Package org.jungrapht.visualization.layout.algorithms

Class FRLayoutAlgorithm<V>

  • All Implemented Interfaces:
    IterativeLayoutAlgorithm<V>, LayoutAlgorithm<V>, AfterRunnable, ExecutorConsumer, IterativeContext, Threaded
    public class FRLayoutAlgorithm<V>
extends AbstractIterativeLayoutAlgorithm<V>
implements IterativeContext
    Implements the Fruchterman-Reingold force-directed algorithm for vertex layout.

    Behavior is determined by the following settable parameters:

    • attraction multiplier: how much edges try to keep their vertices together
    • repulsion multiplier: how much vertices try to push each other apart
    • maximum iterations: how many iterations this algorithm will use before stopping
    Each of the first two defaults to 0.75; the maximum number of iterations defaults to 700.
    Author:
    Scott White, Yan-Biao Boey, Danyel Fisher, Tom Nelson
    See Also:
    "Fruchterman and Reingold, 'Graph Drawing by Force-directed Placement'", "http://i11www.ilkd.uni-karlsruhe.de/teaching/SS_04/visualisierung/papers/fruchterman91graph.pdf"

    • Field Detail

      • frVertexData

        protected Map<V,​Point> frVertexData

      • attractionConstant

        protected double attractionConstant

      • repulsionConstant

        protected double repulsionConstant

      • EPSILON

        protected double EPSILON

    • Constructor Detail

      • FRLayoutAlgorithm

        public FRLayoutAlgorithm()

    • Method Detail

      • visit

        public void visit​(LayoutModel<V> layoutModel)
        Description copied from class: AbstractIterativeLayoutAlgorithm
        because the IterativeLayoutAlgorithms use multithreading to continuously update vertex positions, the layoutModel state is saved (during the visit method) so that it can be used continuously
        Specified by:
        visit in interface LayoutAlgorithm<V>
        Overrides:
        visit in class AbstractIterativeLayoutAlgorithm<V>
        Parameters:
        layoutModel - the mediator between the container for vertices (the Graph) and the mapping from Vertex to Point

      • setAttractionMultiplier

        public void setAttractionMultiplier​(double attraction)

      • setRepulsionMultiplier

        public void setRepulsionMultiplier​(double repulsion)

      • initialize

        public void initialize()

      • step

        public void step()
        Moves the iteration forward one notch, calculation attraction and repulsion between vertices and edges and cooling the temperature.
        Specified by:
        step in interface IterativeContext

      • calcPositions

        protected void calcPositions​(V vertex)

      • calcAttraction

        protected void calcAttraction​(Object edge)

      • setMaxIterations

        public void setMaxIterations​(int maxIterations)

      • getFRData

        protected Point getFRData​(V vertex)

      • done

        public boolean done()
        Specified by:
        done in interface IterativeContext
        Returns:
        true once the current iteration has passed the maximum count.