The avatar for @ijlyttle
Ian Lyttle
Public
Edited
Jul 18, 2023
Importers
8 stars
2
Computing on color
Color-Space ViewerChroma and Hue in Color SpacesLuminance in Color SpacesColor-Scale ViewerCategorical Color-Scale ViewerColor-Surface HelpersColor-Scale ThemesCategorical Color-Scale TryoutQuantitative Color-Scale TryoutAccessibility: Color-Contrast Models
Color-Vision-Deficiency Widget
Color Utilities
Also listed in…
Utilities
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viewof cvdExample = inputCvd({ condition: "none", label: "Custom label" })
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cvdExample
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dataCvd = FileAttachment("cvd.json").json()
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mapMatrixCvd = {
var result = new Map(
Object.entries(dataCvd).map(([k, v]) => [k, d3.piecewise(v)])
);

result.set("none", (t) => [
[1, 0, 0],
[0, 1, 0],
[0, 0, 1]
]);

return result;
}
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// (String, Number) -> Array
matrixCvd = function (condition, severity) {
return mapMatrixCvd.get(condition)(severity);
}
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matrixCvd("protan", 0.15)
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// string, number -> (color -> string)
//
// given a condition and a severity,
// returns a function that given a color,
// returns a hexcode
functionCvd = function (condition, severity) {
const mat = matrixCvd(condition, severity);

return function (color) {
const vec = Color.default(color).array().map(sRGB_to_linearRGB);

const vecCvd = math.multiply(mat, vec).map(linearRGB_to_sRGB);

return Color.default.rgb(vecCvd).hex();
};
}
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["#FF0000", "#00FF00", "#0000FF"].map(functionCvd("deuteran", 1.0))
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Color.default("red")
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import { changeTable } from "@ijlyttle/change-log"
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Color = import("https://cdn.skypack.dev/color@4.2.3")
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Color.default("red").array()
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math = import("https://cdn.skypack.dev/mathjs@11.5.1?")
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sRGB_to_linearRGB = function (x) {
x = x / 255;
const y = x <= 0.03928 ? x / 12.92 : Math.pow((x + 0.055) / 1.055, 2.4);
return y * 255;
}
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linearRGB_to_sRGB = function (y) {
y = y / 255;
const x =
y <= 0.03928 / 12.92 ? 12.92 * y : 1.055 * Math.pow(y, 1 / 2.4) - 0.055;
return x * 255;
}
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