Function layout_tree 

pub fn layout_tree<T>(
    treeize: &Treeize<T>,
    config: LayoutConfig,
    has_output: impl FnMut(NodeId) -> bool,
    has_input: impl FnMut(NodeId) -> bool,
    node_sizes: Option<&HashMap<NodeId, Vec2>>,
) -> HashMap<NodeId, Pos2>

Performs hierarchical layout on a tree-like graph.

This function arranges nodes in a top-to-bottom tree structure using a compact contour-based layout algorithm (similar to ELK Mr.Tree). Nodes are organized into levels based on their distance from root nodes.

Arguments

• treeize - The tree graph to layout
• config - Layout configuration parameters
• has_output - Function to check if a node has output pins
• has_input - Function to check if a node has input pins
• node_sizes - Optional map from node ID to node size (width, height). If provided, the layout will consider actual node sizes to avoid overlaps.

Returns

A map from node ID to its calculated position (top-left corner).

Panics

This function does not panic, but may produce unexpected layouts if the graph contains cycles or if node sizes are invalid.