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// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\page qtquick-production-quality-animation.html
\previouspage qtquick-editing-easing-curves.html
\nextpage qtquick-optimizing-designs.html
\title Production Quality
After the wireframing and prototyping phases, you can use previewing and
profiling tools to fine-tune your UI for production.
How to achieve production quality motion in UIs:
\list
\li Preview the UI to check the FPS refresh rate.
\li Profile the UI code to find causes for slowness, unresponsiveness,
and stuttering.
\endlist
\section1 FPS Refresh Rate
As a general rule, animators strive to allow the rendering engine to
achieve a consistent 60 frames-per-second (FPS) refresh rate. 60 FPS
means that there is approximately 16 milliseconds between each frame
in which processing can be done, which includes the processing required
to upload the draw primitives to the graphics hardware.
The frames-per-second (FPS) refresh rate of animations is displayed in the
\uicontrol FPS field on the \l{Summary of Main Toolbar Actions}{toolbar}
in the \uicontrol Design mode.
To improve the FPS rate, application developers should:
\list
\li Use asynchronous, event-driven programming wherever possible.
\li Use worker threads to do significant processing.
\li Never manually spin the event loop.
\li Never spend more than a couple of milliseconds per frame within
blocking functions to avoid skipped frames, which negatively
affect the user experience.
\endlist
For more information about previewing UIs on devices, see
\l{Validating with Target Hardware}.
\section1 Profiling UI Code
You can use \l{Profiling QML Applications}{QML Profiler} that is integrated
into \QC to find causes for typical performance problems in your UI. For
example, your UI might be slow, unresponsive, or stuttering. Typically, such
problems are caused by executing too much JavaScript in too few frames. All
JavaScript must return before the GUI thread can proceed, and frames are
delayed or dropped if the GUI thread is not ready.
In general, knowing where time is spent in a UI enables you to focus on
problem areas that actually exist, rather than problem areas that
potentially exist.
Determining which bindings are being run the most often or which functions
your application is spending the most time on enables you to decide whether
you need to optimize the problem areas, or redesign some implementation
details of your application so that the performance is improved. Attempting
to optimize code without profiling is likely to result in very minor rather
than significant performance improvements.
For more information, see \l{Profiling QML Applications}.
*/
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