Function brushVisual

src/component/brush/visualEncoding.ts:73–239

* Register the visual encoding if this modules required.

(ecModel: GlobalModel, api: ExtensionAPI, payload: Payload)

 * Register the visual encoding if this modules required.
 */
function brushVisual(ecModel: GlobalModel, api: ExtensionAPI, payload: Payload) {

    const brushSelected: BrushSelectedItem[] = [];
    let throttleType;
    let throttleDelay;

    ecModel.eachComponent({mainType: 'brush'}, function (brushModel: BrushModel) {
        payload && payload.type === 'takeGlobalCursor' && brushModel.setBrushOption(
            payload.key === 'brush' ? payload.brushOption : {brushType: false}
        );
    });

    layoutCovers(ecModel);


    ecModel.eachComponent({mainType: 'brush'}, function (brushModel: BrushModel, brushIndex) {

        const thisBrushSelected: BrushSelectedItem = {
            brushId: brushModel.id,
            brushIndex: brushIndex,
            brushName: brushModel.name,
            areas: zrUtil.clone(brushModel.areas),
            selected: []
        };
        // Every brush component exists in event params, convenient
        // for user to find by index.
        brushSelected.push(thisBrushSelected);

        const brushOption = brushModel.option;
        const brushLink = brushOption.brushLink;
        const linkedSeriesMap: {[seriesIndex: number]: 0 | 1} = [];
        const selectedDataIndexForLink: {[dataIndex: number]: 0 | 1} = [];
        const rangeInfoBySeries: {[seriesIndex: number]: BrushSelectableArea[]} = [];
        let hasBrushExists = false;

        if (!brushIndex) { // Only the first throttle setting works.
            throttleType = brushOption.throttleType;
            throttleDelay = brushOption.throttleDelay;
        }

        // Add boundingRect and selectors to range.
        const areas: BrushSelectableArea[] = zrUtil.map(brushModel.areas, function (area) {
            const builder = boundingRectBuilders[area.brushType];
            const selectableArea = zrUtil.defaults(
                {boundingRect: builder ? builder(area) : void 0},
                area
            ) as BrushSelectableArea;
            selectableArea.selectors = makeBrushCommonSelectorForSeries(selectableArea);
            return selectableArea;
        });

        const visualMappings = visualSolution.createVisualMappings(
            brushModel.option, STATE_LIST, function (mappingOption) {
                mappingOption.mappingMethod = 'fixed';
            }
        );

        zrUtil.isArray(brushLink) && zrUtil.each(brushLink, function (seriesIndex) {