source/Repid.MvcApplication/Content/utility/highcharts/js/modules/boost.src.js

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/**
 * This is an experimental Highcharts module that draws long data series on a canvas
 * in order to increase performance of the initial load time and tooltip responsiveness.
 *
 * Compatible with HTML5 canvas compatible browsers (not IE < 9).
 *
 * Author: Torstein Honsi
 *
 * 
 * Development plan
 * - Column range.
 * - Heatmap.
 * - Treemap.
 * - Check how it works with Highstock and data grouping. Currently it only works when navigator.adaptToUpdatedData
 *   is false. It is also recommended to set scrollbar.liveRedraw to false.
 * - Check inverted charts.
 * - Check reversed axes.
 * - Chart callback should be async after last series is drawn. (But not necessarily, we don't do
     that with initial series animation).
 * - Cache full-size image so we don't have to redraw on hide/show and zoom up. But k-d-tree still
 *   needs to be built.
 * - Test IE9 and IE10.
 * - Stacking is not perhaps not correct since it doesn't use the translation given in 
 *   the translate method. If this gets to complicated, a possible way out would be to 
 *   have a simplified renderCanvas method that simply draws the areaPath on a canvas.
 *
 * If this module is taken in as part of the core
 * - All the loading logic should be merged with core. Update styles in the core.
 * - Most of the method wraps should probably be added directly in parent methods.
 *
 * Notes for boost mode
 * - Area lines are not drawn
 * - Point markers are not drawn on line-type series
 * - Lines are not drawn on scatter charts
 * - Zones and negativeColor don't work
 * - Columns are always one pixel wide. Don't set the threshold too low.
 *
 * Optimizing tips for users
 * - For scatter plots, use a marker.radius of 1 or less. It results in a rectangle being drawn, which is 
 *   considerably faster than a circle.
 * - Set extremes (min, max) explicitly on the axes in order for Highcharts to avoid computing extremes.
 * - Set enableMouseTracking to false on the series to improve total rendering time.
 * - The default threshold is set based on one series. If you have multiple, dense series, the combined
 *   number of points drawn gets higher, and you may want to set the threshold lower in order to 
 *   use optimizations.
 */

/* eslint indent: [2, 4] */
(function (factory) {
    if (typeof module === 'object' && module.exports) {
        module.exports = factory;
    } else {
        factory(Highcharts);
    }
}(function (H) {

    'use strict';

    var win = H.win,
        doc = win.document,