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//
// Color.hsv().css
//
// RGB values are 0..255
// HSV values are 0..1
//
function compose(value)
return [
Math.round(value * 255),
Math.round(value * 255),
Math.round(value * 255)
}
}
class Color {
constructor(r, g, b, a) {
this.r = r
this.g = g
this.b = b
this.a = a
}
//
// alternate hsv factory
//
static hsv(h,s,v) {
let out = null
h = h % 360;
s = Math.max(0, Math.min(1, s))
v = Math.max(0, Math.min(1, v))
if (s == 0) {
let grey = Math.ceil(v*255)
out = [grey, grey, grey]
}
let b = ((1 - s) * v);
let vb = v - b;
let hm = h % 60;
switch((h/60)|0) {
case 0:
out = compose(v, vb * h / 60 + b, b); break
case 1:
out = compose(vb * (60 - hm) / 60 + b, v, b); break
case 2:
out = compose(b, v, vb * hm / 60 + b); break
case 3:
out = compose(b, vb * (60 - hm) / 60 + b, v); break
case 4:
out = compose(vb * hm / 60 + b, b, v); break
case 5:
out = compose(v, b, vb * (60 - hm) / 60 + b); break
}
return new Color(...out)
}
css() {
return `rgba(${this.r}, ${this.g}, ${this.b}, ${this.a})`
}
}
export default Color
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