Class: Gdk::FrameClock

Inherits:
Object
  • Object
show all
Defined in:
(unknown)

Instance Method Summary collapse

Instance Method Details

#begin_updatingnil

Starts updates for an animation.

Until a matching call to [methodGdk.FrameClock.end_updating] is made, the frame clock will continually request a new frame with the %GDK_FRAME_CLOCK_PHASE_UPDATE phase. This function may be called multiple times and frames will be requested until gdk_frame_clock_end_updating() is called the same number of times.

Returns:

  • (nil)

#current_timingsGdk::FrameTimings

Gets the frame timings for the current frame.

Returns:

  • (Gdk::FrameTimings)

    the GdkFrameTimings for the frame currently being processed, or even no frame is being processed, for the previous frame. Before any frames have been processed, returns nil.

#end_updatingnil

Stops updates for an animation.

See the documentation for [methodGdk.FrameClock.begin_updating].

Returns:

  • (nil)

#fpsFloat

Calculates the current frames-per-second, based on the frame timings of frame_clock.

Returns:

  • (Float)

    the current fps, as a double

#frame_counterInteger

GdkFrameClock maintains a 64-bit counter that increments for each frame drawn.

Returns:

  • (Integer)

    inside frame processing, the value of the frame counter for the current frame. Outside of frame processing, the frame counter for the last frame.

#frame_timeInteger

Gets the time that should currently be used for animations.

Inside the processing of a frame, it’s the time used to compute the animation position of everything in a frame. Outside of a frame, it's the time of the conceptual “previous frame,” which may be either the actual previous frame time, or if that’s too old, an updated time.

Returns:

  • (Integer)

    a timestamp in microseconds, in the timescale of of g_get_monotonic_time().

#get_refresh_info(base_time, refresh_interval_return, presentation_time_return) ⇒ nil

Predicts a presentation time, based on history.

Using the frame history stored in the frame clock, finds the last known presentation time and refresh interval, and assuming that presentation times are separated by the refresh interval, predicts a presentation time that is a multiple of the refresh interval after the last presentation time, and later than base_time.

Parameters:

  • base_time (Integer)

    base time for determining a presentaton time

  • refresh_interval_return (Integer)

    a location to store the determined refresh interval, or nil. A default refresh interval of 1/60th of a second will be stored if no history is present.

  • presentation_time_return (Integer)

    a location to store the next candidate presentation time after the given base time. 0 will be will be stored if no history is present.

Returns:

  • (nil)

#get_timings(frame_counter) ⇒ Gdk::FrameTimings

Retrieves a GdkFrameTimings object holding timing information for the current frame or a recent frame.

The GdkFrameTimings object may not yet be complete: see [methodGdk.FrameTimings.get_complete] and [methodGdk.FrameClock.get_history_start].

Parameters:

  • frame_counter (Integer)

    the frame counter value identifying the frame to be received

Returns:

  • (Gdk::FrameTimings)

    the GdkFrameTimings object for the specified frame, or nil if it is not available

#history_startInteger

Returns the frame counter for the oldest frame available in history.

GdkFrameClock internally keeps a history of GdkFrameTimings objects for recent frames that can be retrieved with [methodGdk.FrameClock.get_timings]. The set of stored frames is the set from the counter values given by [methodGdk.FrameClock.get_history_start] and [methodGdk.FrameClock.get_frame_counter], inclusive.

Returns:

  • (Integer)

    the frame counter value for the oldest frame that is available in the internal frame history of the GdkFrameClock

#request_phase(phase) ⇒ nil

Asks the frame clock to run a particular phase.

The signal corresponding the requested phase will be emitted the next time the frame clock processes. Multiple calls to gdk_frame_clock_request_phase() will be combined together and only one frame processed. If you are displaying animated content and want to continually request the %GDK_FRAME_CLOCK_PHASE_UPDATE phase for a period of time, you should use [methodGdk.FrameClock.begin_updating] instead, since this allows GTK to adjust system parameters to get maximally smooth animations.

Parameters:

Returns:

  • (nil)