Class SpringLayoutAlgorithm

java.lang.Object
org.eclipse.gef.layout.algorithms.SpringLayoutAlgorithm
All Implemented Interfaces:
ILayoutAlgorithm

public class SpringLayoutAlgorithm extends Object implements ILayoutAlgorithm
The SpringLayoutAlgorithm has its own data repository and relation repository. A user can populate the repository, specify the layout conditions, do the computation and query the computed results.
  • Constructor Details

    • SpringLayoutAlgorithm

      public SpringLayoutAlgorithm()
  • Method Details

    • applyLayout

      public void applyLayout(LayoutContext layoutContext, boolean clean)
      Description copied from interface: ILayoutAlgorithm
      Makes this algorithm perform layout computation and apply it to its context.
      Specified by:
      applyLayout in interface ILayoutAlgorithm
      Parameters:
      layoutContext - The LayoutContext that provides all relevant information about what to layout.
      clean - if true the receiver should assume that the layout context has changed significantly and recompute the whole layout even if it keeps track of changes with listeners. False can be used after dynamic layout in a context is turned back on so that layout algorithm working in background can apply accumulated changes. Static layout algorithm can ignore this call entirely if clean is false.
    • performNIteration

      public void performNIteration(int n)
      Performs the given number of iterations.
      Parameters:
      n - The number of iterations to perform.
    • performOneIteration

      public void performOneIteration()
      Performs one single iteration.
    • isResizing

      public boolean isResizing()
      Returns:
      true if this algorithm is set to resize elements
    • setResizing

      public void setResizing(boolean resizing)
      Parameters:
      resizing - true if this algorithm should resize elements (default is false)
    • setSpringMove

      public void setSpringMove(double move)
      Sets the spring layout move-control.
      Parameters:
      move - The move-control value.
    • getSpringMove

      public double getSpringMove()
      Returns the move-control value of this SpringLayoutAlgorithm in double precision.
      Returns:
      The move-control value.
    • setSpringStrain

      public void setSpringStrain(double strain)
      Sets the spring layout strain-control.
      Parameters:
      strain - The strain-control value.
    • getSpringStrain

      public double getSpringStrain()
      Returns the strain-control value of this SpringLayoutAlgorithm in double precision.
      Returns:
      The strain-control value.
    • setSpringLength

      public void setSpringLength(double length)
      Sets the spring layout length-control.
      Parameters:
      length - The length-control value.
    • getSpringTimeout

      public long getSpringTimeout()
      Gets the max time this algorithm will run for
      Returns:
      the timeout up to which this algorithm may run
    • setSpringTimeout

      public void setSpringTimeout(long timeout)
      Sets the spring timeout to the given value (in millis).
      Parameters:
      timeout - The new spring timeout (in millis).
    • getSpringLength

      public double getSpringLength()
      Returns the length-control value of this SpringLayoutAlgorithm in double precision.
      Returns:
      The length-control value.
    • setSpringGravitation

      public void setSpringGravitation(double gravitation)
      Sets the spring layout gravitation-control.
      Parameters:
      gravitation - The gravitation-control value.
    • getSpringGravitation

      public double getSpringGravitation()
      Returns the gravitation-control value of this SpringLayoutAlgorithm in double precision.
      Returns:
      The gravitation-control value.
    • setIterations

      public void setIterations(int iterations)
      Sets the number of iterations to be used.
      Parameters:
      iterations - The number of iterations.
    • getIterations

      public int getIterations()
      Returns the number of iterations to be used.
      Returns:
      The number of iterations.
    • setRandom

      public void setRandom(boolean random)
      Sets whether or not this SpringLayoutAlgorithm will layout the nodes randomly before beginning iterations.
      Parameters:
      random - The random placement value.
    • getRandom

      public boolean getRandom()
      Returns whether or not this SpringLayoutAlgorithm will layout the nodes randomly before beginning iterations.
      Returns:
      true if this algorithm will layout the nodes randomly before iterating, otherwise false.
    • performAnotherNonContinuousIteration

      protected boolean performAnotherNonContinuousIteration()
      Performs one iteration based on time.
      Returns:
      true if the maximum number of iterations was not reached yet, otherwise false.
    • getCurrentLayoutStep

      protected int getCurrentLayoutStep()
      Returns the current iteration.
      Returns:
      The current iteration.
    • getTotalNumberOfLayoutSteps

      protected int getTotalNumberOfLayoutSteps()
      Returns the maximum number of iterations.
      Returns:
      The maximum number of iterations.
    • computeOneIteration

      protected void computeOneIteration()
      Computes one iteration (forces, positions) and increases the iteration counter.
    • placeRandomly

      protected void placeRandomly()
      Puts vertices in random places, all between (0,0) and (1,1).
    • computeForces

      protected void computeForces()
      Computes the force for each node in this SpringLayoutAlgorithm. The computed force will be stored in the data repository
    • computePositions

      protected void computePositions()
      Computes the position for each node in this SpringLayoutAlgorithm. The computed position will be stored in the data repository. position = position + sprMove * force