Package edu.umd.cs.piccolo.activities

Class PInterpolatingActivity

java.lang.Object
edu.umd.cs.piccolo.activities.PActivity
edu.umd.cs.piccolo.activities.PInterpolatingActivity
Direct Known Subclasses:
PColorActivity, PTransformActivity
public class PInterpolatingActivity extends PActivity
PInterpolatingActivity interpolates between two states (source and destination) over the duration of the activity. The interpolation can be either linear or slow- in, slow-out.

The mode determines how the activity interpolates between the two states. The default mode interpolates from source to destination, but you can also go from destination to source, and from source to destination to source.

A loopCount of greater then one will make the activity reschedule itself when it has finished. This makes the activity loop between the two states.

Version:
1.0
Author:
Jesse Grosjean

  • Field Details

    • SOURCE_TO_DESTINATION

      public static final int SOURCE_TO_DESTINATION
      Specifies that interpolation will be from the source value to the destination value.
      See Also:

    • DESTINATION_TO_SOURCE

      public static final int DESTINATION_TO_SOURCE
      Specifies that interpolation will be from the destination value to the source value.
      See Also:

    • SOURCE_TO_DESTINATION_TO_SOURCE

      public static final int SOURCE_TO_DESTINATION_TO_SOURCE
      Specifies that interpolation proceed from the source to the destination then back to the source. Can be used to perform flashes. source value.
      See Also:

  • Constructor Details

    • PInterpolatingActivity

      public PInterpolatingActivity(long duration)
      Constructs an interpolating activity that will last the duration given.
      Parameters:
      duration - duration in milliseconds of the entire activity
      Since:
      1.3

    • PInterpolatingActivity

      public PInterpolatingActivity(long duration, long stepRate)
      Constructs an interpolating activity that will last the duration given and will update its target at the given rate.
      Parameters:
      duration - duration in milliseconds of the entire activity
      stepRate - interval in milliseconds between updates to target

    • PInterpolatingActivity

      public PInterpolatingActivity(long duration, long stepRate, int loopCount, int mode)
      Constructs an interpolating activity that will last the duration given and will update its target at the given rate. Once done, it will repeat the loopCount times.
      Parameters:
      duration - duration in milliseconds of the entire activity
      stepRate - interval in milliseconds between updates to target
      loopCount - # of times to repeat this activity.
      mode - controls the direction of the interpolation (source to destination, destination to source, or source to destination back to source)

    • PInterpolatingActivity

      public PInterpolatingActivity(long duration, long stepRate, long startTime, int loopCount, int mode)
      Create a new PInterpolatingActivity.

      Parameters:
      duration - the length of one loop of the activity
      stepRate - the amount of time between steps of the activity
      startTime - the time (relative to System.currentTimeMillis()) that this activity should start. This value can be in the future.
      loopCount - number of times the activity should reschedule itself
      mode - defines how the activity interpolates between states

  • Method Details

    • setDuration

      public void setDuration(long duration)
      Set the amount of time that this activity should take to complete, after the startStepping method is called. The duration must be greater then zero so that the interpolation value can be computed.
      Overrides:
      setDuration in class PActivity
      Parameters:
      duration - new duration of this activity

    • getMode

      public int getMode()
      Return the mode used for interpolation. Acceptable values are: SOURCE_TO_DESTINATION, DESTINATION_TO_SOURCE and SOURCE_TO_DESTINATION_TO_SOURCE
      Returns:
      current mode of this activity

    • setMode

      public void setMode(int mode)
      Set the direction in which interpolation is going to occur. Acceptable values are: SOURCE_TO_DESTINATION, DESTINATION_TO_SOURCE and SOURCE_TO_DESTINATION_TO_SOURCE
      Parameters:
      mode - the new mode to use when interpolating

    • getLoopCount

      public int getLoopCount()
      Return the number of times the activity should automatically reschedule itself after it has finished.
      Returns:
      number of times to repeat this activity

    • setLoopCount

      public void setLoopCount(int loopCount)
      Set the number of times the activity should automatically reschedule itself after it has finished.
      Parameters:
      loopCount - number of times to repeat this activity

    • getFirstLoop

      public boolean getFirstLoop()
      Return true if the activity is executing its first loop. Subclasses normally initialize their source state on the first loop.
      Returns:
      true if executing first loop

    • setFirstLoop

      public void setFirstLoop(boolean firstLoop)
      Set if the activity is executing its first loop. Subclasses normally initialize their source state on the first loop. This method will rarely need to be called, unless your are reusing activities.
      Parameters:
      firstLoop - true if executing first loop

    • getSlowInSlowOut

      public boolean getSlowInSlowOut()
      Returns whether this interpolation accelerates and then decelerates as it interpolates.
      Returns:
      true if accelerations are being applied apply

    • setSlowInSlowOut

      public void setSlowInSlowOut(boolean isSlowInSlowOut)
      Sets whether this interpolation accelerates and then decelerates as it interpolates.
      Parameters:
      isSlowInSlowOut - true if this interpolation inovolves some accelerations

    • activityStarted

      protected void activityStarted()
      Called when activity is started. Makes sure target value is set properly for start of activity.
      Overrides:
      activityStarted in class PActivity

    • activityStep

      protected void activityStep(long elapsedTime)
      Called at each step of the activity. Sets the current position taking mode into account.
      Overrides:
      activityStep in class PActivity
      Parameters:
      elapsedTime - number of milliseconds since the activity began

    • activityFinished

      protected void activityFinished()
      Called whenever the activity finishes. Reschedules it if the value of loopCount is > 0.
      Overrides:
      activityFinished in class PActivity

    • terminate

      public void terminate()
      Stop this activity immediately, and remove it from the activity scheduler. If this activity is currently running then stoppedStepping will be called after it has been removed from the activity scheduler.
      Overrides:
      terminate in class PActivity

    • setRelativeTargetValue

      public void setRelativeTargetValue(float zeroToOne)
      Subclasses should override this method and set the value on their target (the object that they are modifying) accordingly.
      Parameters:
      zeroToOne - relative completion of task.

    • computeSlowInSlowOut

      public float computeSlowInSlowOut(float zeroToOne)
      Computes percent or linear interpolation to apply when taking acceleration into account.
      Parameters:
      zeroToOne - Percentage of activity completed
      Returns:
      strength of acceleration

    • setRelativeTargetValueAdjustingForMode

      protected void setRelativeTargetValueAdjustingForMode(float zeroToOne)
      Assigns relative target value taking the mode into account.
      Parameters:
      zeroToOne - Percentage of activity completed