medical/node_modules/echarts/lib/chart/graph/simpleLayoutHelper.js

var vec2 = require("zrender/lib/core/vector");

function simpleLayout(seriesModel) {
  var coordSys = seriesModel.coordinateSystem;

  if (coordSys && coordSys.type !== 'view') {
    return;
  }

  var graph = seriesModel.getGraph();
  graph.eachNode(function (node) {
    var model = node.getModel();
    node.setLayout([+model.get('x'), +model.get('y')]);
  });
  simpleLayoutEdge(graph);
}

function simpleLayoutEdge(graph) {
  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 points = [p1, p2];

    if (+curveness) {
      points.push([(p1[0] + p2[0]) / 2 - (p1[1] - p2[1]) * curveness, (p1[1] + p2[1]) / 2 - (p2[0] - p1[0]) * curveness]);
    }

    edge.setLayout(points);
  });
}

exports.simpleLayout = simpleLayout;
exports.simpleLayoutEdge = simpleLayoutEdge;