engine.h
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*/
#ifndef ENGINES_ENGINE_H
#define ENGINES_ENGINE_H
#include "common/scummsys.h"
#include "common/events.h"
#include "common/fs.h"
#include "common/str.h"
#include "engines/metaengine.h"
class OSystem;
namespace Audio {
class Mixer;
}
namespace Common {
class EventManager;
class SaveFileManager;
class TimerManager;
}
namespace GUI {
class Debugger;
class Dialog;
}
/**
* Setup the backend's graphics mode.
*/
void initCommonGFX(bool defaultTo1XScaler);
/**
* Initialized graphics and shows error message.
*/
void GUIErrorMessage(const Common::String msg);
class Engine {
public:
OSystem *_system;
Audio::Mixer *_mixer;
Common::TimerManager * _timer;
protected:
Common::EventManager *_eventMan;
Common::SaveFileManager *_saveFileMan;
GUI::Dialog *_mainMenuDialog;
virtual int runDialog(GUI::Dialog &dialog);
const Common::String _targetName; // target name for saves
const Common::FSNode _gameDataDir;
private:
/**
* The pause level, 0 means 'running', a positive value indicates
* how often the engine has been paused (and hence how often it has
* to be un-paused before it resumes running). This makes it possible
* to nest code which pauses the engine.
*/
int _pauseLevel;
public:
/** @name Overloadable methods
*
* All Engine subclasses should consider overloading some or all of the following methods.
*/
//@{
Engine(OSystem *syst);
virtual ~Engine();
/**
* Init the engine.
* @return 0 for success, else an error code.
*/
virtual int init() = 0;
/**
* Start the main engine loop.
* The return value is not yet used, but could indicate whether the user
* wants to return to the launch or to fully quit ScummVM.
* @return 0 for success, else an error code.
*/
virtual int go() = 0;
/**
* Prepare an error string, which is printed by the error() function.
*/
virtual void errorString(const char *buf_input, char *buf_output);
/**
* Return the engine's debugger instance, if any. Used by error() to
* invoke the debugger when a severe error is reported.
*/
virtual GUI::Debugger *getDebugger() { return 0; }
/**
* Notify the engine that the sound settings in the config manager may have
* changed and that it hence should adjust any internal volume etc. values
* accordingly.
* @todo find a better name for this
*/
virtual void syncSoundSettings();
protected:
/**
* Actual implementation of pauseEngine by subclasses. See there
* for details.
*/
virtual void pauseEngineIntern(bool pause);
//@}
public:
/**
* Request the engine to quit. Sends a EVENT_QUIT event to the Event
* Manager.
*/
void quitGame();
/**
* Return whether the ENGINE should quit respectively should return to the
* launcher.
*/
bool shouldQuit() const { return (_eventMan->shouldQuit() || _eventMan->shouldRTL()); }
/**
* Pause or resume the engine. This should stop/resume any audio playback
* and other stuff. Called right before the system runs a global dialog
* (like a global pause, main menu, options or 'confirm exit' dialog).
*
* This is a convenience tracker which automatically keeps track on how
* often the engine has been paused, ensuring that after pausing an engine
* e.g. twice, it has to be unpaused twice before actuallying resuming.
*
* @param pause true to pause the engine, false to resume it
*/
void pauseEngine(bool pause);
/**
* Return whether the engine is currently paused or not.
*/
bool isPaused() const { return _pauseLevel != 0; }
/**
* Run the Global Main Menu Dialog
*/
void openMainMenuDialog();
/**
* Determine whether the engine supports the specified MetaEngine feature.
*
* FIXME: This should not call through to the MetaEngine, but rather should support
* its own list of features. In particular, kSupportsRTL should be an EngineFeature,
* not a MetaEngineFeature.
*/
bool hasFeature(MetaEngine::MetaEngineFeature f);
public:
/** On some systems, check if the game appears to be run from CD. */
void checkCD();
protected:
/**
* Indicate whether an autosave should be performed.
*/
bool shouldPerformAutoSave(int lastSaveTime);
};
extern Engine *g_engine;
#endif