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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 LinearGradient
\inqmlmodule QtGraphicalEffects 1.0
\since QtGraphicalEffects 1.0
\inherits QtQuick2::Item
\ingroup qtgraphicaleffects-gradient
\brief Draws a linear gradient.
A gradient is defined by two or more colors, which are blended seamlessly.
The colors start from the given start point and end to the given end point.
\table
\header
\li Effect applied
\row
\li \image LinearGradient.png
\endtable
\section1 Example
The following example shows how to apply the effect.
\snippet snippets/LinearGradient-example.qml example
*/
/*!
\qmlproperty Gradient QtGraphicalEffects1::LinearGradient::gradient
A gradient is defined by two or more colors, which are blended seamlessly.
The colors are specified as a set of GradientStop child items, each of which
defines a position on the gradient
from 0.0 to 1.0 and a color. The position of each GradientStop is defined by
the position property, and the color is definded by the color property.
\table
\header
\li Output examples with different gradient values
\li
\li
\row
\li \image LinearGradient_gradient1.png
\li \image LinearGradient_gradient2.png
\li \image LinearGradient_gradient3.png
\row
\li \b {gradient:} \code
Gradient {
GradientStop { position: 0.000
color: Qt.rgba(1, 0, 0, 1) }
GradientStop { position: 0.167;
color: Qt.rgba(1, 1, 0, 1) }
GradientStop { position: 0.333;
color: Qt.rgba(0, 1, 0, 1) }
GradientStop { position: 0.500;
color: Qt.rgba(0, 1, 1, 1) }
GradientStop { position: 0.667;
color: Qt.rgba(0, 0, 1, 1) }
GradientStop { position: 0.833;
color: Qt.rgba(1, 0, 1, 1) }
GradientStop { position: 1.000;
color: Qt.rgba(1, 0, 0, 1) }
}
\endcode
\li \b {gradient:} \code
Gradient {
GradientStop { position: 0.0
color: "#F0F0F0"
}
GradientStop { position: 0.5
color: "#000000"
}
GradientStop { position: 1.0
color: "#F0F0F0"
}
}
\endcode
\li \b {gradient:} \code
Gradient {
GradientStop { position: 0.0
color: "#00000000"
}
GradientStop { position: 1.0
color: "#FF000000"
}
}
\endcode
\row
\li \l start: Qt.point(0, 0)
\li \l start: Qt.point(0, 0)
\li \l start: Qt.point(0, 0)
\row
\li \l end: Qt.point(300, 300)
\li \l end: Qt.point(300, 300)
\li \l end: Qt.point(300, 300)
\endtable
*/
/*!
\qmlproperty variant QtGraphicalEffects1::LinearGradient::source
This property defines the item that is going to be filled with gradient. Source
item gets rendered into an intermediate pixel buffer and the alpha values
from the result are used to determine the gradient's pixels visibility in
the display.
The default value for source is undefined and in that case whole effect area
is filled with gradient.
\table
\header
\li Output examples with different source values
\li
\li
\row
\li \image LinearGradient_maskSource1.png
\li \image LinearGradient_maskSource2.png
\row
\li \b { source: undefined }
\li \b { source: Image { source: images/butterfly.png } }
\row
\li \l start: Qt.point(0, 0)
\li \l start: Qt.point(0, 0)
\row
\li \l end: Qt.point(300, 300)
\li \l end: Qt.point(300, 300)
\endtable
*/
/*!
\qmlproperty variant QtGraphicalEffects1::LinearGradient::start
This property defines the starting point where the color at gradient
position of 0.0 is rendered. Colors at larger position values are rendered
linearly towards the end point. The point is given in pixels and the default
value is Qt.point(0, 0).
Setting the default values for the start and \l{LinearGradient::end}{end} results in a full height
linear gradient on the y-axis.
\table
\header
\li Output examples with different start values
\li
\li
\row
\li \image LinearGradient_start1.png
\li \image LinearGradient_start2.png
\li \image LinearGradient_start3.png
\row
\li \b { start: QPoint(0, 0) }
\li \b { start: QPoint(150, 150) }
\li \b { start: QPoint(300, 0) }
\row
\li \l end: QPoint(300, 300)
\li \l end: QPoint(300, 300)
\li \l end: QPoint(300, 300)
\endtable
*/
/*!
\qmlproperty variant QtGraphicalEffects1::LinearGradient::end
This property defines the ending point where the color at gradient position
of 1.0 is rendered. Colors at smaller position values are rendered linearly
towards the start point. The point is given in pixels and the default value
is Qt.point(0, height).
Setting the default values for the \l{LinearGradient::start}{start} and end results in a full height
linear gradient on the y-axis.
\table
\header
\li Output examples with different end values
\li
\li
\row
\li \image LinearGradient_end1.png
\li \image LinearGradient_end2.png
\li \image LinearGradient_end3.png
\row
\li \b { end: Qt.point(300, 300) }
\li \b { end: Qt.point(150, 150) }
\li \b { end: Qt.point(300, 0) }
\row
\li \l start: Qt.point(0, 0)
\li \l start: Qt.point(0, 0)
\li \l start: Qt.point(0, 0)
\endtable
*/
/*!
\qmlproperty bool QtGraphicalEffects1::LinearGradient::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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