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/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the documentation of the Qt Graphical Effects module.
**
** $QT_BEGIN_LICENSE:FDL$
** GNU Free Documentation License
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms
** and conditions contained in a signed written agreement between you
** and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\qmltype FastBlur
\inqmlmodule QtGraphicalEffects 1.0
\since QtGraphicalEffects 1.0
\inherits QtQuick2::Item
\ingroup qtgraphicaleffects-blur
\brief Applies a fast blur effect to one or more source items.
FastBlur offers lower blur quality than
\l{QtGraphicalEffects1::GaussianBlur}{GaussianBlur}, but it is faster to
render. The FastBlur effect softens the source content by blurring it with
algorithm which uses the source content downscaling and bilinear filtering.
Use this effect in situations where the source content is rapidly changing
and the highest possible blur quality is not
needed.
\table
\header
\li Source
\li Effect applied
\row
\li \image Original_bug.png
\li \image FastBlur_bug.png
\endtable
\section1 Example
The following example shows how to apply the effect.
\snippet snippets/FastBlur-example.qml example
*/
/*!
\qmlproperty variant QtGraphicalEffects1::FastBlur::source
This property defines the source item that is going to be blurred.
*/
/*!
\qmlproperty real QtGraphicalEffects1::FastBlur::radius
This property defines the distance of the neighboring pixels which affect
the blurring of an individual pixel. A larger radius increases the blur
effect. FastBlur algorithm may internally reduce the accuracy of the radius in order to
provide good rendering performance.
The value ranges from 0.0 (no blur) to inf. Visual quality of the blur is reduced when
radius exceeds value 64. By default, the property is set to \c 0.0 (no blur).
\table
\header
\li Output examples with different blur values
\li
\li
\row
\li \image FastBlur_radius1.png
\li \image FastBlur_radius2.png
\li \image FastBlur_radius3.png
\row
\li \b { radius: 0 }
\li \b { radius: 32 }
\li \b { radius: 64 }
\endtable
*/
/*!
\qmlproperty bool QtGraphicalEffects1::FastBlur::transparentBorder
This property defines the blur behavior near the edges of the item, where
the pixel blurring is affected by the pixels outside the source edges.
If the property is set to \c true, the pixels outside the source are
interpreted to be transparent, which is similar to OpenGL clamp-to-border
extension. The blur is expanded slightly outside the effect item area.
If the property is set to \c false, the pixels outside the source are
interpreted to contain the same color as the pixels at the edge of the item,
which is similar to OpenGL clamp-to-edge behavior. The blur does not expand
outside the effect item area.
By default, the property is set to \c false.
\table
\header
\li Output examples with different transparentBorder values
\li
\li
\row
\li \image FastBlur_transparentBorder1.png
\li \image FastBlur_transparentBorder2.png
\row
\li \b { transparentBorder: false }
\li \b { transparentBorder: true }
\row
\li \l radius: 64
\li \l radius: 64
\endtable
*/
/*!
\qmlproperty bool QtGraphicalEffects1::FastBlur::cached
This property allows the effect output pixels to be cached in order to
improve the rendering performance.
Every time the source or effect properties are changed, the pixels in the
cache must be updated. Memory consumption is increased, because an extra
buffer of memory is required for storing the effect output.
It is recommended to disable the cache when the source or the effect
properties are animated.
By default, the property is set to \c false.
*/
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