Struct

GdkFrameTimings

Description [src]

struct GdkFrameTimings {
  /* No available fields */
}

A GdkFrameTimings object holds timing information for a single frame of the application’s displays. To retrieve GdkFrameTimings objects, use gdk_frame_clock_get_timings() or gdk_frame_clock_get_current_timings(). The information in GdkFrameTimings is useful for precise synchronization of video with the event or audio streams, and for measuring quality metrics for the application’s display, such as latency and jitter.

Instance methods

gdk_frame_timings_get_complete

The timing information in a GdkFrameTimings is filled in incrementally as the frame as drawn and passed off to the window system for processing and display to the user. The accessor functions for GdkFrameTimings can return 0 to indicate an unavailable value for two reasons: either because the information is not yet available, or because it isn’t available at all. Once gdk_frame_timings_get_complete() returns TRUE for a frame, you can be certain that no further values will become available and be stored in the GdkFrameTimings.

Available since: 3.8

gdk_frame_timings_get_frame_counter

Gets the frame counter value of the GdkFrameClock when this this frame was drawn.

Available since: 3.8

gdk_frame_timings_get_frame_time

Returns the frame time for the frame. This is the time value that is typically used to time animations for the frame. See gdk_frame_clock_get_frame_time().

gdk_frame_timings_get_predicted_presentation_time

Gets the predicted time at which this frame will be displayed. Although no predicted time may be available, if one is available, it will be available while the frame is being generated, in contrast to gdk_frame_timings_get_presentation_time(), which is only available after the frame has been presented. In general, if you are simply animating, you should use gdk_frame_clock_get_frame_time() rather than this function, but this function is useful for applications that want exact control over latency. For example, a movie player may want this information for Audio/Video synchronization.

Available since: 3.8

gdk_frame_timings_get_presentation_time

Reurns the presentation time. This is the time at which the frame became visible to the user.

Available since: 3.8

gdk_frame_timings_get_refresh_interval

Gets the natural interval between presentation times for the display that this frame was displayed on. Frame presentation usually happens during the “vertical blanking interval”.

Available since: 3.8

gdk_frame_timings_ref

Increases the reference count of timings.

Available since: 3.8

gdk_frame_timings_unref

Decreases the reference count of timings. If timings is no longer referenced, it will be freed.

Available since: 3.8