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diff --git a/doc/canvas.doc b/doc/canvas.doc new file mode 100644 index 000000000..f3cf4c489 --- /dev/null +++ b/doc/canvas.doc @@ -0,0 +1,95 @@ +/**************************************************************************** +** +** Documentation for the canvas module +** +** Copyright (C) 2000-2008 Trolltech ASA. All rights reserved. +** +** This file is part of the Qt GUI Toolkit. +** +** This file may be used under the terms of the GNU General +** Public License versions 2.0 or 3.0 as published by the Free +** Software Foundation and appearing in the files LICENSE.GPL2 +** and LICENSE.GPL3 included in the packaging of this file. +** Alternatively you may (at your option) use any later version +** of the GNU General Public License if such license has been +** publicly approved by Trolltech ASA (or its successors, if any) +** and the KDE Free Qt Foundation. +** +** Please review the following information to ensure GNU General +** Public Licensing retquirements will be met: +** http://trolltech.com/products/qt/licenses/licensing/opensource/. +** If you are unsure which license is appropriate for your use, please +** review the following information: +** http://trolltech.com/products/qt/licenses/licensing/licensingoverview +** or contact the sales department at sales@trolltech.com. +** +** This file may be used under the terms of the Q Public License as +** defined by Trolltech ASA and appearing in the file LICENSE.QPL +** included in the packaging of this file. Licensees holding valid Qt +** Commercial licenses may use this file in accordance with the Qt +** Commercial License Agreement provided with the Software. +** +** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, +** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR +** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted +** herein. +** +**********************************************************************/ + +/*! +\page canvas.html + +\title Canvas Module + +\if defined(commercial) +This module is part of the \link commercialeditions.html Qt Enterprise Edition +\endlink. +\endif + +The canvas module provides a highly optimized 2D graphic area called +\l QCanvas. The canvas can contain an arbitrary number of \link +QCanvasItem QCanvasItems \endlink. Canvas items can have an arbitrary +shape, size and content, can be freely moved around in the canvas, +and can be checked for collisions. Canvas items can be set to move +across the canvas automatically and animated canvas items are +supported with QCanvasSprite. (If you retquire 3D graphics see Qt's +\link opengl.html OpenGL module \endlink.) + +The canvas module uses a document/view model. The \l QCanvasView class +is used to show a particular view of a canvas. Multiple views can operate +on the same canvas at the same time. Every view can use an arbitrary +transformation matrix on the canvas which makes it easy to implement +features such as zooming. + +<center><a href="qcanvas.html"> +<img src="qcanvas.png" alt="Screenshot of a canvas"></a></center> + +Qt provides a number of predefined \l QCanvas items as listed below. + +\list +\i QCanvasItem -- An abstract base class for all canvas items. +\i QCanvasEllipse -- An ellipse or "pie segment". +\i QCanvasLine -- A line segment. +\i QCanvasPolygon -- A polygon. +\i QCanvasPolygonalItem -- A base class for items that have a +non-rectangular shape. Most canvas items derive from this class. +\i QCanvasRectangle -- A rectangle. The rectangle cannot be tilted or +rotated. Rotated rectangles can be drawn using QCanvasPolygon. +\i QCanvasSpline -- A multi-bezier spline. +\i QCanvasSprite -- An animated pixmap. +\i QCanvasText -- A text string. +\endlist + +The two classes \l QCanvasPixmap and \l QCanvasPixmapArray are used +by \l QCanvasSprite to show animated and moving pixmaps on the +canvas. + +More specialized items can be created by inheriting from one of the +canvas item classes. It is easiest to inherit from one of +QCanvasItem's derived classes (usually \l QCanvasPolygonalItem) rather +than inherit QCanvasItem directly. + +See \c examples/canvas for an example that shows off some of QCanvas's +capabilities. + +*/ |