4 files changed, 246 insertions, 9 deletions

diff --git a/src/control/AutoPilot.h b/src/control/AutoPilot.h
index 4043c4e5..3b63a143 100644
--- a/src/control/AutoPilot.h
+++ b/src/control/AutoPilot.h
@@ -60,9 +60,9 @@ enum eCarDrivingStyle : uint8
 
 class CAutoPilot {
 public:
-	uint32 m_nCurrentRouteNode;
-	uint32 m_nNextRouteNode;
-	uint32 m_nPrevRouteNode;
+	int32 m_nCurrentRouteNode;
+	int32 m_nNextRouteNode;
+	int32 m_nPrevRouteNode;
 	uint32 m_nTimeEnteredCurve;
 	uint32 m_nTimeToSpendOnCurrentCurve;
 	uint32 m_nCurrentPathNodeInfo;
@@ -83,8 +83,8 @@ public:
 	uint8 m_nCruiseSpeed;
 	uint8 m_bSlowedDownBecauseOfCars : 1;
 	uint8 m_bSlowedDownBecauseOfPeds : 1;
-	uint8 m_flag4 : 1;
-	uint8 m_flag8 : 1;
+	uint8 m_bStayInCurrentLevel : 1;
+	uint8 m_bStayInFastLane : 1;
 	uint8 m_flag10 : 1;
 	CVector m_vecDestinationCoors;
 	void *m_aPathFindNodesInfo[8];
@@ -114,7 +114,7 @@ public:
 		m_pTargetCar = 0;
 		m_nTimeToStartMission = CTimer::GetTimeInMilliseconds();
 		m_nAntiReverseTimer = m_nTimeToStartMission;
-		m_flag8 = false;
+		m_bStayInFastLane = false;
 	}
 
 	void ModifySpeed(float);
diff --git a/src/control/CarCtrl.cpp b/src/control/CarCtrl.cpp
index 1f298fd5..dc3500d3 100644
--- a/src/control/CarCtrl.cpp
+++ b/src/control/CarCtrl.cpp
@@ -45,6 +45,11 @@
 #define OBJECT_WIDTH_TO_WEAVE 0.3f
 #define PED_WIDTH_TO_WEAVE 0.8f
 
+#define PATH_DIRECTION_NONE 0
+#define PATH_DIRECTION_STRAIGHT 1
+#define PATH_DIRECTION_RIGHT 2
+#define PATH_DIRECTION_LEFT 4
+
 int &CCarCtrl::NumLawEnforcerCars = *(int*)0x8F1B38;
 int &CCarCtrl::NumAmbulancesOnDuty = *(int*)0x885BB0;
 int &CCarCtrl::NumFiretrucksOnDuty = *(int*)0x9411F0;
@@ -68,9 +73,9 @@ WRAPPER void CCarCtrl::JoinCarWithRoadSystem(CVehicle*) { EAXJMP(0x41F820); }
 WRAPPER void CCarCtrl::SteerAICarWithPhysics(CVehicle*) { EAXJMP(0x41DA60); }
 WRAPPER void CCarCtrl::RemoveFromInterestingVehicleList(CVehicle* v) { EAXJMP(0x41F7A0); }
 WRAPPER void CCarCtrl::GenerateEmergencyServicesCar(void) { EAXJMP(0x41FC50); }
-WRAPPER void CCarCtrl::PickNextNodeAccordingStrategy(CVehicle*) { EAXJMP(0x41BA50); }
 WRAPPER void CCarCtrl::DragCarToPoint(CVehicle*, CVector*) { EAXJMP(0x41D450); }
 WRAPPER void CCarCtrl::Init(void) { EAXJMP(0x41D280); }
+WRAPPER bool CCarCtrl::PickNextNodeToFollowPath(CVehicle*) { EAXJMP(0x41CD50); }
 
 void
 CCarCtrl::GenerateRandomCars()
@@ -1419,6 +1424,223 @@ void CCarCtrl::WeaveForObject(CEntity* pOtherEntity, CVehicle* pVehicle, float*
 	}
 }
 
+bool CCarCtrl::PickNextNodeAccordingStrategy(CVehicle* pVehicle)
+{
+	switch (pVehicle->AutoPilot.m_nCarMission){
+	case MISSION_RAMPLAYER_FARAWAY:
+	case MISSION_BLOCKPLAYER_FARAWAY:
+		PickNextNodeToChaseCar(pVehicle,
+			FindPlayerCoors().x,
+			FindPlayerCoors().y,
+#ifdef FIX_PATHFIND_BUG
+			FindPlayerCoors().z,
+#endif
+			FindPlayerVehicle());
+		return false;
+	case MISSION_GOTOCOORDS:
+	case MISSION_GOTOCOORDS_ACCURATE:
+		return PickNextNodeToFollowPath(pVehicle);
+	case MISSION_RAMCAR_FARAWAY:
+	case MISSION_BLOCKCAR_FARAWAY:
+		PickNextNodeToChaseCar(pVehicle,
+			pVehicle->AutoPilot.m_pTargetCar->GetPosition().x,
+			pVehicle->AutoPilot.m_pTargetCar->GetPosition().y,
+#ifdef FIX_PATHFIND_BUG
+			pVehicle->AutoPilot.m_pTargetCar->GetPosition().z,
+#endif
+			pVehicle->AutoPilot.m_pTargetCar);
+		return false;
+	default:
+		PickNextNodeRandomly(pVehicle);
+		return false;
+	}
+}
+
+void CCarCtrl::PickNextNodeRandomly(CVehicle* pVehicle)
+{
+	int32 prevNode = pVehicle->AutoPilot.m_nCurrentRouteNode;
+	int32 curNode = pVehicle->AutoPilot.m_nNextRouteNode;
+	uint8 totalLinks = ThePaths.m_pathNodes[curNode].numLinks;
+	CCarPathLink* pCurLink = &ThePaths.m_carPathLinks[pVehicle->AutoPilot.m_nNextPathNodeInfo];
+	uint8 lanesOnCurrentPath = pCurLink->pathNodeIndex == curNode ?
+		pCurLink->numRightLanes : pCurLink->numLeftLanes;
+	uint8 allowedDirections = PATH_DIRECTION_NONE;
+	uint8 nextLane = pVehicle->AutoPilot.m_nNextLane;
+	if (nextLane == 0)
+		/* We are always allowed to turn left from  leftmost lane */
+		allowedDirections |= PATH_DIRECTION_LEFT;
+	if (nextLane == lanesOnCurrentPath - 1)
+		/* We are always allowed to turn right from rightmost lane */
+		allowedDirections |= PATH_DIRECTION_RIGHT;
+	if (lanesOnCurrentPath < 3 || allowedDirections == PATH_DIRECTION_NONE)
+		/* We are always allowed to go straight on one/two-laned road */
+		/* or if we are in one of middle lanes of the road */
+		allowedDirections |= PATH_DIRECTION_STRAIGHT;
+	int attempt;
+	pVehicle->AutoPilot.m_nPrevRouteNode = pVehicle->AutoPilot.m_nCurrentRouteNode;
+	pVehicle->AutoPilot.m_nCurrentRouteNode = pVehicle->AutoPilot.m_nNextRouteNode;
+	CPathNode* pPrevPathNode = &ThePaths.m_pathNodes[prevNode];
+	CPathNode* pCurPathNode = &ThePaths.m_pathNodes[curNode];
+	int16 nextLink;
+	CCarPathLink* pNextLink;
+	CPathNode* pNextPathNode;
+	bool goingAgainstOneWayRoad;
+	uint8 direction;
+	for(attempt = 0; attempt < 15; attempt++){
+		if (attempt != 0){
+			if (pVehicle->AutoPilot.m_nNextRouteNode != prevNode){
+				if (direction & allowedDirections){
+					pNextPathNode = &ThePaths.m_pathNodes[pVehicle->AutoPilot.m_nNextRouteNode];
+					if ((!pNextPathNode->bDeadEnd || pPrevPathNode->bDeadEnd) &&
+						(!pNextPathNode->bDisabled || pPrevPathNode->bDisabled) &&
+						(!pNextPathNode->bBetweenLevels || pPrevPathNode->bBetweenLevels || !pVehicle->AutoPilot.m_bStayInCurrentLevel) &&
+						!goingAgainstOneWayRoad)
+						break;
+				}
+			}
+		}
+		nextLink = CGeneral::GetRandomNumber() % totalLinks;
+		pVehicle->AutoPilot.m_nNextRouteNode = ThePaths.m_connections[nextLink + pCurPathNode->firstLink];
+		direction = FindPathDirection(prevNode, curNode, pVehicle->AutoPilot.m_nNextRouteNode);
+		pNextLink = &ThePaths.m_carPathLinks[ThePaths.m_carPathConnections[nextLink + pCurPathNode->firstLink]];
+		goingAgainstOneWayRoad = pNextLink->pathNodeIndex == curNode ? pNextLink->numRightLanes == 0 : pNextLink->numLeftLanes == 0;
+	}
+	if (attempt >= 15) {
+		/* If we failed 15 times, then remove dead end and current lane limitations */
+		for (attempt = 0; attempt < 15; attempt++) {
+			if (attempt != 0) {
+				if (pVehicle->AutoPilot.m_nNextRouteNode != prevNode) {
+					pNextPathNode = &ThePaths.m_pathNodes[pVehicle->AutoPilot.m_nNextRouteNode];
+					if ((!pNextPathNode->bDisabled || pPrevPathNode->bDisabled) &&
+						(!pNextPathNode->bBetweenLevels || pNextPathNode->bBetweenLevels || !pVehicle->AutoPilot.m_bStayInCurrentLevel) &&
+						!goingAgainstOneWayRoad)
+						break;
+				}
+			}
+			nextLink = CGeneral::GetRandomNumber() % totalLinks;
+			pVehicle->AutoPilot.m_nNextRouteNode = ThePaths.m_connections[nextLink + pCurPathNode->firstLink];
+			pNextLink = &ThePaths.m_carPathLinks[ThePaths.m_carPathConnections[nextLink + pCurPathNode->firstLink]];
+			goingAgainstOneWayRoad = pNextLink->pathNodeIndex == curNode ? pNextLink->numRightLanes == 0 : pNextLink->numLeftLanes == 0;
+		}
+	}
+	if (attempt >= 15) {
+		/* If we failed again, remove no U-turn limitation and remove randomness */
+		for (nextLink = 0; nextLink < totalLinks; nextLink++) {
+			pVehicle->AutoPilot.m_nNextRouteNode = ThePaths.m_connections[nextLink + pCurPathNode->firstLink];
+			pNextLink = &ThePaths.m_carPathLinks[ThePaths.m_carPathConnections[nextLink + pCurPathNode->firstLink]];
+			goingAgainstOneWayRoad = pNextLink->pathNodeIndex == curNode ? pNextLink->numRightLanes == 0 : pNextLink->numLeftLanes == 0;
+			if (!goingAgainstOneWayRoad) {
+				pNextPathNode = &ThePaths.m_pathNodes[pVehicle->AutoPilot.m_nNextRouteNode];
+				if ((!pNextPathNode->bDisabled || pPrevPathNode->bDisabled) &&
+					(!pNextPathNode->bBetweenLevels || pNextPathNode->bBetweenLevels || !pVehicle->AutoPilot.m_bStayInCurrentLevel))
+					/* Nice way to exit loop but this will fail because this is used for indexing! */
+					nextLink = 1000;
+			}
+		}
+		if (nextLink < 999)
+			/* If everything else failed, turn vehicle around */
+			pVehicle->AutoPilot.m_nNextRouteNode = prevNode;
+	}
+	pNextPathNode = &ThePaths.m_pathNodes[pVehicle->AutoPilot.m_nNextRouteNode];
+	pNextLink = &ThePaths.m_carPathLinks[ThePaths.m_carPathConnections[nextLink + pCurPathNode->firstLink]];
+	if (prevNode == pVehicle->AutoPilot.m_nNextRouteNode){
+		/* We can no longer shift vehicle without physics if we have to turn it around. */
+		pVehicle->m_status = STATUS_PHYSICS;
+		SwitchVehicleToRealPhysics(pVehicle);
+	}
+	pVehicle->AutoPilot.m_nTimeEnteredCurve += pVehicle->AutoPilot.m_nTimeToSpendOnCurrentCurve;
+	pVehicle->AutoPilot.m_nPreviousPathNodeInfo = pVehicle->AutoPilot.m_nCurrentPathNodeInfo;
+	pVehicle->AutoPilot.m_nCurrentPathNodeInfo = pVehicle->AutoPilot.m_nNextPathNodeInfo;
+	pVehicle->AutoPilot.m_nPreviousDirection = pVehicle->AutoPilot.m_nCurrentDirection;
+	pVehicle->AutoPilot.m_nCurrentDirection = pVehicle->AutoPilot.m_nNextDirection;
+	pVehicle->AutoPilot.m_nCurrentLane = pVehicle->AutoPilot.m_nNextLane;
+	pVehicle->AutoPilot.m_nNextPathNodeInfo = ThePaths.m_carPathConnections[nextLink + pCurPathNode->firstLink];
+	uint8 lanesOnNextNode;
+	if (curNode >= pVehicle->AutoPilot.m_nNextRouteNode){
+		pVehicle->AutoPilot.m_nNextDirection = 1;
+		lanesOnNextNode = pNextLink->numLeftLanes;
+	}else{
+		pVehicle->AutoPilot.m_nNextDirection = -1;
+		lanesOnNextNode = pNextLink->numRightLanes;
+	}
+	float currentPathLinkForwardX = pVehicle->AutoPilot.m_nCurrentDirection * pCurLink->dirX;
+	float nextPathLinkForwardX = pVehicle->AutoPilot.m_nNextDirection * pNextLink->dirX;
+	if (lanesOnNextNode >= 0){
+		if ((CGeneral::GetRandomNumber() & 0x600) == 0){
+			/* 25% chance vehicle will try to switch lane */
+			CVector2D dist = pNextPathNode->pos - pCurPathNode->pos;
+			if (dist.MagnitudeSqr() >= SQR(14.0f)){
+				if (CGeneral::GetRandomTrueFalse())
+					pVehicle->AutoPilot.m_nNextLane += 1;
+				else
+					pVehicle->AutoPilot.m_nNextLane -= 1;
+			}
+		}
+		pVehicle->AutoPilot.m_nNextLane = min(lanesOnNextNode - 1, pVehicle->AutoPilot.m_nNextLane);
+		pVehicle->AutoPilot.m_nNextLane = max(0, pVehicle->AutoPilot.m_nNextLane);
+	}else{
+		pVehicle->AutoPilot.m_nNextLane = pVehicle->AutoPilot.m_nCurrentLane;
+	}
+	if (pVehicle->AutoPilot.m_bStayInFastLane)
+		pVehicle->AutoPilot.m_nNextLane = 0;
+	CVector positionOnCurrentLinkIncludingLane(
+		pCurLink->posX + GetOffsetOfLaneFromCenterOfRoad(pVehicle->AutoPilot.m_nCurrentLane, pCurLink), /* ...what about Y? */
+		pCurLink->posY - GetOffsetOfLaneFromCenterOfRoad(pVehicle->AutoPilot.m_nCurrentLane, pCurLink) * currentPathLinkForwardX,
+		0.0f);
+	CVector positionOnNextLinkIncludingLane(
+		pNextLink->posX + GetOffsetOfLaneFromCenterOfRoad(pVehicle->AutoPilot.m_nNextLane, pNextLink),
+		pNextLink->posY - GetOffsetOfLaneFromCenterOfRoad(pVehicle->AutoPilot.m_nNextLane, pNextLink) * nextPathLinkForwardX,
+		0.0f);
+	float directionCurrentLinkX = pCurLink->dirX * pVehicle->AutoPilot.m_nCurrentDirection;
+	float directionCurrentLinkY = pCurLink->dirY * pVehicle->AutoPilot.m_nCurrentDirection;
+	float directionNextLinkX = pNextLink->dirX * pVehicle->AutoPilot.m_nNextDirection;
+	float directionNextLinkY = pNextLink->dirY * pVehicle->AutoPilot.m_nNextDirection;
+	/* We want to make a path between two links that may not have the same forward directions a curve. */
+	pVehicle->AutoPilot.m_nTimeToSpendOnCurrentCurve = CCurves::CalcSpeedScaleFactor(
+		&positionOnCurrentLinkIncludingLane,
+		&positionOnNextLinkIncludingLane,
+		directionCurrentLinkX, directionCurrentLinkY,
+		directionNextLinkX, directionNextLinkY
+	) * (1000.0f / pVehicle->AutoPilot.m_fMaxTrafficSpeed);
+	if (pVehicle->AutoPilot.m_nTimeToSpendOnCurrentCurve < 10)
+		/* Oh hey there Obbe */
+		debug("fout\n");
+	pVehicle->AutoPilot.m_nTimeToSpendOnCurrentCurve = max(10, pVehicle->AutoPilot.m_nTimeToSpendOnCurrentCurve);
+}
+
+uint8 CCarCtrl::FindPathDirection(int32 prevNode, int32 curNode, int32 nextNode)
+{
+	CVector2D prevToCur = ThePaths.m_pathNodes[curNode].pos - ThePaths.m_pathNodes[prevNode].pos;
+	CVector2D curToNext = ThePaths.m_pathNodes[nextNode].pos - ThePaths.m_pathNodes[curNode].pos;
+	float distPrevToCur = prevToCur.Magnitude();
+	if (distPrevToCur == 0.0f)
+		return PATH_DIRECTION_NONE;
+	/* We are trying to determine angle between prevToCur and curToNext. */
+	/* To find it, we consider a to be an angle between y axis and prevToCur */
+	/* and b to be an angle between x axis and curToNext */
+	/* Then the angle we are looking for is (pi/2 + a + b). */
+	float sin_a = prevToCur.x / distPrevToCur;
+	float cos_a = prevToCur.y / distPrevToCur;
+	float distCurToNext = curToNext.Magnitude();
+	if (distCurToNext == 0.0f)
+		return PATH_DIRECTION_NONE;
+	float sin_b = curToNext.y / distCurToNext;
+	float cos_b = curToNext.x / distCurToNext;
+	/* sin(a) * sin(b) - cos(a) * cos(b) = -cos(a+b) = sin(pi/2+a+b) */
+	float sin_direction = sin_a * sin_b - cos_a * cos_b;
+	if (sin_direction > 0.77f) /* Roughly between -50 and -130 degrees */
+		return PATH_DIRECTION_LEFT;
+	if (sin_direction < -0.77f) /* Roughly between 50 and 130 degrees */
+		return PATH_DIRECTION_RIGHT;
+	return PATH_DIRECTION_STRAIGHT;
+}
+
+#ifdef FIX_PATHFIND_BUG
+//TODO: implement
+#else
+WRAPPER void CCarCtrl::PickNextNodeToChaseCar(CVehicle*, float, float, CVehicle*) { EAXJMP(0x41C480); }
+#endif
+
 bool
 CCarCtrl::MapCouldMoveInThisArea(float x, float y)
 {
@@ -1434,4 +1656,5 @@ InjectHook(0x418320, &CCarCtrl::RemoveDistantCars, PATCH_JUMP);
 InjectHook(0x418430, &CCarCtrl::PossiblyRemoveVehicle, PATCH_JUMP);
 InjectHook(0x418C10, &CCarCtrl::FindMaximumSpeedForThisCarInTraffic, PATCH_JUMP);
 InjectHook(0x41A590, &CCarCtrl::FindAngleToWeaveThroughTraffic, PATCH_JUMP);
+InjectHook(0x41BA50, &CCarCtrl::PickNextNodeAccordingStrategy, PATCH_JUMP);
 ENDPATCHES
diff --git a/src/control/CarCtrl.h b/src/control/CarCtrl.h
index 77982ba6..d5405137 100644
--- a/src/control/CarCtrl.h
+++ b/src/control/CarCtrl.h
@@ -11,6 +11,12 @@ enum{
 
 #define LANE_WIDTH 5.0f
 
+#ifdef FIX_BUGS
+#define FIX_PATHFIND_BUG
+#endif
+
+#undef FIX_PATHFIND_BUG
+
 class CCarCtrl
 {
 	enum eCarClass {
@@ -56,7 +62,7 @@ public:
 	static bool IsThisVehicleInteresting(CVehicle*);
 	static int32 CountCarsOfType(int32 mi);
 	static void SlowCarOnRailsDownForTrafficAndLights(CVehicle*);
-	static void PickNextNodeAccordingStrategy(CVehicle*);
+	static bool PickNextNodeAccordingStrategy(CVehicle*);
 	static void DragCarToPoint(CVehicle*, CVector*);
 	static float FindMaximumSpeedForThisCarInTraffic(CVehicle*);
 	static void SlowCarDownForCarsSectorList(CPtrList&, CVehicle*, float, float, float, float, float*, float);
@@ -71,6 +77,14 @@ public:
 	static void WeaveForPed(CEntity*, CVehicle*, float*, float*);
 	static void WeaveThroughObjectsSectorList(CPtrList&, CVehicle*, float, float, float, float, float*, float*);
 	static void WeaveForObject(CEntity*, CVehicle*, float*, float*);
+#ifdef FIX_PATHFIND_BUG
+	static void PickNextNodeToChaseCar(CVehicle*, float, float, float, CVehicle*);
+#else
+	static void PickNextNodeToChaseCar(CVehicle*, float, float, CVehicle*);
+#endif
+	static bool PickNextNodeToFollowPath(CVehicle*);
+	static void PickNextNodeRandomly(CVehicle*);
+	static uint8 FindPathDirection(int32, int32, int32);
 
 	static float GetOffsetOfLaneFromCenterOfRoad(int8 lane, CCarPathLink* pLink)
 	{
diff --git a/src/control/ScriptCommands.h b/src/control/ScriptCommands.h
index fcc0a23f..539a0bd2 100644
--- a/src/control/ScriptCommands.h
+++ b/src/control/ScriptCommands.h
@@ -1127,7 +1127,7 @@ enum {
 	COMMAND_GET_DEBUG_CAMERA_POINT_AT,
 	COMMAND_ATTACH_CHAR_TO_CAR,
 	COMMAND_DETACH_CHAR_FROM_CAR,
-	COMMAND_SET_CAR_CHANGE_LANE,
+	COMMAND_SET_CAR_STAY_IN_FAST_LANE,
 	COMMAND_CLEAR_CHAR_LAST_WEAPON_DAMAGE,
 	COMMAND_CLEAR_CAR_LAST_WEAPON_DAMAGE,
 	COMMAND_GET_RANDOM_COP_IN_AREA,