aboutsummaryrefslogtreecommitdiff
path: root/engines/engine.h
blob: 33416dda44bf80662b78088231b952c2a9045482 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
/* 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.
 */

#ifndef ENGINES_ENGINE_H
#define ENGINES_ENGINE_H

#include "common/scummsys.h"
#include "common/str.h"
#include "common/language.h"
#include "common/platform.h"

class OSystem;

namespace Audio {
class Mixer;
}
namespace Common {
class Error;
class EventManager;
class SaveFileManager;
class TimerManager;
class FSNode;
}
namespace GUI {
class Debugger;
class Dialog;
}

/**
 * Initializes graphics and shows error message.
 */
void GUIErrorMessage(const Common::String &msg);


class Engine {
public:
	OSystem *_system;
	Audio::Mixer *_mixer;

protected:
	Common::TimerManager *_timer;
	Common::EventManager *_eventMan;
	Common::SaveFileManager *_saveFileMan;

	GUI::Dialog *_mainMenuDialog;
	virtual int runDialog(GUI::Dialog &dialog);

	const Common::String _targetName; // target name for saves

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;

	/**
	 * The time when the pause was started.
	 */
	uint32 _pauseStartTime;

	/**
	 * The time when the engine was started. This value is used to calculate
	 * the current play time of the game running.
	 */
	int32 _engineStartTime;

	/**
	 * Save slot selected via global main menu.
	 * This slot will be loaded after main menu execution (not from inside
	 * the menu loop, to avoid bugs like #2822778).
	 */
	int _saveSlotToLoad;

public:


	/**
	 * A feature in this context means an ability of the engine which can be
	 * either available or not.
	 * @see Engine::hasFeature()
	 */
	enum EngineFeature {
		/**
		 * Enables the subtitle speed and toggle items in the Options section
		 * of the global main menu.
		 */
		kSupportsSubtitleOptions,

		/**
		 * 'Return to launcher' feature is supported, i.e., EVENT_RTL is handled
		 * either directly, or indirectly (that is, the engine calls and honors
		 * the result of the Engine::shouldQuit() method appropriately).
		 */
		kSupportsRTL,

		/**
		 * Loading savestates during runtime is supported, that is, this engine
		 * implements loadGameState() and canLoadGameStateCurrently().
		 * If this feature is supported, then the corresponding MetaEngine *must*
		 * support the kSupportsListSaves feature.
		 */
		kSupportsLoadingDuringRuntime,

		/**
		 * Loading savestates during runtime is supported, that is, this engine
		 * implements saveGameState() and canSaveGameStateCurrently().
		 * If this feature is supported, then the corresponding MetaEngine *must*
		 * support the kSupportsListSaves feature.
		 */
		kSupportsSavingDuringRuntime
	};



	/** @name Overloadable methods
	 *
	 *  All Engine subclasses should consider overloading some or all of the following methods.
	 */
	//@{

	Engine(OSystem *syst);
	virtual ~Engine();

	/**
	 * Init SearchMan according to the game path.
	 *
	 * By default it adds the directory in non-flat mode with a depth of 4 as
	 * priority 0 to SearchMan.
	 *
	 * @param gamePath The base directory of the game data.
	 */
	virtual void initializePath(const Common::FSNode &gamePath);

	/**
	 * Init the engine and start its main loop.
	 * @return returns kNoError on success, else an error code.
	 */
	virtual Common::Error run() = 0;

	/**
	 * Prepare an error string, which is printed by the error() function.
	 */
	virtual void errorString(const char *buf_input, char *buf_output, int buf_output_size);

	/**
	 * 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; }

	/**
	 * Determine whether the engine supports the specified feature.
	 */
	virtual bool hasFeature(EngineFeature f) const { return false; }

//	virtual EnginePlugin *getMetaEnginePlugin() const;

	/**
	 * 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.
	 * The default implementation sets the volume levels of all mixer sound
	 * types according to the config entries of the active domain.
	 * When overwriting, call the default implementation first, then adjust the
	 * volumes further (if required).
	 *
	 * @note When setting volume levels, respect the "mute" config entry.
	 * @note The volume for the plain sound type is reset to the maximum
	 *       volume. If the engine can associate its own value for this
	 *       type, it needs to overwrite this member and set it accordingly.
	 * @todo find a better name for this
	 */
	virtual void syncSoundSettings();

	/*
	 * Initialize any engine-specific keymaps.
	 */
	virtual void initKeymap() {}

	/*
	 * Cleanup any engine-specific keymaps.
	 */
	virtual void deinitKeymap();

	/**
	 * Flip mute all sound option.
	 */
	virtual void flipMute();

	/**
	 * Load a game state.
	 * @param slot	the slot from which a savestate should be loaded
	 * @return returns kNoError on success, else an error code.
	 */
	virtual Common::Error loadGameState(int slot);

	/**
	 * Sets the game slot for a savegame to be loaded after global
	 * main menu execution. This is to avoid loading a savegame from
	 * inside the menu loop which causes bugs like #2822778.
	 *
	 * @param slot	the slot from which a savestate should be loaded.
	 */
	void setGameToLoadSlot(int slot);

	/**
	 * Indicates whether a game state can be loaded.
	 */
	virtual bool canLoadGameStateCurrently();

	/**
	 * Save a game state.
	 * @param slot	the slot into which the savestate should be stored
	 * @param desc	a description for the savestate, entered by the user
	 * @return returns kNoError on success, else an error code.
	 */
	virtual Common::Error saveGameState(int slot, const Common::String &desc);

	/**
	 * Indicates whether a game state can be saved.
	 */
	virtual bool canSaveGameStateCurrently();

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.
	 */
	static void quitGame();

	/**
	 * Return whether the ENGINE should quit respectively should return to the
	 * launcher.
	 */
	static bool shouldQuit();

	/**
	 * 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();

	/**
	 * Display a warning to the user that the game is not fully supported.
	 *
	 * @return true if the user chose to start anyway, false otherwise
	 */
	static bool warnUserAboutUnsupportedGame();

	/**
	 * Get the total play time.
	 *
	 * @return How long the player has been playing in ms.
	 */
	uint32 getTotalPlayTime() const;

	/**
	 * Set the game time counter to the specified time.
	 *
	 * This can be used to set the play time counter after loading a savegame
	 * for example. Another use case is in case the engine wants to exclude
	 * time from the counter the user spent in original engine dialogs.
	 *
	 * @param time Play time to set up in ms.
	 */
	void setTotalPlayTime(uint32 time = 0);

	inline Common::TimerManager *getTimerManager() { return _timer; }
	inline Common::EventManager *getEventManager() { return _eventMan; }
	inline Common::SaveFileManager *getSaveFileManager() { return _saveFileMan; }

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);

};

// FIXME: HACK for MidiEmu & error()
extern Engine *g_engine;

#endif