[2] | 1 | /****************************************************************************
|
---|
| 2 | **
|
---|
[846] | 3 | ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
|
---|
[561] | 4 | ** All rights reserved.
|
---|
| 5 | ** Contact: Nokia Corporation ([email protected])
|
---|
[2] | 6 | **
|
---|
| 7 | ** This file is part of the documentation of the Qt Toolkit.
|
---|
| 8 | **
|
---|
[846] | 9 | ** $QT_BEGIN_LICENSE:FDL$
|
---|
[2] | 10 | ** Commercial Usage
|
---|
| 11 | ** Licensees holding valid Qt Commercial licenses may use this file in
|
---|
| 12 | ** accordance with the Qt Commercial License Agreement provided with the
|
---|
[846] | 13 | ** Software or, alternatively, in accordance with the terms contained in a
|
---|
| 14 | ** written agreement between you and Nokia.
|
---|
[2] | 15 | **
|
---|
[846] | 16 | ** GNU Free Documentation License
|
---|
| 17 | ** Alternatively, this file may be used under the terms of the GNU Free
|
---|
| 18 | ** Documentation License version 1.3 as published by the Free Software
|
---|
| 19 | ** Foundation and appearing in the file included in the packaging of this
|
---|
| 20 | ** file.
|
---|
[2] | 21 | **
|
---|
[561] | 22 | ** If you have questions regarding the use of this file, please contact
|
---|
| 23 | ** Nokia at [email protected].
|
---|
[2] | 24 | ** $QT_END_LICENSE$
|
---|
| 25 | **
|
---|
| 26 | ****************************************************************************/
|
---|
| 27 |
|
---|
| 28 | /*!
|
---|
| 29 | \example demos/deform
|
---|
| 30 | \title Vector Deformation
|
---|
| 31 |
|
---|
| 32 | This demo shows how to use advanced vector techniques to draw text
|
---|
| 33 | using a \c QPainterPath.
|
---|
| 34 |
|
---|
| 35 | \image deform-demo.png
|
---|
| 36 |
|
---|
| 37 | We define a vector deformation field in the shape of a lens and apply
|
---|
| 38 | this to all points in a path. This means that what is rendered on
|
---|
| 39 | screen is not pixel manipulation, but modified vector representations of
|
---|
| 40 | the glyphs themselves. This is visible from the high quality of the
|
---|
| 41 | antialiased edges for the deformed glyphs.
|
---|
| 42 |
|
---|
| 43 | To get a fairly complex path we allow the user to type in text and
|
---|
| 44 | convert the text to paths. This is done using the
|
---|
| 45 | QPainterPath::addText() function.
|
---|
| 46 |
|
---|
| 47 | The lens is drawn using a single call to QPainter::drawEllipse(),
|
---|
| 48 | using a QRadialGradient to fill it with a specialized color
|
---|
| 49 | table, giving the effect of the sun's reflection and a drop
|
---|
| 50 | shadow. The lens is cached as a pixmap for better performance.
|
---|
| 51 | */
|
---|