File: vendors/gentelella/vendors/echarts/src/chart/graph/circularLayoutHelper.js

define(function (require) {
    var vec2 = require('zrender/core/vector');
    return function (seriesModel) {
        var coordSys = seriesModel.coordinateSystem;
        if (coordSys && coordSys.type !== 'view') {
            return;
        }

        var rect = coordSys.getBoundingRect();

        var nodeData = seriesModel.getData();
        var graph = nodeData.graph;

        var angle = 0;
        var sum = nodeData.getSum('value');
        var unitAngle = Math.PI * 2 / (sum || nodeData.count());

        var cx = rect.width / 2 + rect.x;
        var cy = rect.height / 2 + rect.y;

        var r = Math.min(rect.width, rect.height) / 2;

        graph.eachNode(function (node) {
            var value = node.getValue('value');

            angle += unitAngle * (sum ? value : 2) / 2;

            node.setLayout([
                r * Math.cos(angle) + cx,
                r * Math.sin(angle) + cy
            ]);

            angle += unitAngle * (sum ? value : 2) / 2;
        });

        graph.eachEdge(function (edge) {
            var curveness = edge.getModel().get('lineStyle.normal.curveness') || 0;
            var p1 = vec2.clone(edge.node1.getLayout());
            var p2 = vec2.clone(edge.node2.getLayout());
            var cp1;
            var x12 = (p1[0] + p2[0]) / 2;
            var y12 = (p1[1] + p2[1]) / 2;
            if (curveness > 0) {
                curveness *= 3;
                cp1 = [
                    cx * curveness + x12 * (1 - curveness),
                    cy * curveness + y12 * (1 - curveness)
                ];
            }
            edge.setLayout([p1, p2, cp1]);
        });
    };
});