Merge pull request #636 from sev-/lab

This is a pull request for the game The Labyrinth of Time. This game is
currently available on www.wyrmkeep.com and on GOG.com. The game should
be completable: it was completable a month ago and we did regularly
regression testing. All the work has been based on sources kindly
provided by Wyrmkeep.

The DOS and the Windows versions are supported by this engine.

This is a manual merge of the PR, with some history fixups.

1 files changed, 1190 insertions, 0 deletions

diff --git a/engines/lab/engine.cpp b/engines/lab/engine.cpp
new file mode 100644
index 0000000000..cbac66e855
--- /dev/null
+++ b/engines/lab/engine.cpp
@@ -0,0 +1,1190 @@
+/* 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.
+ *
+ */
+
+/*
+ * This code is based on Labyrinth of Time code with assistance of
+ *
+ * Copyright (c) 1993 Terra Nova Development
+ * Copyright (c) 2004 The Wyrmkeep Entertainment Co.
+ *
+ */
+
+#include "lab/lab.h"
+
+#include "lab/anim.h"
+#include "lab/dispman.h"
+#include "lab/eventman.h"
+#include "lab/image.h"
+#include "lab/intro.h"
+#include "lab/labsets.h"
+#include "lab/music.h"
+#include "lab/processroom.h"
+#include "lab/resource.h"
+#include "lab/tilepuzzle.h"
+#include "lab/utils.h"
+
+namespace Lab {
+
+// LAB: Labyrinth specific code for the special puzzles
+#define SPECIALLOCK         100
+#define SPECIALBRICK        101
+#define SPECIALBRICKNOMOUSE 102
+
+enum Items {
+	kItemHelmet = 1,
+	kItemBelt = 3,
+	kItemPithHelmet = 7,
+	kItemJournal = 9,
+	kItemNotes = 12,
+	kItemWestPaper = 18,
+	kItemWhiskey = 25,
+	kItemLamp = 27,
+	kItemMap = 28,
+	kItemQuarter = 30
+};
+
+#define kCondLampOn         151
+#define kCondBeltGlowing     70
+#define kCondUsedHelmet     184
+
+enum Monitors {
+	kMonitorMuseum = 71,
+	kMonitorGramophone = 72,
+	kMonitorUnicycle = 73,
+	kMonitorStatue = 74,
+	kMonitorTalisman = 75,
+	kMonitorLute = 76,
+	kMonitorClock = 77,
+	kMonitorWindow = 78,
+	//kMonitorBelt = 79,
+	kMonitorLibrary = 80,
+	kMonitorTerminal = 81
+	//kMonitorLevers = 82
+};
+
+enum MainButtons {
+	kButtonPickup,
+	kButtonUse,
+	kButtonOpen,
+	kButtonClose,
+	kButtonLook,
+	kButtonInventory,
+	kButtonLeft,
+	kButtonForward,
+	kButtonRight,
+	kButtonMap
+};
+
+enum AltButtons {
+	kButtonMainDisplay,
+	kButtonSaveLoad,
+	kButtonUseItem,
+	kButtonLookAtItem,
+	kButtonPrevItem,
+	kButtonNextItem,
+	kButtonBreadCrumbs,
+	kButtonFollowCrumbs
+};
+
+static char initColors[] = { '\x00', '\x00', '\x00', '\x30',
+							 '\x30', '\x30', '\x10', '\x10',
+							 '\x10', '\x14', '\x14', '\x14',
+							 '\x20', '\x20', '\x20', '\x24',
+							 '\x24', '\x24', '\x2c', '\x2c',
+							 '\x2c', '\x08', '\x08', '\x08' };
+
+uint16 LabEngine::getQuarters() {
+	return _inventory[kItemQuarter]._quantity;
+}
+
+void LabEngine::setQuarters(uint16 quarters) {
+	_inventory[kItemQuarter]._quantity = quarters;
+}
+
+void LabEngine::drawRoomMessage(uint16 curInv, CloseDataPtr closePtr) {
+	if (_lastTooLong) {
+		_lastTooLong = false;
+		return;
+	}
+
+	if (_alternate) {
+		if ((curInv <= _numInv) && _conditions->in(curInv) && !_inventory[curInv]._bitmapName.empty()) {
+			if ((curInv == kItemLamp) && _conditions->in(kCondLampOn))
+				// LAB: Labyrinth specific
+				drawStaticMessage(kTextkLampOn);
+			else if (_inventory[curInv]._quantity > 1) {
+				Common::String roomMessage = _inventory[curInv]._name + "  (" + Common::String::format("%d", _inventory[curInv]._quantity) + ")";
+				_graphics->drawMessage(roomMessage.c_str(), false);
+			} else
+				_graphics->drawMessage(_inventory[curInv]._name.c_str(), false);
+		}
+	} else
+		drawDirection(closePtr);
+
+	_lastTooLong = _graphics->_lastMessageLong;
+}
+
+void LabEngine::freeScreens() {
+	for (int i = 0; i < 20; i++) {
+		delete _moveImages[i];
+		_moveImages[i] = nullptr;
+	}
+
+	for (int imgIdx = 0; imgIdx < 10; imgIdx++) {
+		delete _invImages[imgIdx];
+		_invImages[imgIdx] = nullptr;
+	}
+}
+
+void LabEngine::perFlipButton(uint16 buttonId) {
+	for (ButtonList::iterator button = _moveButtonList.begin(); button != _moveButtonList.end(); ++button) {
+		Button *topButton = *button;
+		if (topButton->_buttonId == buttonId) {
+			Image *tmpImage = topButton->_image;
+			topButton->_image = topButton->_altImage;
+			topButton->_altImage = tmpImage;
+
+			if (!_alternate) {
+				_event->mouseHide();
+				topButton->_image->drawImage(topButton->_x, topButton->_y);
+				_event->mouseShow();
+			}
+
+			break;
+		}
+	}
+}
+
+void LabEngine::eatMessages() {
+	IntuiMessage *msg;
+
+	do {
+		msg = _event->getMsg();
+	} while (msg && !g_engine->shouldQuit());
+}
+
+bool LabEngine::doCloseUp(CloseDataPtr closePtr) {
+	if (!closePtr)
+		return false;
+
+	int luteRight;
+	Common::Rect textRect;
+
+	if (getPlatform() != Common::kPlatformWindows) {
+		textRect.left = 0;
+		textRect.right = 319;
+		textRect.top = 0;
+		textRect.bottom = 165;
+		luteRight = 124;
+	} else {
+		textRect.left = 2;
+		textRect.right = 317;
+		textRect.top = 2;
+		textRect.bottom = 165;
+		luteRight = 128;
+	}
+
+	switch (closePtr->_closeUpType) {
+	case kMonitorMuseum:
+	case kMonitorLibrary:
+	case kMonitorWindow:
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorGramophone:
+		textRect.right = 171;
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorUnicycle:
+		textRect.left = 100;
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorStatue:
+		textRect.left = 117;
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorTalisman:
+		textRect.right = 184;
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorLute:
+		textRect.right = luteRight;
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorClock:
+		textRect.right = 206;
+		doMonitor(closePtr->_graphicName, closePtr->_message, false, textRect);
+		break;
+	case kMonitorTerminal:
+		doMonitor(closePtr->_graphicName, closePtr->_message, true, textRect);
+		break;
+	default:
+		return false;
+	}
+
+	_curFileName = " ";
+	_graphics->drawPanel();
+
+	return true;
+}
+
+Common::String LabEngine::getInvName(uint16 curInv) {
+	if (_mainDisplay)
+		return _inventory[curInv]._bitmapName;
+
+	if ((curInv == kItemLamp) && _conditions->in(kCondLampOn))
+		return "P:Mines/120";
+
+	if ((curInv == kItemBelt) && _conditions->in(kCondBeltGlowing))
+		return "P:Future/kCondBeltGlowing";
+
+	if (curInv == kItemWestPaper) {
+		_curFileName = _inventory[curInv]._bitmapName;
+		_anim->_noPalChange = true;
+		_graphics->readPict(_curFileName, false);
+		_anim->_noPalChange = false;
+		doWestPaper();
+	} else if (curInv == kItemNotes) {
+		_curFileName = _inventory[curInv]._bitmapName;
+		_anim->_noPalChange = true;
+		_graphics->readPict(_curFileName, false);
+		_anim->_noPalChange = false;
+		doNotes();
+	}
+
+	return _inventory[curInv]._bitmapName;
+}
+
+void LabEngine::interfaceOff() {
+	if (!_interfaceOff) {
+		_event->attachButtonList(nullptr);
+		_event->mouseHide();
+		_interfaceOff = true;
+	}
+}
+
+void LabEngine::interfaceOn() {
+	if (_interfaceOff) {
+		_interfaceOff = false;
+		_event->mouseShow();
+	}
+
+	if (_graphics->_longWinInFront)
+		_event->attachButtonList(nullptr);
+	else if (_alternate)
+		_event->attachButtonList(&_invButtonList);
+	else
+		_event->attachButtonList(&_moveButtonList);
+}
+
+bool LabEngine::doUse(uint16 curInv) {
+	switch (curInv) {
+	case kItemMap:
+		drawStaticMessage(kTextUseMap);
+		interfaceOff();
+		_anim->stopDiff();
+		_curFileName = " ";
+		_closeDataPtr = nullptr;
+		doMap(_roomNum);
+		_graphics->setPalette(initColors, 8);
+		_graphics->drawMessage(nullptr, false);
+		_graphics->drawPanel();
+		return true;
+	case kItemJournal:
+		drawStaticMessage(kTextUseJournal);
+		interfaceOff();
+		_anim->stopDiff();
+		_curFileName = " ";
+		_closeDataPtr = nullptr;
+		doJournal();
+		_graphics->drawPanel();
+		_graphics->drawMessage(nullptr, false);
+		return true;
+	case kItemLamp:
+		interfaceOff();
+
+		if (_conditions->in(kCondLampOn)) {
+			drawStaticMessage(kTextTurnLampOff);
+			_conditions->exclElement(kCondLampOn);
+		} else {
+			drawStaticMessage(kTextTurnkLampOn);
+			_conditions->inclElement(kCondLampOn);
+		}
+
+		_anim->_doBlack = false;
+		_anim->_waitForEffect = true;
+		_graphics->readPict("Music:Click");
+		_anim->_waitForEffect = false;
+
+		_anim->_doBlack = false;
+		_nextFileName = getInvName(curInv);
+		return true;
+	case kItemBelt:
+		if (!_conditions->in(kCondBeltGlowing))
+			_conditions->inclElement(kCondBeltGlowing);
+
+		_anim->_doBlack = false;
+		_nextFileName = getInvName(curInv);
+		return true;
+	case kItemWhiskey:
+		_conditions->inclElement(kCondUsedHelmet);
+		drawStaticMessage(kTextUseWhiskey);
+		return true;
+	case kItemPithHelmet:
+		_conditions->inclElement(kCondUsedHelmet);
+		drawStaticMessage(kTextUsePith);
+		return true;
+	case kItemHelmet:
+		_conditions->inclElement(kCondUsedHelmet);
+		drawStaticMessage(kTextUseHelmet);
+		return true;
+	default:
+		return false;
+	}
+}
+
+void LabEngine::decIncInv(uint16 *curInv, bool decreaseFl) {
+	int8 step = (decreaseFl) ? -1 : 1;
+	uint newInv = *curInv + step;
+
+	// Handle wrapping
+	if (newInv < 1)
+		newInv = _numInv;
+	if (newInv > _numInv)
+		newInv = 1;
+
+	interfaceOff();
+	
+	while (newInv && (newInv <= _numInv)) {
+		if (_conditions->in(newInv) && !_inventory[newInv]._bitmapName.empty()) {
+			_nextFileName = getInvName(newInv);
+			*curInv = newInv;
+			break;
+		}
+
+		newInv += step;
+
+		// Handle wrapping
+		if (newInv < 1)
+			newInv = _numInv;
+		if (newInv > _numInv)
+			newInv = 1;
+	}
+}
+
+void LabEngine::mainGameLoop() {
+	uint16 actionMode = 4;
+	uint16 curInv = kItemMap;
+
+	bool forceDraw = false;
+	bool gotMessage = true;
+
+	_graphics->setPalette(initColors, 8);
+
+	_closeDataPtr = nullptr;
+	_roomNum = 1;
+	_direction = NORTH;
+
+	_resource->readRoomData("LAB:Doors");
+	if (!(_inventory = _resource->readInventory("LAB:Inventor")))
+		return;
+
+	if (!(_conditions = new LargeSet(_highestCondition + 1, this)))
+		return;
+
+	if (!(_roomsFound = new LargeSet(_manyRooms + 1, this)))
+		return;
+
+	_conditions->readInitialConditions("LAB:Conditio");
+
+	_graphics->_longWinInFront = false;
+	_graphics->drawPanel();
+
+	perFlipButton(actionMode);
+
+	// Set up initial picture.
+	while (1) {
+		_event->processInput();
+		_system->delayMillis(10);
+
+		if (gotMessage) {
+			if (_quitLab || g_engine->shouldQuit()) {
+				_anim->stopDiff();
+				break;
+			}
+
+			_music->resumeBackMusic();
+
+			// Sees what kind of close up we're in and does the appropriate stuff, if any.
+			if (doCloseUp(_closeDataPtr)) {
+				_closeDataPtr = nullptr;
+				mayShowCrumbIndicator();
+				_graphics->screenUpdate();
+			}
+
+			// Sets the current picture properly on the screen
+			if (_mainDisplay)
+				_nextFileName = getPictName(&_closeDataPtr);
+
+			if (_noUpdateDiff) {
+				// Potentially entered another room
+				_roomsFound->inclElement(_roomNum);
+				forceDraw |= (_nextFileName != _curFileName);
+
+				_noUpdateDiff = false;
+				_curFileName = _nextFileName;
+			} else if (_nextFileName != _curFileName) {
+				interfaceOff();
+				// Potentially entered another room
+				_roomsFound->inclElement(_roomNum);
+				_curFileName = _nextFileName;
+
+				if (_closeDataPtr) {
+					switch (_closeDataPtr->_closeUpType) {
+					case SPECIALLOCK:
+						if (_mainDisplay)
+							_tilePuzzle->showCombination(_curFileName);
+						break;
+					case SPECIALBRICK:
+					case SPECIALBRICKNOMOUSE:
+						if (_mainDisplay)
+							_tilePuzzle->showTile(_curFileName, (_closeDataPtr->_closeUpType == SPECIALBRICKNOMOUSE));
+						break;
+					default:
+						_graphics->readPict(_curFileName, false);
+						break;
+					}
+				} else
+					_graphics->readPict(_curFileName, false);
+
+				drawRoomMessage(curInv, _closeDataPtr);
+				forceDraw = false;
+
+				mayShowCrumbIndicator();
+				_graphics->screenUpdate();
+
+				if (!_followingCrumbs)
+					eatMessages();
+			}
+
+			if (forceDraw) {
+				drawRoomMessage(curInv, _closeDataPtr);
+				forceDraw = false;
+				_graphics->screenUpdate();
+			}
+		}
+
+		// Make sure we check the music at least after every message
+		updateMusicAndEvents();
+		interfaceOn();
+		IntuiMessage *curMsg = _event->getMsg();
+		if (g_engine->shouldQuit()) {
+			_quitLab = true;
+			return;
+		}
+
+		if (!curMsg) {
+			// Does music load and next animation frame when you've run out of messages
+			gotMessage = false;
+			_music->checkRoomMusic();
+			updateMusicAndEvents();
+			_anim->diffNextFrame();
+
+			if (_followingCrumbs) {
+				int result = followCrumbs();
+
+				if (result != 0) {
+					uint16 code = 0;
+					switch (result) {
+					case VKEY_UPARROW:
+						code = kButtonForward;
+						break;
+					case VKEY_LTARROW:
+						code = kButtonLeft;
+						break;
+					case VKEY_RTARROW:
+						code = kButtonRight;
+						break;
+					default:
+						break;
+					}
+
+					gotMessage = true;
+					mayShowCrumbIndicator();
+					_graphics->screenUpdate();
+					if (!fromCrumbs(kMessageButtonUp, code, 0, _event->updateAndGetMousePos(), curInv, curMsg, forceDraw, code, actionMode))
+						break;
+				}
+			}
+
+			mayShowCrumbIndicator();
+			_graphics->screenUpdate();
+		} else {
+			gotMessage = true;
+			_followingCrumbs = false;
+			if (!fromCrumbs(curMsg->_msgClass, curMsg->_code, curMsg->_qualifier, curMsg->_mouse, curInv, curMsg, forceDraw, curMsg->_code, actionMode))
+				break;
+		}
+	}
+}
+
+void LabEngine::showLab2Teaser() {
+	_graphics->blackAllScreen();
+	_graphics->readPict("P:End/L2In.1");
+
+	for (int i = 0; i < 120; i++) {
+		updateMusicAndEvents();
+		waitTOF();
+	}
+
+	_graphics->readPict("P:End/L2In.9");
+	_graphics->readPict("P:End/Lost");
+
+	while (!_event->getMsg() && !shouldQuit()) {
+		updateMusicAndEvents();
+		_anim->diffNextFrame();
+		waitTOF();
+	}
+}
+
+bool LabEngine::fromCrumbs(uint32 tmpClass, uint16 code, uint16 qualifier, Common::Point tmpPos,
+			uint16 &curInv, IntuiMessage *curMsg, bool &forceDraw, uint16 buttonId, uint16 &actionMode) {
+	uint32 msgClass = tmpClass;
+	Common::Point curPos = tmpPos;
+
+	uint16 oldDirection = 0;
+	uint16 lastInv = kItemMap;
+	CloseDataPtr wrkClosePtr = nullptr;
+	bool leftButtonClick = false;
+	bool rightButtonClick = false;
+
+	_anim->_doBlack = false;
+
+	if (g_engine->shouldQuit())
+		return false;
+
+	if ((msgClass == kMessageRawKey) && !_graphics->_longWinInFront) {
+		if (!processKey(curMsg, msgClass, qualifier, curPos, curInv, forceDraw, code))
+			return false;
+	}
+
+	leftButtonClick = (msgClass == kMessageLeftClick);
+	rightButtonClick = (msgClass == kMessageRightClick);
+
+	if (_graphics->_longWinInFront) {
+		if ((msgClass == kMessageRawKey) || (leftButtonClick || rightButtonClick)) {
+			_graphics->_longWinInFront = false;
+			_graphics->drawPanel();
+			drawRoomMessage(curInv, _closeDataPtr);
+			_graphics->screenUpdate();
+		}
+	} else if ((msgClass == kMessageButtonUp) && !_alternate) {
+		processMainButton(curInv, lastInv, oldDirection, forceDraw, buttonId, actionMode);
+	} else if ((msgClass == kMessageButtonUp) && _alternate) {
+		processAltButton(curInv, lastInv, buttonId, actionMode);
+	} else if (leftButtonClick && _mainDisplay) {
+		interfaceOff();
+		_mainDisplay = true;
+
+		if (_closeDataPtr) {
+			switch (_closeDataPtr->_closeUpType) {
+			case SPECIALLOCK:
+				if (_mainDisplay)
+					_tilePuzzle->mouseCombination(curPos);
+				break;
+			case SPECIALBRICK:
+				if (_mainDisplay)
+					_tilePuzzle->mouseTile(curPos);
+				break;
+			default:
+				performAction(actionMode, curPos, curInv);
+				break;
+			}
+		} else
+			performAction(actionMode, curPos, curInv);
+
+		mayShowCrumbIndicator();
+		_graphics->screenUpdate();
+	} else if (rightButtonClick) {
+		eatMessages();
+		_alternate = !_alternate;
+		_anim->_doBlack = true;
+		_mainDisplay = true;
+		// Sets the correct button list
+		interfaceOn();
+
+		if (_alternate) {
+			if (lastInv && _conditions->in(lastInv))
+				curInv = lastInv;
+			else
+				decIncInv(&curInv, false);
+		}
+
+		_graphics->drawPanel();
+		drawRoomMessage(curInv, _closeDataPtr);
+
+		mayShowCrumbIndicator();
+		_graphics->screenUpdate();
+	} else if (msgClass == kMessageDeltaMove) {
+		ViewData *vptr = getViewData(_roomNum, _direction);
+		CloseDataPtr oldClosePtr = vptr->_closeUps;
+		CloseDataPtr tmpClosePtr = _closeDataPtr;
+		setCurrentClose(curPos, &tmpClosePtr, true);
+
+		if (!tmpClosePtr || (tmpClosePtr == _closeDataPtr)) {
+			if (!_closeDataPtr)
+				wrkClosePtr = oldClosePtr;
+			else
+				wrkClosePtr = _closeDataPtr->_subCloseUps;
+		} else
+			wrkClosePtr = tmpClosePtr->_nextCloseUp;
+
+
+		if (!wrkClosePtr) {
+			if (!_closeDataPtr)
+				wrkClosePtr = oldClosePtr;
+			else
+				wrkClosePtr = _closeDataPtr->_subCloseUps;
+		}
+
+		if (wrkClosePtr)
+			_event->setMousePos(Common::Point(_utils->scaleX((wrkClosePtr->_x1 + wrkClosePtr->_x2) / 2), _utils->scaleY((wrkClosePtr->_y1 + wrkClosePtr->_y2) / 2)));
+	}
+
+	return true;
+}
+
+bool LabEngine::processKey(IntuiMessage *curMsg, uint32 &msgClass, uint16 &qualifier, Common::Point &curPos, uint16 &curInv, bool &forceDraw, uint16 code) {
+	if (code == Common::KEYCODE_RETURN) {
+		// The return key
+		msgClass = kMessageLeftClick;
+		qualifier = 0;
+		curPos = _event->getMousePos();
+	} else if ((getPlatform() == Common::kPlatformWindows) && (code == Common::KEYCODE_b)) {
+		// Start bread crumbs
+		_breadCrumbs[0]._roomNum = 0;
+		_numCrumbs = 0;
+		_droppingCrumbs = true;
+		mayShowCrumbIndicator();
+		_graphics->screenUpdate();
+	} else if ((code == Common::KEYCODE_f) || (code == Common::KEYCODE_r)) {
+		// Follow bread crumbs
+		if (_droppingCrumbs) {
+			if (_numCrumbs > 0) {
+				_followingCrumbs = true;
+				_followCrumbsFast = (code == Common::KEYCODE_r);
+				_isCrumbTurning = false;
+				_isCrumbWaiting = false;
+				_crumbTimestamp = _system->getMillis();
+
+				if (_alternate) {
+					eatMessages();
+					_alternate = false;
+					_anim->_doBlack = true;
+
+					_mainDisplay = true;
+					// Sets the correct button list
+					interfaceOn();
+					_graphics->drawPanel();
+					drawRoomMessage(curInv, _closeDataPtr);
+					_graphics->screenUpdate();
+				}
+			} else {
+				_breadCrumbs[0]._roomNum = 0;
+				_droppingCrumbs = false;
+
+				// Need to hide indicator!!!!
+				mayShowCrumbIndicatorOff();
+				_graphics->screenUpdate();
+			}
+		}
+	} else if ((code == Common::KEYCODE_x) || (code == Common::KEYCODE_q)) {
+		// Quit?
+		_graphics->drawMessage("Do you want to quit? (Y/N)", false);
+		eatMessages();
+		interfaceOff();
+
+		while (1) {
+			// Make sure we check the music at least after every message
+			updateMusicAndEvents();
+			curMsg = _event->getMsg();
+
+			if (g_engine->shouldQuit())
+				return false;
+
+			if (!curMsg) {
+				// Does music load and next animation frame when you've run out of messages
+				updateMusicAndEvents();
+				_anim->diffNextFrame();
+			} else if (curMsg->_msgClass == kMessageRawKey) {
+				if ((curMsg->_code == Common::KEYCODE_y) || (curMsg->_code == Common::KEYCODE_q)) {
+					_anim->stopDiff();
+					return false;
+				} else if (curMsg->_code < 128)
+					break;
+			} else if ((curMsg->_msgClass == kMessageLeftClick) || (curMsg->_msgClass == kMessageRightClick))
+				break;
+		}
+
+		forceDraw = true;
+		interfaceOn();
+	} else if (code == Common::KEYCODE_TAB)
+		msgClass = kMessageDeltaMove;
+	else if (code == Common::KEYCODE_ESCAPE)
+		_closeDataPtr = nullptr;
+
+	eatMessages();
+
+	return true;
+}
+
+void LabEngine::processMainButton(uint16 &curInv, uint16 &lastInv, uint16 &oldDirection, bool &forceDraw, uint16 buttonId, uint16 &actionMode) {
+	uint16 newDir;
+	uint16 oldRoomNum;
+
+	switch (buttonId) {
+	case kButtonPickup:
+	case kButtonUse:
+	case kButtonOpen:
+	case kButtonClose:
+	case kButtonLook:
+		if ((actionMode == 4) && (buttonId == kButtonLook) && _closeDataPtr) {
+			doMainView(&_closeDataPtr);
+
+			_anim->_doBlack = true;
+			_closeDataPtr = nullptr;
+			mayShowCrumbIndicator();
+		} else {
+			uint16 oldActionMode = actionMode;
+			actionMode = buttonId;
+
+			if (oldActionMode < 5)
+				perFlipButton(oldActionMode);
+
+			perFlipButton(actionMode);
+			drawStaticMessage(kTextTakeWhat + buttonId);
+		}
+		break;
+	case kButtonInventory:
+		eatMessages();
+
+		_alternate = true;
+		_anim->_doBlack = true;
+		// Sets the correct button list
+		interfaceOn();
+		_mainDisplay = false;
+
+		if (lastInv && _conditions->in(lastInv)) {
+			curInv = lastInv;
+			_nextFileName = getInvName(curInv);
+		} else
+			decIncInv(&curInv, false);
+
+		_graphics->drawPanel();
+		drawRoomMessage(curInv, _closeDataPtr);
+
+		mayShowCrumbIndicator();
+		break;
+
+	case kButtonLeft:
+	case kButtonRight:
+		_closeDataPtr = nullptr;
+		if (buttonId == kButtonLeft)
+			drawStaticMessage(kTextTurnLeft);
+		else
+			drawStaticMessage(kTextTurnRight);
+
+		_curFileName = " ";
+		oldDirection = _direction;
+
+		newDir = processArrow(_direction, buttonId - 6);
+		doTurn(_direction, newDir, &_closeDataPtr);
+		_anim->_doBlack = true;
+		_direction = newDir;
+		forceDraw = true;
+		mayShowCrumbIndicator();
+		break;
+
+	case kButtonForward:
+		_closeDataPtr = nullptr;
+		oldRoomNum = _roomNum;
+
+		if (doGoForward(&_closeDataPtr)) {
+			if (oldRoomNum == _roomNum)
+				_anim->_doBlack = true;
+		} else {
+			_anim->_doBlack = true;
+			_direction = processArrow(_direction, buttonId - 6);
+
+			if (oldRoomNum != _roomNum) {
+				drawStaticMessage(kTextGoForward);
+				// Potentially entered a new room
+				_roomsFound->inclElement(_roomNum);
+				_curFileName = " ";
+				forceDraw = true;
+			} else {
+				_anim->_doBlack = true;
+				drawStaticMessage(kTextNoPath);
+			}
+		}
+
+		if (_followingCrumbs) {
+			if (_isCrumbTurning) {
+				if (_direction == oldDirection)
+					_followingCrumbs = false;
+			} else if (_roomNum == oldRoomNum) { // didn't get there?
+				_followingCrumbs = false;
+			}
+		} else if (_droppingCrumbs && (oldRoomNum != _roomNum)) {
+			// If in surreal maze, turn off DroppingCrumbs.
+			if ((_roomNum >= 245) && (_roomNum <= 280)) {
+				_followingCrumbs = false;
+				_droppingCrumbs = false;
+				_numCrumbs = 0;
+				_breadCrumbs[0]._roomNum = 0;
+			} else {
+				bool intersect = false;
+				for (int idx = 0; idx < _numCrumbs; idx++) {
+					if (_breadCrumbs[idx]._roomNum == _roomNum) {
+						_numCrumbs = idx + 1;
+						_breadCrumbs[_numCrumbs]._roomNum = 0;
+						intersect = true;
+					}
+				}
+
+				if (!intersect) {
+					if (_numCrumbs == MAX_CRUMBS) {
+						_numCrumbs = MAX_CRUMBS - 1;
+						memcpy(&_breadCrumbs[0], &_breadCrumbs[1], _numCrumbs * sizeof _breadCrumbs[0]);
+					}
+
+					_breadCrumbs[_numCrumbs]._roomNum = _roomNum;
+					_breadCrumbs[_numCrumbs++]._direction = _direction;
+				}
+			}
+		}
+
+		mayShowCrumbIndicator();
+		break;
+	case kButtonMap:
+		doUse(kItemMap);
+
+		mayShowCrumbIndicator();
+		break;
+	}
+
+	_graphics->screenUpdate();
+}
+
+void LabEngine::processAltButton(uint16 &curInv, uint16 &lastInv, uint16 buttonId, uint16 &actionMode) {
+	bool saveRestoreSuccessful = true;
+
+	_anim->_doBlack = true;
+
+	switch (buttonId) {
+	case kButtonMainDisplay:
+		eatMessages();
+		_alternate = false;
+		_anim->_doBlack = true;
+
+		_mainDisplay = true;
+		// Sets the correct button list
+		interfaceOn();
+		_graphics->drawPanel();
+		drawRoomMessage(curInv, _closeDataPtr);
+		break;
+
+	case kButtonSaveLoad:
+		interfaceOff();
+		_anim->stopDiff();
+		_curFileName = " ";
+
+		saveRestoreSuccessful = saveRestoreGame();
+		_closeDataPtr = nullptr;
+		_mainDisplay = true;
+
+		curInv = lastInv = kItemMap;
+		_nextFileName = getInvName(curInv);
+
+		_graphics->drawPanel();
+
+		if (!saveRestoreSuccessful) {
+			_graphics->drawMessage("Save/restore aborted", false);
+			_graphics->setPalette(initColors, 8);
+			_system->delayMillis(1000);
+		}
+		break;
+
+	case kButtonUseItem:
+		if (!doUse(curInv)) {
+			uint16 oldActionMode = actionMode;
+			// Use button
+			actionMode = 5;
+
+			if (oldActionMode < 5)
+				perFlipButton(oldActionMode);
+
+			drawStaticMessage(kTextUseOnWhat);
+			_mainDisplay = true;
+		}
+		break;
+
+	case kButtonLookAtItem:
+		_mainDisplay = !_mainDisplay;
+
+		if ((curInv == 0) || (curInv > _numInv)) {
+			curInv = 1;
+
+			while ((curInv <= _numInv) && !_conditions->in(curInv))
+				curInv++;
+		}
+
+		if ((curInv <= _numInv) && _conditions->in(curInv) && !_inventory[curInv]._bitmapName.empty())
+			_nextFileName = getInvName(curInv);
+
+		break;
+
+	case kButtonPrevItem:
+		decIncInv(&curInv, true);
+		lastInv = curInv;
+		drawRoomMessage(curInv, _closeDataPtr);
+		break;
+
+	case kButtonNextItem:
+		decIncInv(&curInv, false);
+		lastInv = curInv;
+		drawRoomMessage(curInv, _closeDataPtr);
+		break;
+
+	case kButtonBreadCrumbs:
+		_breadCrumbs[0]._roomNum = 0;
+		_numCrumbs = 0;
+		_droppingCrumbs = true;
+		mayShowCrumbIndicator();
+		break;
+
+	case kButtonFollowCrumbs:
+		if (_droppingCrumbs) {
+			if (_numCrumbs > 0) {
+				_followingCrumbs = true;
+				_followCrumbsFast = false;
+				_isCrumbTurning = false;
+				_isCrumbWaiting = false;
+				_crumbTimestamp = _system->getMillis();
+
+				eatMessages();
+				_alternate = false;
+				_anim->_doBlack = true;
+
+				_mainDisplay = true;
+				// Sets the correct button list
+				interfaceOn();
+				_graphics->drawPanel();
+				drawRoomMessage(curInv, _closeDataPtr);
+			} else {
+				_breadCrumbs[0]._roomNum = 0;
+				_droppingCrumbs = false;
+
+				// Need to hide indicator!!!!
+				mayShowCrumbIndicatorOff();
+			}
+		}
+		break;
+	}
+
+	_graphics->screenUpdate();
+}
+
+void LabEngine::performAction(uint16 actionMode, Common::Point curPos, uint16 &curInv) {
+	eatMessages();
+
+	switch (actionMode) {
+	case 0:
+		// Take something.
+		if (doActionRule(curPos, actionMode, _roomNum, &_closeDataPtr))
+			_curFileName = _newFileName;
+		else if (takeItem(curPos, &_closeDataPtr))
+			drawStaticMessage(kTextTakeItem);
+		else if (doActionRule(curPos, kRuleActionTakeDef, _roomNum, &_closeDataPtr))
+			_curFileName = _newFileName;
+		else if (doActionRule(curPos, kRuleActionTake, 0, &_closeDataPtr))
+			_curFileName = _newFileName;
+		else if (curPos.y < (_utils->vgaScaleY(149) + _utils->svgaCord(2)))
+			drawStaticMessage(kTextNothing);
+
+		break;
+
+	case 1:
+	case 2:
+	case 3:
+		// Manipulate an object, Open up a "door" or Close a "door"
+		if (doActionRule(curPos, actionMode, _roomNum, &_closeDataPtr))
+			_curFileName = _newFileName;
+		else if (!doActionRule(curPos, actionMode, 0, &_closeDataPtr)) {
+			if (curPos.y < (_utils->vgaScaleY(149) + _utils->svgaCord(2)))
+				drawStaticMessage(kTextNothing);
+		}
+		break;
+
+	case 4: {
+		// Look at closeups
+		CloseDataPtr tmpClosePtr = _closeDataPtr;
+		setCurrentClose(curPos, &tmpClosePtr, true);
+
+		if (_closeDataPtr == tmpClosePtr) {
+			if (curPos.y < (_utils->vgaScaleY(149) + _utils->svgaCord(2)))
+				drawStaticMessage(kTextNothing);
+		} else if (!tmpClosePtr->_graphicName.empty()) {
+			_anim->_doBlack = true;
+			_closeDataPtr = tmpClosePtr;
+		} else if (curPos.y < (_utils->vgaScaleY(149) + _utils->svgaCord(2)))
+			drawStaticMessage(kTextNothing);
+	}
+			break;
+
+	case 5:
+		if (_conditions->in(curInv)) {
+			// Use an item on something else
+			if (doOperateRule(curPos, curInv, &_closeDataPtr)) {
+				_curFileName = _newFileName;
+
+				if (!_conditions->in(curInv))
+					decIncInv(&curInv, false);
+			}
+			else if (curPos.y < (_utils->vgaScaleY(149) + _utils->svgaCord(2)))
+				drawStaticMessage(kTextNothing);
+		}
+	}
+}
+
+void LabEngine::go() {
+	_isHiRes = ((getFeatures() & GF_LOWRES) == 0);
+	_graphics->setUpScreens();
+
+	_event->initMouse();
+	if (_msgFont)
+		_graphics->closeFont(&_msgFont);
+
+	if (getPlatform() != Common::kPlatformAmiga)
+		_msgFont = _resource->getFont("F:AvanteG.12");
+	else
+		_msgFont = _resource->getFont("F:Map.fon");
+	_event->mouseHide();
+
+	Intro *intro = new Intro(this);
+	intro->introSequence();
+	delete intro;
+
+	_event->mouseShow();
+	mainGameLoop();
+
+	_graphics->closeFont(&_msgFont);
+	_graphics->freePict();
+
+	freeScreens();
+
+	_music->freeMusic();
+}
+
+int LabEngine::followCrumbs() {
+	// NORTH, SOUTH, EAST, WEST
+	int movement[4][4] = {
+		{ VKEY_UPARROW, VKEY_RTARROW, VKEY_RTARROW, VKEY_LTARROW },
+		{ VKEY_RTARROW, VKEY_UPARROW, VKEY_LTARROW, VKEY_RTARROW },
+		{ VKEY_LTARROW, VKEY_RTARROW, VKEY_UPARROW, VKEY_RTARROW },
+		{ VKEY_RTARROW, VKEY_LTARROW, VKEY_RTARROW, VKEY_UPARROW }
+	};
+
+	if (_isCrumbWaiting) {
+		if (_system->getMillis() <= _crumbTimestamp)
+			return 0;
+
+		_isCrumbWaiting = false;
+	}
+
+	if (!_isCrumbTurning)
+		_breadCrumbs[_numCrumbs--]._roomNum = 0;
+
+	// Is the current crumb this room? If not, logic error.
+	if (_roomNum != _breadCrumbs[_numCrumbs]._roomNum) {
+		_numCrumbs = 0;
+		_breadCrumbs[0]._roomNum = 0;
+		_droppingCrumbs = false;
+		_followingCrumbs = false;
+		return 0;
+	}
+
+	int exitDir;
+	// which direction is last crumb
+	if (_breadCrumbs[_numCrumbs]._direction == EAST)
+		exitDir = WEST;
+	else if (_breadCrumbs[_numCrumbs]._direction == WEST)
+		exitDir = EAST;
+	else if (_breadCrumbs[_numCrumbs]._direction == NORTH)
+		exitDir = SOUTH;
+	else
+		exitDir = NORTH;
+
+	int moveDir = movement[_direction][exitDir];
+
+	if (_numCrumbs == 0) {
+		_isCrumbTurning = false;
+		_breadCrumbs[0]._roomNum = 0;
+		_droppingCrumbs = false;
+		_followingCrumbs = false;
+	} else {
+		_isCrumbTurning = (moveDir != VKEY_UPARROW);
+		_isCrumbWaiting = true;
+
+		int theDelay = (_followCrumbsFast ? 1000 / 4 : 1000);
+		_crumbTimestamp = theDelay + _system->getMillis();
+	}
+
+	return moveDir;
+}
+
+
+void LabEngine::mayShowCrumbIndicator() {
+	static Image dropCrumbsImage(24, 24, nullptr, this);
+	if (getPlatform() != Common::kPlatformWindows)
+		return;
+
+	if (_droppingCrumbs && _mainDisplay) {
+		_event->mouseHide();
+		dropCrumbsImage.drawMaskImage(612, 4);
+		_event->mouseShow();
+	}
+}
+
+void LabEngine::mayShowCrumbIndicatorOff() {
+	static Image dropCrumbsOffImage(24, 24, nullptr, this);
+
+	if (getPlatform() != Common::kPlatformWindows)
+		return;
+
+	if (_mainDisplay) {
+		_event->mouseHide();
+		dropCrumbsOffImage.drawMaskImage(612, 4);
+		_event->mouseShow();
+	}
+}
+
+} // End of namespace Lab