getHighContrastColor = transformsByColorSpaceKey[colorSpaceKey]
transformsByColorSpaceKey = ({
yiq: (c) => {
const darkenCoeff = getYiq(c) / maxLightness - 1.0;
if (darkenCoeff > 0) return c.darker(darkenCoeff);
return c;
},
lab: (c) => {
const lab = d3.lab(c);
if (lab.l > maxLightness) {
lab.l = maxLightness;
return lab.rgb();
}
return c;
},
hcl: (c) => {
const hcl = d3.hcl(c);
if (hcl.l > maxLightness) {
hcl.l = maxLightness;
return hcl.rgb();
}
return c;
},
cubehelix: (c) => {
const ch = d3.cubehelix(c);
if (ch.l > maxLightness) {
ch.l = maxLightness;
return ch.rgb();
}
return c;
}
})
inputsByColorSpaceKey = ({
yiq: Inputs.range([0, 255], {
step: 1,
label: "Maximum lightness",
value: 170
}),
lab: Inputs.range([0, 100], {
step: 1,
label: "Maximum lightness",
value: 85
}),
hcl: Inputs.range([0, 100], {
step: 1,
label: "Maximum lightness",
value: 85
}),
cubehelix: Inputs.range([0, 1], {
step: 0.01,
label: "Maximum lightness",
value: 0.85
})
})
d3 = require("d3@5")
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