text: define(function (require) {
      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 = edge.node1.getLayout();
              var p2 = edge.node2.getLayout();
              var cp1;
              if (curveness > 0) {
                  cp1 = [cx, cy];
              }
              edge.setLayout([p1, p2, cp1]);
          });
      };
  });