update()

in showcases/graph/graph-layer/layout/layout-d3.js [19:85]

• 60 lines of code
• 7 McCabe index (conditional complexity)

  update(data, layoutProps) {
    const {alphaOnDataChange, alphaOnDrag} = this.props;
    if (this._simulation && data) {
      // If new data are passed, update the simulation with the new data
      this._simulation
        .nodes(data.nodes)
        .force(
          'link',
          forceLink(data.links)
            .id(n => n.id)
            .strength(this.props.linkStrength)
            .distance(this.props.linkDistance)
        )
        .alpha(alphaOnDataChange);
    } else if (!this._simulation) {
      if (data) {
        // Instantiate the simulation with the passed data
        const {nBodyStrength, nBodyDistanceMin, nBodyDistanceMax} = this.props;
        this._simulation = forceSimulation(data.nodes)
          .force(
            'link',
            forceLink(data.links)
              .id(n => n.id)
              .strength(this.props.linkStrength)
              .distance(this.props.linkDistance)
          )
          .force(
            'charge',
            forceManyBody()
              .strength(nBodyStrength)
              .distanceMin(nBodyDistanceMin)
              .distanceMax(nBodyDistanceMax)
          )
          .force('center', forceCenter())
          .stop();
      } else {
        // No data passed and simulation has not yet been instantiated,
        // so return empty object.
        return {
          nodes: [],
          isUpdating: false
        };
      }
    }

    const {fixedNodes, unfixedNodes} = layoutProps;
    if (fixedNodes) {
      fixedNodes.forEach(n => {
        n.node.fx = n.x;
        n.node.fy = n.y;
      });
      this._reheat(alphaOnDrag);
    }
    if (unfixedNodes) {
      unfixedNodes.forEach(n => {
        n.node.fx = null;
        n.node.fy = null;
      });
    }

    // Process one simulation tick and return results.
    this._simulation.tick();
    return {
      nodes: this._simulation.nodes(),
      isUpdating: this.isUpdating()
    };
  }