Arc

4 min read

A built-in edge Arc has the default style as below.

Usage

As stated in Built-in Edges , there are three methods to configure edges: Configure edges globally when instantiating a Graph; Configure edges in their data; Configure edges by graph.edge(edgeFn). Their priorities are:

graph.edge(edgeFn) > Configure in data > Configure globally

⚠️ Attention: Expect for id, source, target, label which should be assigned to every single edge data, the other configurations in The Common Property and in each edge type (refer to doc of each edge type) support to be assigned by the three ways.

1 Global Configure When Instantiating a Graph

Assign type to 'arc' in the defaultEdge object when instantiating a Graph:

const graph = new G6.Graph({
  container: 'mountNode',
  width: 800,
  height: 600,
  defaultEdge: {
    type: 'arc', // The type of the edge
    // ...  Other configuraltions
  },
});

2 Configure in the Data

To configure different edges with different properties, you can write the properties into the edge data.

const data = {
  nodes: [
    ... // nodes
  ],
  edges: [{
    source: 'node0',
    target: 'node1'
    type: 'arc',
    //... // Other configurations for edges
    style: {
      //...  // Style properties for edges
    }
  },
    //... // Other edges
  ]
}

Property

Arc edge has the Common Edge Properties, and some commonly used properties are shown below, where curveOffset is the special property for arc edge , controlling the size and the bending direction of the arc.

color: '#87e8de',
curveOffset: 20,  // The distance between the center of the two endpoints and the center of the arc
style: {
  lineWidth: 2,
  stroke: '#87e8de'
},
label: 'Text of the label',
labelCfg: {
  refX: 10,  // x offset of the label
  refY: 10,  // y offset of the label
  style: {
    fill: '#595959'
  }
}

Name	Description	Type	Remark
color	The color of the edge	String	The priority id lower than `stroke` in `style`
curveOffset	The distance between the center of the two endpoints and the center of the arc	Number	The absolute value of `curveOffset` is the size of the arc, the sign of `curveOffset` is the bending direction of the arc. `20` by default. It is the special property for arc edge
style	The default style of edge	Object	Correspond to the styles in Canvas
label	The text of the label	String
labelCfg	The configurations of the label	Object
stateStyles	The styles in different states	Object	Refer to Configure Styles for State

Special Property: curveOffset

curveOffset is the special property for arc edge, which controlls the size and the bending direction of the arc. The following code shows how to configure the curveOffset globally when instantiating a Graph.

const data = {
  nodes: [
    {
      id: 'node0',
      x: 100,
      y: 100,
      size: 20,
    },
    {
      id: 'node1',
      x: 200,
      y: 200,
      size: 20,
    },
  ],
  edges: [
    {
      source: 'node0',
      target: 'node1',
      type: 'arc',
      label: 'arc',
    },
  ],
};
const graph = new G6.Graph({
  container: 'mountNode',
  width: 800,
  height: 600,
  linkCenter: true,
  defaultEdge: {
    // type: 'arc', // The type has been assigned in the data, we do not have to define it any more
    curveOffset: -80,
  },
});
graph.data(data);
graph.render();

⚠️Attention:
linkCenter: true is assigned to the graph in the code above to ensure the arc edges link to the center of their end nodes.

style

style is an object which is the same as the Common Edge Style Properties. Base on the code in curveOffset section, we add style to defaultEdge.
!

const data = {
  // ... data
};
const graph = new G6.Graph({
  // ... Other configurations for graph
  defaultEdge: {
    // ... Other properties for edges
    style: {
      stroke: '#088',
      lineWidth: 3,
    },
  },
});
// ...

labelCfg

labelCfg is an object which is the same as the Common Edge Label Properties. Base on the code in Special Property: curveOffset section, we add labelCfg to defaultEdge.

const data = {
  // ... data
};
const graph = new G6.Graph({
  // ... Other configurations for graph
  defaultEdge: {
    // ... Other properties for edges
    labelCfg: {
      autoRotate: true,
      refY: -30,
      refX: 30,
    },
  },
});
// ...