| Copyright | Will Thompson Iñaki García Etxebarria and Jonas Platte |
|---|---|
| License | LGPL-2.1 |
| Maintainer | Iñaki García Etxebarria (garetxe@gmail.com) |
| Safe Haskell | None |
| Language | Haskell2010 |
GI.Gdk.Structs.FrameTimings
Contents
Description
A FrameTimings object holds timing information for a single frame
of the application’s displays. To retrieve FrameTimings objects,
use frameClockGetTimings or frameClockGetCurrentTimings.
The information in FrameTimings 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.
Synopsis
- newtype FrameTimings = FrameTimings (ManagedPtr FrameTimings)
- noFrameTimings :: Maybe FrameTimings
- frameTimingsGetComplete :: (HasCallStack, MonadIO m) => FrameTimings -> m Bool
- frameTimingsGetFrameCounter :: (HasCallStack, MonadIO m) => FrameTimings -> m Int64
- frameTimingsGetFrameTime :: (HasCallStack, MonadIO m) => FrameTimings -> m Int64
- frameTimingsGetPredictedPresentationTime :: (HasCallStack, MonadIO m) => FrameTimings -> m Int64
- frameTimingsGetPresentationTime :: (HasCallStack, MonadIO m) => FrameTimings -> m Int64
- frameTimingsGetRefreshInterval :: (HasCallStack, MonadIO m) => FrameTimings -> m Int64
- frameTimingsRef :: (HasCallStack, MonadIO m) => FrameTimings -> m FrameTimings
- frameTimingsUnref :: (HasCallStack, MonadIO m) => FrameTimings -> m ()
Exported types
newtype FrameTimings Source #
Memory-managed wrapper type.
Constructors
| FrameTimings (ManagedPtr FrameTimings) |
Instances
| BoxedObject FrameTimings Source # | |
Defined in GI.Gdk.Structs.FrameTimings Methods boxedType :: FrameTimings -> IO GType # | |
noFrameTimings :: Maybe FrameTimings Source #
A convenience alias for Nothing :: Maybe FrameTimings.
Methods
getComplete
frameTimingsGetComplete Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m Bool | Returns: |
The timing information in a FrameTimings 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 FrameTimings 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 frameTimingsGetComplete returns
True for a frame, you can be certain that no further values
will become available and be stored in the FrameTimings.
Since: 3.8
getFrameCounter
frameTimingsGetFrameCounter Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m Int64 | Returns: the frame counter value for this frame |
Gets the frame counter value of the FrameClock when this
this frame was drawn.
Since: 3.8
getFrameTime
frameTimingsGetFrameTime Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m Int64 | Returns: the frame time for the frame, in the timescale
of |
Returns the frame time for the frame. This is the time value
that is typically used to time animations for the frame. See
frameClockGetFrameTime.
getPredictedPresentationTime
frameTimingsGetPredictedPresentationTime Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m Int64 | Returns: The predicted time at which the frame will be presented,
in the timescale of |
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
frameTimingsGetPresentationTime, which is only available
after the frame has been presented. In general, if you are simply
animating, you should use frameClockGetFrameTime 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.
Since: 3.8
getPresentationTime
frameTimingsGetPresentationTime Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m Int64 | Returns: the time the frame was displayed to the user, in the
timescale of |
Reurns the presentation time. This is the time at which the frame became visible to the user.
Since: 3.8
getRefreshInterval
frameTimingsGetRefreshInterval Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m Int64 | Returns: the refresh interval of the display, in microseconds,
or 0 if the refresh interval is not available.
See |
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”.
Since: 3.8
ref
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m FrameTimings | Returns: |
Increases the reference count of timings.
Since: 3.8
unref
Arguments
| :: (HasCallStack, MonadIO m) | |
| => FrameTimings |
|
| -> m () |
Decreases the reference count of timings. If timings
is no longer referenced, it will be freed.
Since: 3.8