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diff --git a/doc/src/examples/tankgame.qdoc b/doc/src/examples/tankgame.qdoc deleted file mode 100644 index 536e5821d..000000000 --- a/doc/src/examples/tankgame.qdoc +++ /dev/null @@ -1,117 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). -** 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 either Technology Preview License Agreement or the -** Beta Release License Agreement. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** 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 1.0, included in the file LGPL_EXCEPTION.txt in this -** package. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 3.0 as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL included in the -** packaging of this file. Please review the following information to -** ensure the GNU General Public License version 3.0 requirements will be -** met: http://www.gnu.org/copyleft/gpl.html. -** -** If you are unsure which license is appropriate for your use, please -** contact the sales department at http://www.qtsoftware.com/contact. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example statemachine/tankgame - \title Tank Game Example - - The Tank Game example is part of the in \l{The State Machine Framework}. It shows how to use - parallel states to implement artificial intelligence controllers that run in parallel, and error - states to handle run-time errors in parts of the state graph created by external plugins. - - \image tankgame-example.png - - In this example we write a simple game. The application runs a state machine with two main - states: A "stopped" state and a "running" state. The user can load plugins from the disk by - selecting the "Add tank" menu item. - - When the "Add tank" menu item is selected, the "plugins" subdirectory in the example's - directory is searched for compatible plugins. If any are found, they will be listed in a - dialog box created using QInputDialog::getItem(). - - \snippet examples/statemachine/tankgame/mainwindow.cpp 1 - - If the user selects a plugin, the application will construct a TankItem object, which inherits - from QGraphicsItem and QObject, and which implements an agreed-upon interface using the - meta-object mechanism. - - \snippet examples/statemachine/tankgame/tankitem.h 0 - - The tank item will be passed to the plugin's create() function. This will in turn return a - QState object which is expected to implement an artificial intelligence which controls the - tank and attempts to destroy other tanks it detects. - - \snippet examples/statemachine/tankgame/mainwindow.cpp 2 - - Each returned QState object becomes a descendant of a \c region in the "running" state, which is - defined as a parallel state. This means that entering the "running" state will cause each of the - plugged-in QState objects to be entered simultaneously, allowing the tanks to run independently - of each other. - - \snippet examples/statemachine/tankgame/mainwindow.cpp 0 - - The maximum number of tanks on the map is four, and when this number is reached, the - "Add tank" menu item should be disabled. This is implemented by giving the "stopped" state two - children which define whether the map is full or not. - - \snippet examples/statemachine/tankgame/mainwindow.cpp 5 - - To make sure that we go into the correct child state when returning from the "running" state - (if the "Stop game" menu item is selected while the game is running) we also give the "stopped" - state a history state which we make the initial state of "stopped" state. - - \snippet examples/statemachine/tankgame/mainwindow.cpp 3 - - Since part of the state graph is defined by external plugins, we have no way of controlling - whether they contain errors. By default, run-time errors are handled in the state machine by - entering a top level state which prints out an error message and never exits. If we were to - use this default behavior, a run-time error in any of the plugins would cause the "running" - state to exit, and thus all the other tanks to stop running as well. A better solution would - be if the broken plugin was disabled and the rest of the tanks allowed to continue as before. - - This is done by setting the error state of the plugin's top-most state to a special error state - defined specifically for the plugin in question. - - \snippet examples/statemachine/tankgame/mainwindow.cpp 4 - - If a run-time error occurs in \c pluginState or any of its descendants, the state machine will - search the hierarchy of ancestors until it finds a state whose error state is different from - \c null. (Note that if we are worried that a plugin could inadvertedly be overriding our - error state, we could search the descendants of \c pluginState and verify that their error - states are set to \c null before accepting the plugin.) - - The specialized \c errorState sets the "enabled" property of the tank item in question to false, - causing it to be painted with a red cross over it to indicate that it is no longer running. - Since the error state is a child of the same region in the parallel "running" state as - \c pluginState, it will not exit the "running" state, and the other tanks will continue running - without disruption. - -*/ |