@dagrejs/dagre Documentation

The LayoutConfig interface allows for advanced customization of the layout engine execution.

Key properties:

• customOrder: A function to provide a custom ordering of nodes. It receives the graph and an order function.
• disableOptimalOrderHeuristic: Boolean to disable the optimal ordering heuristic.
• constraints: An array of OrderConstraint objects (e.g., { left: 'nodeA', right: 'nodeB' }) to enforce specific node ordering.

The GraphLabel interface defines the layout configuration for the entire graph. Use these properties to control direction, spacing, and ranking algorithms.

Key properties:

• rankdir: Direction of the graph ('TB' (top-to-bottom), 'BT' (bottom-to-top), 'LR' (left-to-right), or 'RL' (right-to-left)).
• nodesep: Separation between nodes.
• edgesep: Separation between edges.
• ranksep: Separation between ranks.
• compound: Boolean to enable/disable compound graph layout.
• ranker: The algorithm used to assign ranks ('network-simplex', 'tight-tree', or 'longest-path').
• acyclicer: Set to 'greedy' to enable the acyclic graph heuristic.

The layout function is the primary entry point for computing node and edge positions in a graph. It takes a Graph object and an optional LayoutOptions object. The function performs the layout calculations and updates the input graph with the computed coordinates (x, y), dimensions (width, height), and other layout-related attributes like rank, order, and points for edges.

Attributes updated in the input graph:

• Nodes: x, y, order, rank, and (if the node has children) width, height.
• Edges: points (array of coordinates), and (if the edge has an explicit position) x, y.
• Graph: width, height.

Layout Options:

• debugTiming: A boolean that, when true, enables timing instrumentation for the layout process steps.

The EdgeLabel interface contains properties used to describe and position edge labels and geometry.

Key properties include:

• points: An array of Point objects defining the edge path.
• width, height: Dimensions of the edge label.
• labelpos: Position of the label ('l', 'c', or 'r').
• reversed: Boolean indicating if the edge direction is reversed for labeling.

The NodeLabel interface contains the geometric and metadata properties used by the layout engine for each node. While many properties are used internally or by the engine to store results, they are part of the node's label definition.

Key properties include:

• width, height: Dimensions of the node.
• x, y: Calculated coordinates.
• rank: The rank assigned to the node.
• shape: The visual shape of the node.
• label: The text label for the node.
• padding, paddingX, paddingY: Spacing around the label.

The library exports several types for defining graph structures, layout configurations, and constraints. Use these for type-safe implementations of custom weight functions or rankers.

export type {
    GraphLabel,
    NodeConfig,
    EdgeConfig,
    LayoutConfig,
    LayoutOptions,
    NodeLabel,
    EdgeLabel,
    Point,
    OrderConstraint,
    WeightFunction,
    RankerFunction,
    Edge
} from './lib/types';