@visactor/vscale/es/threshold-scale.js

Scales for visual encoding, used in VGrammar, VTable

import { isNil, isValidNumber, bisect } from "@visactor/vutils";

import { ScaleEnum } from "./type";

export class ThresholdScale {
    constructor() {
        this.type = ScaleEnum.Threshold, this._range = [ 0, 1 ], this._domain = [ .5 ], 
        this.n = 1;
    }
    unknown(_) {
        return arguments.length ? (this._unknown = _, this) : this._unknown;
    }
    scale(x) {
        return !isNil(x) && isValidNumber(+x) ? this._range[bisect(this._domain, x, 0, this.n)] : this._unknown;
    }
    invertExtent(y) {
        const i = this._range.indexOf(y);
        return [ this._domain[i - 1], this._domain[i] ];
    }
    domain(_) {
        return _ ? (this._domain = Array.from(_), this.n = Math.min(this._domain.length, this._range.length - 1), 
        this) : this._domain.slice();
    }
    range(_) {
        return _ ? (this._range = Array.from(_), this.n = Math.min(this._domain.length, this._range.length - 1), 
        this) : this._range.slice();
    }
    clone() {
        return (new ThresholdScale).domain(this._domain).range(this._range).unknown(this._unknown);
    }
}