| 1 | /****************************************************************************
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| 2 | **
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| 3 | ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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| 4 | ** Contact: Qt Software Information (qt-info@nokia.com)
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| 5 | **
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| 6 | ** This file is part of the documentation of the Qt Toolkit.
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| 7 | **
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| 8 | ** $QT_BEGIN_LICENSE:LGPL$
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| 9 | ** Commercial Usage
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| 13 | ** a written agreement between you and Nokia.
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| 14 | **
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| 15 | ** GNU Lesser General Public License Usage
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| 16 | ** Alternatively, this file may be used under the terms of the GNU Lesser
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| 17 | ** General Public License version 2.1 as published by the Free Software
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| 28 | ** GNU General Public License Usage
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| 29 | ** Alternatively, this file may be used under the terms of the GNU
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| 30 | ** General Public License version 3.0 as published by the Free Software
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| 38 | ** $QT_END_LICENSE$
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| 39 | **
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| 40 | ****************************************************************************/
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| 41 |
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| 42 | /*!
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| 43 | \example demos/deform
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| 44 | \title Vector Deformation
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| 45 |
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| 46 | This demo shows how to use advanced vector techniques to draw text
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| 47 | using a \c QPainterPath.
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| 48 |
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| 49 | \image deform-demo.png
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| 50 |
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| 51 | We define a vector deformation field in the shape of a lens and apply
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| 52 | this to all points in a path. This means that what is rendered on
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| 53 | screen is not pixel manipulation, but modified vector representations of
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| 54 | the glyphs themselves. This is visible from the high quality of the
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| 55 | antialiased edges for the deformed glyphs.
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| 56 |
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| 57 | To get a fairly complex path we allow the user to type in text and
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| 58 | convert the text to paths. This is done using the
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| 59 | QPainterPath::addText() function.
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| 60 |
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| 61 | The lens is drawn using a single call to QPainter::drawEllipse(),
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| 62 | using a QRadialGradient to fill it with a specialized color
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| 63 | table, giving the effect of the sun's reflection and a drop
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| 64 | shadow. The lens is cached as a pixmap for better performance.
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| 65 | */
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