Class FrameTimings
- All Implemented Interfaces:
Proxy
GdkFrameTimings
object holds timing information for a single frame
of the application’s displays.
To retrieve GdkFrameTimings
objects, use FrameClock.getTimings(long)
or FrameClock.getCurrentTimings()
. 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.
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Constructor Summary
ConstructorDescriptionFrameTimings
(MemorySegment address) Create a FrameTimings proxy instance for the provided memory address. -
Method Summary
Modifier and TypeMethodDescriptionboolean
Returns whether this FrameTimings are complete.long
Gets the frame counter value of theGdkFrameClock
when this frame was drawn.long
Returns the frame time for the frame.long
Gets the predicted time at which this frame will be displayed.long
Reurns the presentation time.long
Gets the natural interval between presentation times for the display that this frame was displayed on.static Type
getType()
Get the GType of the FrameTimings classref()
Increases the reference count of this FrameTimings.void
unref()
Decreases the reference count of this FrameTimings.Methods inherited from class io.github.jwharm.javagi.base.ProxyInstance
equals, handle, hashCode
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Constructor Details
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FrameTimings
Create a FrameTimings proxy instance for the provided memory address.- Parameters:
address
- the memory address of the native object
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Method Details
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getType
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getComplete
public boolean getComplete()Returns whether this FrameTimings are 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 forGdkFrameTimings
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 this function returns
true
for a frame, you can be certain that no further values will become available and be stored in theGdkFrameTimings
.- Returns:
true
if all information that will be available for the frame has been filled in.
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getFrameCounter
public long getFrameCounter()Gets the frame counter value of theGdkFrameClock
when this frame was drawn.- Returns:
- the frame counter value for this frame
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getFrameTime
public long getFrameTime()Returns the frame time for the frame.This is the time value that is typically used to time animations for the frame. See
FrameClock.getFrameTime()
.- Returns:
- the frame time for the frame, in the timescale of g_get_monotonic_time()
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getPredictedPresentationTime
public long getPredictedPresentationTime()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
getPresentationTime()
, which is only available after the frame has been presented.In general, if you are simply animating, you should use
FrameClock.getFrameTime()
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.- Returns:
- The predicted time at which the frame will be presented, in the timescale of g_get_monotonic_time(), or 0 if no predicted presentation time is available.
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getPresentationTime
public long getPresentationTime()Reurns the presentation time.This is the time at which the frame became visible to the user.
- Returns:
- the time the frame was displayed to the user, in the
timescale of g_get_monotonic_time(), or 0 if no presentation
time is available. See
getComplete()
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getRefreshInterval
public long getRefreshInterval()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”.
- Returns:
- the refresh interval of the display, in microseconds,
or 0 if the refresh interval is not available.
See
getComplete()
.
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ref
Increases the reference count of this FrameTimings.- Returns:
- this FrameTimings
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unref
public void unref()Decreases the reference count of this FrameTimings.If this FrameTimings is no longer referenced, it will be freed.
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