// Copyright (C) 2020 The Qt Company Ltd. // Copyright (C) 2017 Jolla Ltd, author: // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only // Qt-Security score:significant reason:default import QtQuick import Qt5Compat.GraphicalEffects.private /*! \qmltype Glow \inqmlmodule Qt5Compat.GraphicalEffects \since QtGraphicalEffects 1.0 \inherits QtQuick::Item \ingroup qtgraphicaleffects-glow \brief Generates a blurred and colorized image of the source and places it behind the original, giving impression that the source is glowing. \table \header \li Source \li Effect applied \row \li \image Original_butterfly_black.png {White butterfly on black background} \li \image Glow_butterfly.png {Butterfly with glowing edges} \endtable \section1 Example The following example shows how to apply the effect. \snippet Glow-example.qml example */ Item { id: root DropShadowBase { id: dps anchors.fill: parent color: "white" spread: 0.5 horizontalOffset: 0 verticalOffset: 0 } /*! This property defines the source item that is going to be used as source for the generated glow. \note It is not supported to let the effect include itself, for instance by setting source to the effect's parent. */ property alias source: dps.source /*! Radius defines the softness of the glow. A larger radius causes the edges of the glow to appear more blurry. Depending on the radius value, value of the \l{Glow::samples}{samples} should be set to sufficiently large to ensure the visual quality. The ideal blur is achieved by selecting \c samples and \c radius such that \c {samples = 1 + radius * 2}, such as: \table \header \li Radius \li Samples \row \li 0 \e{(no blur)} \li 1 \row \li 1 \li 3 \row \li 2 \li 5 \row \li 3 \li 7 \endtable By default, the property is set to \c {floor(samples/2)}. \table \header \li Output examples with different radius values \li \li \row \li \image Glow_radius1.png {No glow effect} \li \image Glow_radius2.png {Moderate glow radius} \li \image Glow_radius3.png {Large glow radius} \row \li \b { radius: 0 } \li \b { radius: 6 } \li \b { radius: 12 } \row \li \l samples: 25 \li \l samples: 25 \li \l samples: 25 \row \li \l color: #ffffff \li \l color: #ffffff \li \l color: #ffffff \row \li \l spread: 0 \li \l spread: 0 \li \l spread: 0 \endtable */ property alias radius: dps.radius /*! This property defines how many samples are taken per pixel when edge softening blur calculation is done. Larger value produces better quality, but is slower to render. Ideally, this value should be twice as large as the highest required radius value plus one, such as: \table \header \li Radius \li Samples \row \li 0 \e{(no blur)} \li 1 \row \li 1 \li 3 \row \li 2 \li 5 \row \li 3 \li 7 \endtable By default, the property is set to \c 9. This property is not intended to be animated. Changing this property will cause the underlying OpenGL shaders to be recompiled. */ property alias samples: dps.samples /*! This property defines how large part of the glow color is strengthened near the source edges. The values range from 0.0 to 1.0. By default, the property is set to \c 0.5. \note The implementation is optimized for medium and low spread values. Depending on the source, spread values closer to 1.0 may yield visually asymmetrical results. \table \header \li Output examples with different spread values \li \li \row \li \image Glow_spread1.png {Glow with no spread} \li \image Glow_spread2.png {Glow with medium spread} \li \image Glow_spread3.png {Glow with full spread} \row \li \b { spread: 0.0 } \li \b { spread: 0.5 } \li \b { spread: 1.0 } \row \li \l radius: 8 \li \l radius: 8 \li \l radius: 8 \row \li \l samples: 17 \li \l samples: 17 \li \l samples: 17 \row \li \l color: #ffffff \li \l color: #ffffff \li \l color: #ffffff \endtable */ property alias spread: dps.spread /*! This property defines the RGBA color value which is used for the glow. By default, the property is set to \c "white". \table \header \li Output examples with different color values \li \li \row \li \image Glow_color1.png {White glow effect} \li \image Glow_color2.png {Green glow effect} \li \image Glow_color3.png {Semi-transparent green glow} \row \li \b { color: #ffffff } \li \b { color: #00ff00 } \li \b { color: #aa00ff00 } \row \li \l radius: 8 \li \l radius: 8 \li \l radius: 8 \row \li \l samples: 17 \li \l samples: 17 \li \l samples: 17 \row \li \l spread: 0.5 \li \l spread: 0.5 \li \l spread: 0.5 \endtable */ property alias color: dps.color /*! \internal Starting Qt 5.6, this property has no effect. It is left here for source compatibility only. ### Qt 6: remove */ property bool fast: false /*! 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. */ property alias cached: dps.cached /*! This property determines whether or not the effect has a transparent border. When set to \c true, the exterior of the item is padded with a transparent edge, making sampling outside the source texture use transparency instead of the edge pixels. Without this property, an image which has opaque edges will not get a blurred edge. By default, the property is set to \c true. Set it to false if the source already has a transparent edge to make the blurring a tiny bit faster. In the snippet below, the Rectangle on the left has transparent borders and has blurred edges, whereas the Rectangle on the right does not. \snippet Glow-transparentBorder-example.qml example \image Glow-transparentBorder.png {Rectangles showing difference between transparent border settings} */ property alias transparentBorder: dps.transparentBorder }