Returns the target frame rate.

Activates the first unactivated rollover in the group. Has no effect if all are active.

Returns true if all targets have been hit (and their corresponding bodies made inactive)

Checks whether the ball appears to be stuck, and nudges it if so.

Must be overridden by subclasses, to create the element's Box2D bodies. This will be called after finishCreateElement has completed (without throwing

Creates and returns a FieldElement object from the given map of parameters. The class to instantiate is given by the "class" property of the parameter

Returns the current frames per second, based on previously recorded frame times. If there have not been a sufficient number of times recorded, returns

Cycles the states of all rollover elements by "rotating" left or right. For example, if this group has three rollovers whose states are (on, on, off),

Called when a ball has ended. Ends the game if that was the last ball, otherwise updates GameState to the next ball. Shows a game message to indicate

Ends a game in progress by removing all balls in play, calling setGameInProgress(false) on the GameState, and setting a "Game Over" message for displa

Must be overridden by subclasses, which should perform any setup required after creation. Throws DependencyNotAvailableException if the element can't

Returns a String with debugging info, including current frame rate, target rate, and whether the rate is locked.

Records the given frame start time in nanoseconds. Normally clients will call the no-argument frameStarted(), which calls this method with System.nano