Function flattenDataDiffItems

src/animation/universalTransition.ts:119–144

(list: TransitionSeries[])

// flatten all data items from different serieses into one arrary
function flattenDataDiffItems(list: TransitionSeries[]) {
    const items: DiffItem[] = [];

    each(list, seriesInfo => {
        const data = seriesInfo.data;
        const dataGroupId = seriesInfo.dataGroupId;
        if (data.count() > DATA_COUNT_THRESHOLD) {
            if (__DEV__) {
                warn('Universal transition is disabled on large data > 10k.');
            }
            return;
        }
        const indices = data.getIndices();
        for (let dataIndex = 0; dataIndex < indices.length; dataIndex++) {
            items.push({
                data,
                groupId: getGroupId(data, dataIndex, dataGroupId, false), // either of groupId or childGroupId will be used as diffItem's key,
                childGroupId: getGroupId(data, dataIndex, dataGroupId, true),    // depending on the transition direction (see below)
                divide: seriesInfo.divide,
                dataIndex
            });
        }
    });

    return items;
}


function fadeInElement(newEl: Element, newSeries: SeriesModel, newIndex: number) {