Function extractScale

src/components/colorscale/helpers.js:115–135

* Extract colorscale into numeric domain and color range. * * @param {object} cont colorscale container (e.g. trace, marker) * - colorscale {array of arrays} * - cmin/zmin {number} * - cmax/zmax {number} * - reversescale {boolean} * * @return {object} * - domain {array} * - range {ar

(cont)

 *  - range {array}
 */
function extractScale(cont) {
    var cOpts = extractOpts(cont);
    var cmin = cOpts.min;
    var cmax = cOpts.max;

    var scl = cOpts.reversescale ?
        flipScale(cOpts.colorscale) :
        cOpts.colorscale;

    var N = scl.length;
    var domain = new Array(N);
    var range = new Array(N);

    for(var i = 0; i < N; i++) {
        var si = scl[i];
        domain[i] = cmin + si[0] * (cmax - cmin);
        range[i] = si[1];
    }

    return {domain: domain, range: range};
}

function flipScale(scl) {
    var N = scl.length;