radius

Radius of rounded corners on orthogonal edges

type: double, default: 0, minimum: 0

Controls the radius of rounded corners on orthogonal edges. This attribute only has an effect when splines=ortho is set in the graph. When set to a value greater than 0, edge corners are rendered as smooth circular arcs instead of sharp 90-degree angles. The value specifies the radius of the arc in points. A value of 0 (default) produces square corners.

Available from Graphviz version ≥ 14.1.0.

Orthogonal Edges with Rounded Corners

digraph RoundedEdges {
  splines = ortho;
  nodesep = 1.0;
  ranksep = 1.0;

  // Default: square corners
  A -> X [xlabel="radius=0 (default)"];

  // Small rounded corners
  B -> X [radius=8, xlabel="radius=8", color=blue];

  // Medium rounded corners
  C -> X [radius=12, xlabel="radius=12", color=green];

  // Large rounded corners
  D -> X [radius=20, xlabel="radius=20", color=red];
}

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