color2);
const l1 = c1.luminance();
const l2 = c2.luminance();
const lighter = Math.max(l1, l2);
const darker = Math.min(l1, l2);
return (lighter + constants_js_1.CONTRAST_RATIO.LUMINANCE_OFFSET) /
(darker + constants_js_1.CONTRAST_RATIO.LUMINANCE_OFFSET);
};
exports.contrastRatio = contrastRatio;