LiveFlow.Paths.Path behaviour (LiveFlow v0.4.0)

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Behaviour for edge path calculations.

Path modules calculate SVG path strings for rendering edges between nodes. Each path type (bezier, straight, step, smoothstep) implements this behaviour.

Path Result

The calculate/2 function returns a map with:

  • :path - SVG path string (e.g., "M0,0 C50,0 50,100 100,100")
  • :label_x - X coordinate for edge label
  • :label_y - Y coordinate for edge label

Implementing a Custom Path

defmodule MyApp.CustomPath do
  @behaviour LiveFlow.Paths.Path

  @impl true
  def calculate(source, target, opts) do
    # Custom path calculation
    %{
      path: "M ...",
      label_x: ...,
      label_y: ...
    }
  end
end

Summary

Types

point()

Source/target point with position information.

result()

Path calculation result.

Callbacks

calculate(source, target, opts)

Calculates the SVG path between source and target points.

Functions

calculate(module, source, target, opts \\ [])

Calculates a path using the specified path module.

module_for_type(arg1)

Gets the path module for an edge type.

Types

point()

@type point() :: %{
  x: number(),
  y: number(),
  position: :top | :bottom | :left | :right
}

Source/target point with position information.

  • :x - X coordinate
  • :y - Y coordinate
  • :position - Handle position (:top, :bottom, :left, :right)

result()

@type result() :: %{path: String.t(), label_x: number(), label_y: number()}

Path calculation result.

Callbacks

calculate(source, target, opts)

@callback calculate(source :: point(), target :: point(), opts :: keyword()) :: result()

Calculates the SVG path between source and target points.

Options

Options are path-type specific. Common options include:

  • :curvature - Curve intensity (0.0 to 1.0)
  • :offset - Distance from node before turning
  • :border_radius - Corner rounding for step paths

Functions

calculate(module, source, target, opts \\ [])

@spec calculate(module(), point(), point(), keyword()) :: result()

Calculates a path using the specified path module.

module_for_type(arg1)

@spec module_for_type(atom()) :: module()

Gets the path module for an edge type.