54 lines
2.3 KiB
Plaintext
54 lines
2.3 KiB
Plaintext
/****************************************************************************
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**
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** Copyright (C) 2016 The Qt Company Ltd.
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** Contact: https://www.qt.io/licensing/
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**
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** This file is part of the documentation of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:FDL$
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** Commercial License Usage
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** Licensees holding valid commercial Qt licenses may use this file in
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** accordance with the commercial license agreement provided with the
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** Software or, alternatively, in accordance with the terms contained in
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** a written agreement between you and The Qt Company. For licensing terms
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** and conditions see https://www.qt.io/terms-conditions. For further
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** information use the contact form at https://www.qt.io/contact-us.
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**
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** GNU Free Documentation License Usage
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** Alternatively, this file may be used under the terms of the GNU Free
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** Documentation License version 1.3 as published by the Free Software
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** Foundation and appearing in the file included in the packaging of
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** this file. Please review the following information to ensure
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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/*!
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\example painting/deform
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\title Vector Deformation
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\ingroup examples-painting
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\brief Demonstrates how to manipulate the elements of a QPainterPath.
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\brief This example shows how to use advanced vector techniques to draw text
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using a \c QPainterPath.
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\image deform-demo.png
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We define a vector deformation field in the shape of a lens and apply
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this to all points in a path. This means that what is rendered on
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screen is not pixel manipulation, but modified vector representations of
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the glyphs themselves. This is visible from the high quality of the
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antialiased edges for the deformed glyphs.
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To get a fairly complex path we allow the user to type in text and
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convert the text to paths. This is done using the
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QPainterPath::addText() function.
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The lens is drawn using a single call to QPainter::drawEllipse(),
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using a QRadialGradient to fill it with a specialized color
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table, giving the effect of the sun's reflection and a drop
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shadow. The lens is cached as a pixmap for better performance.
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*/
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