ConnectionLineType

Source on GitHub 

If you set the connectionLineType prop on your <ReactFlow /> component, it will dictate the style of connection line rendered when creating new edges.

export enum ConnectionLineType {
  Bezier = 'default',
  Straight = 'straight',
  Step = 'step',
  SmoothStep = 'smoothstep',
  SimpleBezier = 'simplebezier',
}

Notes

• If you choose to render a custom connection line component, this value will be passed to your component as part of its ConnectionLineComponentProps.