doc/src/painting-and-printing/printing.qdoc
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+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
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+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+  \group printing
+  \title Printer and Printing APIs
+  \brief Classes for producing printed output
+  \ingroup groups
+*/
+
+/*!
+  \page printing.html
+  \title Printing with Qt
+
+  \previouspage Styling
+  \contentspage The Paint System
+
+  \brief A guide to producing printed output with Qt's paint system and widgets.
+
+  Qt provides extensive cross-platform support for printing. Using the printing
+  systems on each platform, Qt applications can print to attached printers and
+  across networks to remote printers. Qt's printing system also enables PostScript
+  and PDF files to be generated, providing the foundation for basic report
+  generation facilities.
+
+  \tableofcontents
+  
+  \section1 Classes Supporting Printing
+
+  The following classes support the selecting and setting up of printers and
+  printing output.
+  
+  \annotatedlist printing
+
+  \section1 Paint Devices and Printing
+
+  In Qt, printers are represented by QPrinter, a paint device that provides
+  functionality specific to printing, such as support for multiple pages and
+  double-sided output. As a result, printing involves using a QPainter to paint
+  onto a series of pages in the same way that you would paint onto a custom
+  widget or image.
+
+  \section2 Creating a QPrinter
+
+  Although QPrinter objects can be constructed and set up without requiring user
+  input, printing is often performed as a result of a request by the user;
+  for example, when the user selects the \gui{File|Print...} menu item in a GUI
+  application. In such cases, a newly-constructed QPrinter object is supplied to
+  a QPrintDialog, allowing the user to specify the printer to use, paper size, and
+  other printing properties.
+
+  \snippet examples/richtext/orderform/mainwindow.cpp 18
+
+  It is also possible to set certain default properties by modifying the QPrinter
+  before it is supplied to the print dialog. For example, applications that
+  generate batches of reports for printing may set up the QPrinter to
+  \l{QPrinter::setOutputFileName()}{write to a local file} by default rather than
+  to a printer.
+
+  \section2 Painting onto a Page
+
+  Once a QPrinter object has been constructed and set up, a QPainter can be used
+  to perform painting operations on it. We can construct and set up a painter in
+  the following way:
+
+  \snippet doc/src/snippets/printing-qprinter/object.cpp 0
+
+  Since the QPrinter starts with a blank page, we only need to call the
+  \l{QPrinter::}{newPage()} function after drawing each page, except for the
+  last page.
+
+  The document is sent to the printer, or written to a local file, when we call
+  \l{QPainter::}{end()}.
+
+  \section2 Coordinate Systems
+
+  QPrinter provides functions that can be used to obtain information about the
+  dimensions of the paper (the paper rectangle) and the dimensions of the
+  printable area (the page rectangle). These are given in logical device
+  coordinates that may differ from the physical coordinates used by the device
+  itself, indicating that the printer is able to render text and graphics at a
+  (typically higher) resolution than the user's display.
+
+  Although we do not need to handle the conversion between logical and physical
+  coordinates ourselves, we still need to apply transformations to painting
+  operations because the pixel measurements used to draw on screen are often
+  too small for the higher resolutions of typical printers.
+
+  \table
+  \row \o \bold{Printer and Painter Coordinate Systems}
+
+  The \l{QPrinter::}{paperRect()} and \l{QPrinter::}{pageRect()} functions
+  provide information about the size of the paper used for printing and the
+  area on it that can be painted on.
+
+  The rectangle returned by \l{QPrinter::}{pageRect()} usually lies inside
+  the rectangle returned by \l{QPrinter::}{paperRect()}. You do not need to
+  take the positions and sizes of these area into account when using a QPainter
+  with a QPrinter as the underlying paint device; the origin of the painter's
+  coordinate system will coincide with the top-left corner of the page
+  rectangle, and painting operations will be clipped to the bounds of the
+  drawable part of the page.
+
+  \o \inlineimage printer-rects.png
+  \endtable
+
+  The paint system automatically uses the correct device metrics when painting
+  text but, if you need to position text using information obtained from
+  font metrics, you need to ensure that the print device is specified when
+  you construct QFontMetrics and QFontMetricsF objects, or ensure that each QFont
+  used is constructed using the form of the constructor that accepts a
+  QPaintDevice argument.
+
+  \section1 Printing from Complex Widgets
+
+  Certain widgets, such as QTextEdit and QGraphicsView, display rich content
+  that is typically managed by instances of other classes, such as QTextDocument
+  and QGraphicsScene. As a result, it is these content handling classes that
+  usually provide printing functionality, either via a function that can be used
+  to perform the complete task, or via a function that accepts an existing
+  QPainter object. Some widgets provide convenience functions to expose underlying
+  printing features, avoiding the need to obtain the content handler just to call
+  a single function.
+
+  The following table shows which class and function are responsible for
+  printing from a selection of different widgets. For widgets that do not expose
+  printing functionality directly, the content handling classes containing this
+  functionality can be obtained via a function in the corresponding widget's API.
+
+  \table
+  \header \o Widget         \o Printing function        \o Accepts
+  \row    \o QGraphicsView  \o QGraphicsView::render()  \o QPainter
+  \row    \o QSvgWidget     \o QSvgRenderer::render()   \o QPainter
+  \row    \o QTextEdit      \o QTextDocument::print()   \o QPrinter
+  \row    \o QTextLayout    \o QTextLayout::draw()      \o QPainter
+  \row    \o QTextLine      \o QTextLine::draw()        \o QPainter
+  \endtable
+
+  QTextEdit requires a QPrinter rather than a QPainter because it uses information
+  about the configured page dimensions in order to insert page breaks at the most
+  appropriate places in printed documents.
+*/
+
+/*!
+  \page pdf-licensing.html
+  \title Notes about PDF Licensing
+  \ingroup licensing
+  \brief Details of restrictions on the use of PDF-related trademarks.
+
+  Please note that Adobe\reg places restrictions on the use of its trademarks
+  (including logos) in conjunction with PDF; e.g. "Adobe PDF". Please refer
+  to \l{http://www.adobe.com}{www.adobe.com} for guidelines.
+*/