Combined DAG legend key (horizontal node-edge-node) — draw_key_dag

A custom legend key function that displays a complete DAG representation showing two nodes connected by an arrow. This provides a unified legend entry for plots that show both nodes and edges.

Usage

draw_key_dag_combined(data, params, size)

Arguments

data: A data frame containing aesthetic information for the legend key
params: Additional parameters (not currently used)
size: Legend key size (not currently used)

Value

A grob object for the legend key