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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** 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.
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \qmlclass FastBlur
+ \inqmlmodule QtGraphicalEffects
+ \brief Applies a fast blur effect to one or more source items.
+
+ FastBlur offers lower blur quality than \l
+ {QtGraphicalEffects::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
+ \o Source
+ \o Effect applied
+ \row
+ \o \image Original_bug.png
+ \o \image FastBlur_bug.png
+ \endtable
+
+ \section1 Example
+
+ The following example shows how to apply the effect.
+ \snippet snippets/FastBlur-example.qml example
+
+ \section1 Memory Consumption
+
+ The internal memory consumption is approximately twice the memory
+ consumption of the the source item area in pixels.
+ If source item is not Image or ShaderEffectSource, then effect internally creates one ShaderEffectSource item per source.
+ Enabling the effect cache increases the memory consumption because an extra
+ buffer is allocated for the effect output.
+
+ \table
+ \header
+ \o Estimated memory usage for an effect with a size of 640x480 pixels with 32 bits per pixel (bpp)
+ \o
+ \row
+ \o Effect internal
+ \o 2.4 MB
+ \row
+ \o ShaderEffectSource (if used)
+ \o 1.2 MB
+ \row
+ \o Effect internal cache (if enabled)
+ \o 1.2 MB
+ \row
+ \o TOTAL (max)
+ \o 4.8 MB
+ \endtable
+
+*/
+
+/*!
+ \qmlproperty variant QtGraphicalEffects::FastBlur::source
+
+ This property defines the source item that is going to be blurred.
+
+*/
+/*!
+ \qmlproperty real QtGraphicalEffects::FastBlur::blur
+
+ BlurLevel defines the level of blurring, value 0.0 represents the source as
+ unblurred and value 1.0 blurs the source maximally.
+
+ The value ranges from 0.0 (no blur) to 1.0 (maximum blur). By default, the
+ property is set to \c 0.0 (no blur).
+
+ \table
+ \header
+ \o Output examples with different blur values
+ \o
+ \o
+ \row
+ \o \image FastBlur_blur1.png
+ \o \image FastBlur_blur2.png
+ \o \image FastBlur_blur3.png
+ \row
+ \o \bold { blur: 0.0 }
+ \o \bold { blur: 0.5 }
+ \o \bold { blur: 1.0 }
+ \endtable
+*/
+
+/*!
+ \qmlproperty bool QtGraphicalEffects::FastBlur::transparentBorder
+
+ This property defines the blur near the edges of the item, where the pixel
+ blurring is affected by the pixels just outside the source.
+
+ Setting this property to \c false, interprets the pixels outside the item
+ according to the OpenGL clamp-to-edge mode. If the source is Image, the pixels
+ are interpreted according to the Image::fillMode property. If the source is
+ ShaderEffectSource, the pixels are interpreted according to the
+ ShaderEffectSource::wrapMode property.
+
+ Setting this property to \c true, interprets the pixels outside the item to
+ be transparent. This behavior is similar to the OpenGL clamp-to-border
+ extension. The blur is expanded slightly outside the effect item area.
+
+ By default, the property is set to \c false.
+
+ \table
+ \header
+ \o Output examples with different transparentBorder values
+ \o
+ \o
+ \row
+ \o \image FastBlur_transparentBorder1.png
+ \o \image FastBlur_transparentBorder2.png
+ \row
+ \o \bold { transparentBorder: false }
+ \o \bold { transparentBorder: true }
+ \row
+ \o \l blur: 1
+ \o \l blur: 1
+ \endtable
+
+*/
+
+/*!
+ \qmlproperty bool QtGraphicalEffects::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.
+
+*/