Function createCurveness

src/chart/helper/multipleGraphEdgeHelper.ts:39–66

(seriesModel, appendLength)

 * @return  20 => [0, -0.2, 0.2, -0.4, 0.4, -0.6, 0.6, -0.8, 0.8, -1, 1, -1.2, 1.2, -1.4, 1.4, -1.6, 1.6, -1.8, 1.8, -2]
 */
const createCurveness = function (seriesModel, appendLength) {
    const autoCurvenessParmas = getAutoCurvenessParams(seriesModel);
    let length = 20;
    let curvenessList = [];

    // handler the function set
    if (zrUtil.isNumber(autoCurvenessParmas)) {
        length = autoCurvenessParmas;
    }
    else if (zrUtil.isArray(autoCurvenessParmas)) {
        seriesModel.__curvenessList = autoCurvenessParmas;
        return;
    }

    // append length
    if (appendLength > length) {
        length = appendLength;
    }

    // make sure the length is even
    const len = length % 2 ? length + 2 : length + 3;
    curvenessList = [];

    for (let i = 0; i < len; i++) {
        curvenessList.push((i % 2 ? i + 1 : i) / 10 * (i % 2 ? -1 : 1));
    }
    seriesModel.__curvenessList = curvenessList;
};

/**
 * Create different cache key data in the positive and negative directions, in order to set the curvature later