Apply clang-tidy fixes performance-unnecessary-value-param

The fixes that added std::move (C++11 only) were manually reverted
again. This sprinkles a ton of const refs all over the place, obviating
the need to copy-construct Position all the time.

src/Battlescape/AIModule.cpp

@@ -1506,7 +1506,7 @@ bool AIModule::findFirePoint()
  * @param grenade Is the explosion coming from a grenade?
  * @return True if it is worthwhile creating an explosion in the target position.
  */
-bool AIModule::explosiveEfficacy(Position targetPos, BattleUnit *attackingUnit, int radius, int diff, bool grenade) const
+bool AIModule::explosiveEfficacy(const Position& targetPos, BattleUnit *attackingUnit, int radius, int diff, bool grenade) const
 {
 	// i hate the player and i want him dead, but i don't want to piss him off.
 	Mod *mod = _save->getBattleState()->getGame()->getMod();

src/Battlescape/AIModule.h

@@ -95,7 +95,7 @@ class AIModule
 	/// Selects a suitable position from which to attack.
 	bool findFirePoint();
 	/// Decides if we should throw a grenade/launch a missile to this position.
-	bool explosiveEfficacy(Position targetPos, BattleUnit *attackingUnit, int radius, int diff, bool grenade = false) const;
+	bool explosiveEfficacy(const Position& targetPos, BattleUnit *attackingUnit, int radius, int diff, bool grenade = false) const;
 	bool getNodeOfBestEfficacy(BattleAction *action);
 	/// Attempts to take a melee attack/charge an enemy we can see.
 	void meleeAction();

src/Battlescape/BattlescapeGame.cpp

@@ -1427,7 +1427,7 @@ bool BattlescapeGame::isBusy() const
  * Activates primary action (left click).
  * @param pos Position on the map.
  */
-void BattlescapeGame::primaryAction(Position pos)
+void BattlescapeGame::primaryAction(const Position& pos)
 {
 	bool bPreviewed = Options::battleNewPreviewPath != PATH_NONE;
 
@@ -1572,7 +1572,7 @@ void BattlescapeGame::primaryAction(Position pos)
  * Activates secondary action (right click).
  * @param pos Position on the map.
  */
-void BattlescapeGame::secondaryAction(Position pos)
+void BattlescapeGame::secondaryAction(const Position& pos)
 {
 	//  -= turn to or open door =-
 	_currentAction.target = pos;
@@ -1671,7 +1671,7 @@ void BattlescapeGame::setTUReserved(BattleActionType tur)
  * @param newItem Bool whether this is a new item.
  * @param removeItem Bool whether to remove the item from the owner.
  */
-void BattlescapeGame::dropItem(Position position, BattleItem *item, bool newItem, bool removeItem)
+void BattlescapeGame::dropItem(const Position& position, BattleItem *item, bool newItem, bool removeItem)
 {
 	const Position& p = position;
 

src/Battlescape/BattlescapeGame.h

@@ -123,7 +123,7 @@ class BattlescapeGame
 	/// Handles unit AI.
 	void handleAI(BattleUnit *unit);
 	/// Drops an item and affects it with gravity.
-	void dropItem(Position position, BattleItem *item, bool newItem = false, bool removeItem = false);
+	void dropItem(const Position& position, BattleItem *item, bool newItem = false, bool removeItem = false);
 	/// Converts a unit into a unit of another type.
 	BattleUnit *convertUnit(BattleUnit *unit);
 	/// Handles kneeling action.
@@ -137,9 +137,9 @@ class BattlescapeGame
 	/// Determines whether there is an action currently going on.
 	bool isBusy() const;
 	/// Activates primary action (left click).
-	void primaryAction(Position pos);
+	void primaryAction(const Position& pos);
 	/// Activates secondary action (right click).
-	void secondaryAction(Position pos);
+	void secondaryAction(const Position& pos);
 	/// Handler for the blaster launcher button.
 	void launchAction();
 	/// Handler for the psi button.

src/Battlescape/Camera.cpp

@@ -403,7 +403,7 @@ void Camera::setViewLevel(int viewlevel)
  * @param mapPos Position to center on.
  * @param redraw Redraw map or not.
  */
-void Camera::centerOnPosition(Position mapPos, bool redraw)
+void Camera::centerOnPosition(const Position& mapPos, bool redraw)
 {
 	Position screenPos;
 	_center = mapPos;
@@ -458,7 +458,7 @@ void Camera::convertScreenToMap(int screenX, int screenY, int *mapX, int *mapY)
  * @param mapPos X,Y,Z coordinates on the map.
  * @param screenPos Screen position.
  */
-void Camera::convertMapToScreen(Position mapPos, Position *screenPos) const
+void Camera::convertMapToScreen(const Position& mapPos, Position *screenPos) const
 {
 	screenPos->z = 0; // not used
 	screenPos->x = mapPos.x * (_spriteWidth / 2) - mapPos.y * (_spriteWidth / 2);
@@ -470,7 +470,7 @@ void Camera::convertMapToScreen(Position mapPos, Position *screenPos) const
  * @param voxelPos X,Y,Z coordinates of the voxel.
  * @param screenPos Screen position.
  */
-void Camera::convertVoxelToScreen(Position voxelPos, Position *screenPos) const
+void Camera::convertVoxelToScreen(const Position& voxelPos, Position *screenPos) const
 {
 	Position mapPosition = Position(voxelPos.x / 16, voxelPos.y / 16, voxelPos.z / 24);
 	convertMapToScreen(mapPosition, screenPos);
@@ -555,7 +555,7 @@ bool Camera::getShowAllLayers() const
  * @param boundary True if it's for caching calculation
  * @return True if the map coordinates are on screen.
  */
-bool Camera::isOnScreen(Position mapPos, const bool unitWalking, const int unitSize, const bool boundary) const
+bool Camera::isOnScreen(const Position& mapPos, const bool unitWalking, const int unitSize, const bool boundary) const
 {
 	Position screenPos;
 	convertMapToScreen(mapPos, &screenPos);

src/Battlescape/Camera.h

@@ -77,13 +77,13 @@ class Camera
 	/// Sets the view level.
 	void setViewLevel(int viewlevel);
 	/// Converts map coordinates to screen coordinates.
-	void convertMapToScreen(Position mapPos, Position *screenPos) const;
+	void convertMapToScreen(const Position& mapPos, Position *screenPos) const;
 	/// Converts voxel coordinates to screen coordinates.
-	void convertVoxelToScreen(Position voxelPos, Position *screenPos) const;
+	void convertVoxelToScreen(const Position& voxelPos, Position *screenPos) const;
 	/// Converts screen coordinates to map coordinates.
 	void convertScreenToMap(int screenX, int screenY, int *mapX, int *mapY) const;
 	/// Center map on a position.
-	void centerOnPosition(Position pos, bool redraw = true);
+	void centerOnPosition(const Position& pos, bool redraw = true);
 	/// Gets map's center position.
 	Position getCenterPosition();
 	/// Gets the map displayed level.
@@ -101,7 +101,7 @@ class Camera
 	/// Checks if the camera is showing all map layers.
 	bool getShowAllLayers() const;
 	/// Checks if map coordinates X,Y,Z are on screen.
-	bool isOnScreen(Position mapPos, const bool unitWalking, const int unitSize, const bool boundary) const;
+	bool isOnScreen(const Position& mapPos, const bool unitWalking, const int unitSize, const bool boundary) const;
 	/// Resize the viewable area.
 	void resize();
 	/// stop mouse scrolling.

src/Battlescape/Explosion.cpp

@@ -31,7 +31,7 @@ const int Explosion::BULLET_FRAMES = 10;
  * @param big Flag to indicate it is a bullet hit (false), or a real explosion (true).
  * @param hit True for melee and psi attacks.
  */
-Explosion::Explosion(Position position, int startFrame, int frameDelay, bool big, bool hit) : _position(position), _currentFrame(startFrame), _startFrame(startFrame), _frameDelay(frameDelay), _big(big), _hit(hit)
+Explosion::Explosion(const Position& position, int startFrame, int frameDelay, bool big, bool hit) : _position(position), _currentFrame(startFrame), _startFrame(startFrame), _frameDelay(frameDelay), _big(big), _hit(hit)
 {
 
 }

src/Battlescape/Explosion.h

@@ -37,7 +37,7 @@ class Explosion
 	static const int EXPLODE_FRAMES;
 	static const int BULLET_FRAMES;
 	/// Creates a new Explosion.
-	Explosion(Position _position, int startFrame, int frameDelay = 0, bool big = false, bool hit = false);
+	Explosion(const Position& _position, int startFrame, int frameDelay = 0, bool big = false, bool hit = false);
 	/// Cleans up the Explosion.
 	~Explosion();
 	/// Moves the Explosion on one frame.

src/Battlescape/ExplosionBState.cpp

@@ -45,7 +45,7 @@ namespace OpenXcom
  * @param tile Tile the explosion is on.
  * @param lowerWeapon Whether the unit causing this explosion should now lower their weapon.
  */
-ExplosionBState::ExplosionBState(BattlescapeGame *parent, Position center, BattleItem *item, BattleUnit *unit, Tile *tile, bool lowerWeapon, bool cosmetic) : BattleState(parent), _unit(unit), _center(center), _item(item), _tile(tile), _power(0), _areaOfEffect(false), _lowerWeapon(lowerWeapon), _cosmetic(cosmetic)
+ExplosionBState::ExplosionBState(BattlescapeGame *parent, const Position& center, BattleItem *item, BattleUnit *unit, Tile *tile, bool lowerWeapon, bool cosmetic) : BattleState(parent), _unit(unit), _center(center), _item(item), _tile(tile), _power(0), _areaOfEffect(false), _lowerWeapon(lowerWeapon), _cosmetic(cosmetic)
 {
 
 }

src/Battlescape/ExplosionBState.h

@@ -45,7 +45,7 @@ class ExplosionBState : public BattleState
 	void explode();
 public:
 	/// Creates a new ExplosionBState class.
-	ExplosionBState(BattlescapeGame *parent, Position center, BattleItem *item, BattleUnit *unit, Tile *tile = 0, bool lowerWeapon = false, bool cosmetic = false);
+	ExplosionBState(BattlescapeGame *parent, const Position& center, BattleItem *item, BattleUnit *unit, Tile *tile = 0, bool lowerWeapon = false, bool cosmetic = false);
 	/// Cleans up the ExplosionBState.
 	~ExplosionBState();
 	/// Initializes the state.

src/Battlescape/Map.cpp

@@ -250,7 +250,7 @@ void Map::setPalette(SDL_Color *colors, int firstcolor, int ncolors)
 /**
  * Check two positions if have same XY cords
  */
-static bool positionHaveSameXY(Position a, Position b)
+static bool positionHaveSameXY(const Position& a, const Position& b)
 {
 	return a.x == b.x && a.y == b.y;
 }
@@ -265,7 +265,7 @@ static bool positionHaveSameXY(Position a, Position b)
  * @param obstacleShade unitShade override for no LOF obstacle indicator
  * @param topLayer
  */
-void Map::drawUnit(Surface *surface, Tile *unitTile, Tile *currTile, Position currTileScreenPosition, int shade, int obstacleShade, bool topLayer)
+void Map::drawUnit(Surface *surface, Tile *unitTile, Tile *currTile, const Position& currTileScreenPosition, int shade, int obstacleShade, bool topLayer)
 {
 	const int tileFoorWidth = 32;
 	const int tileFoorHeight = 16;

src/Battlescape/Map.h

@@ -69,7 +69,7 @@ class Map : public InteractiveSurface
 	Text *_txtAccuracy;
 	SurfaceSet *_projectileSet;
 
-	void drawUnit(Surface *surface, Tile *unitTile, Tile *currTile, Position tileScreenPosition, int shade, int obstacleShade, bool topLayer);
+	void drawUnit(Surface *surface, Tile *unitTile, Tile *currTile, const Position& tileScreenPosition, int shade, int obstacleShade, bool topLayer);
 	void drawTerrain(Surface *surface);
 	int getTerrainLevel(const Position& pos, int size) const;
 	int _iconHeight, _iconWidth, _messageColor;

src/Battlescape/Pathfinding.cpp

@@ -65,7 +65,7 @@ Pathfinding::~Pathfinding()
  * @param pos Position.
  * @return Pointer to node.
  */
-PathfindingNode *Pathfinding::getNode(Position pos)
+PathfindingNode *Pathfinding::getNode(const Position& pos)
 {
 	return &_nodes[_save->getTileIndex(pos)];
 }
@@ -189,7 +189,7 @@ void Pathfinding::calculate(BattleUnit *unit, Position endPosition, BattleUnit *
  * @param maxTUCost Maximum time units the path can cost.
  * @return True if a path exists, false otherwise.
  */
-bool Pathfinding::aStarPath(Position startPosition, Position endPosition, BattleUnit *target, bool sneak, int maxTUCost)
+bool Pathfinding::aStarPath(const Position& startPosition, const Position& endPosition, BattleUnit *target, bool sneak, int maxTUCost)
 {
 	// reset every node, so we have to check them all
 	for (std::vector<PathfindingNode>::iterator it = _nodes.begin(); it != _nodes.end(); ++it)
@@ -255,7 +255,7 @@ bool Pathfinding::aStarPath(Position startPosition, Position endPosition, Battle
  * @param missile Is this a guided missile?
  * @return TU cost or 255 if movement is impossible.
  */
-int Pathfinding::getTUCost(Position startPosition, int direction, Position *endPosition, BattleUnit *unit, BattleUnit *target, bool missile)
+int Pathfinding::getTUCost(const Position& startPosition, int direction, Position *endPosition, BattleUnit *unit, BattleUnit *target, bool missile)
 {
 	_unit = unit;
 	directionToVector(direction, endPosition);
@@ -527,7 +527,7 @@ void Pathfinding::directionToVector(int direction, Position *vector)
  * @param vector Pointer to a position (which acts as a vector).
  * @param dir Resulting direction.
  */
-void Pathfinding::vectorToDirection(Position vector, int &dir)
+void Pathfinding::vectorToDirection(const Position& vector, int &dir)
 {
 	dir = -1;
 	int x[8] = {0, 1, 1, 1, 0, -1, -1, -1};
@@ -798,7 +798,7 @@ bool Pathfinding::canFallDown(Tile *here, int size) const
  * @param endPosition The position we wanna reach.
  * @return True if the unit is going up a stairs.
  */
-bool Pathfinding::isOnStairs(Position startPosition, Position endPosition) const
+bool Pathfinding::isOnStairs(const Position& startPosition, const Position& endPosition) const
 {
 	//condition 1 : endposition has to the south a terrainlevel -16 object (upper part of the stairs)
 	if (_save->getTile(endPosition + Position(0, 1, 0)) && _save->getTile(endPosition + Position(0, 1, 0))->getTerrainLevel() == -16)
@@ -1024,7 +1024,7 @@ bool Pathfinding::removePreview()
  * @param maxTUCost Maximum time units the path can cost.
  * @return True if a path exists, false otherwise.
  */
-bool Pathfinding::bresenhamPath(Position origin, Position target, BattleUnit *targetUnit, bool sneak, int maxTUCost)
+bool Pathfinding::bresenhamPath(const Position& origin, const Position& target, BattleUnit *targetUnit, bool sneak, int maxTUCost)
 {
 	int xd[8] = {0, 1, 1, 1, 0, -1, -1, -1};
 	int yd[8] = {-1, -1, 0, 1, 1, 1, 0, -1};

src/Battlescape/Pathfinding.h

@@ -45,21 +45,21 @@ class Pathfinding
 	bool _modifierUsed;
 	MovementType _movementType;
 	/// Gets the node at certain position.
-	PathfindingNode *getNode(Position pos);
+	PathfindingNode *getNode(const Position& pos);
 	/// Determines whether a tile blocks a certain movementType.
 	bool isBlocked(Tile *tile, const int part, BattleUnit *missileTarget, int bigWallExclusion = -1) const;
 	/// Tries to find a straight line path between two positions.
-	bool bresenhamPath(Position origin, Position target, BattleUnit *missileTarget, bool sneak = false, int maxTUCost = 1000);
+	bool bresenhamPath(const Position& origin, const Position& target, BattleUnit *missileTarget, bool sneak = false, int maxTUCost = 1000);
 	/// Tries to find a path between two positions.
-	bool aStarPath(Position origin, Position target, BattleUnit *missileTarget, bool sneak = false, int maxTUCost = 1000);
+	bool aStarPath(const Position& origin, const Position& target, BattleUnit *missileTarget, bool sneak = false, int maxTUCost = 1000);
 	/// Determines whether a unit can fall down from this tile.
 	bool canFallDown(Tile *destinationTile) const;
 	/// Determines whether a unit can fall down from this tile.
 	bool canFallDown(Tile *destinationTile, int size) const;
 	std::vector<int> _path;
 public:
 	/// Determines whether the unit is going up a stairs.
-	bool isOnStairs(Position startPosition, Position endPosition) const;
+	bool isOnStairs(const Position& startPosition, const Position& endPosition) const;
 	/// Determines whether or not movement between starttile and endtile is possible in the direction.
 	bool isBlocked(Tile *startTile, Tile *endTile, const int direction, BattleUnit *missileTarget);
 	static const int DIR_UP = 8;
@@ -78,13 +78,13 @@ class Pathfinding
 	/// Converts direction to a vector.
 	static void directionToVector(int direction, Position *vector);
 	/// Converts a vector to a direction.
-	static void vectorToDirection(Position vector, int &dir);
+	static void vectorToDirection(const Position& vector, int &dir);
 	/// Checks whether a path is ready and gives the first direction.
 	int getStartDirection() const;
 	/// Dequeues a direction.
 	int dequeuePath();
 	/// Gets the TU cost to move from 1 tile to the other.
-	int getTUCost(Position startPosition, int direction, Position *endPosition, BattleUnit *unit, BattleUnit *target, bool missile);
+	int getTUCost(const Position& startPosition, int direction, Position *endPosition, BattleUnit *unit, BattleUnit *target, bool missile);
 	/// Aborts the current path.
 	void abortPath();
 	/// Gets the strafe move setting.

src/Battlescape/PathfindingNode.cpp

@@ -26,7 +26,7 @@ namespace OpenXcom
  * Sets up a PathfindingNode.
  * @param pos Position.
  */
-PathfindingNode::PathfindingNode(Position pos) : _pos(pos), _checked(0), _tuCost(0), _prevNode(0), _prevDir(0), _tuGuess(0), _openentry(0)
+PathfindingNode::PathfindingNode(const Position& pos) : _pos(pos), _checked(0), _tuCost(0), _prevNode(0), _prevDir(0), _tuGuess(0), _openentry(0)
 {
 
 }
@@ -105,7 +105,7 @@ int PathfindingNode::getPrevDir() const
  * @param prevDir The direction FROM the previous node.
  * @param target The target position (used to update our guess cost).
  */
-void PathfindingNode::connect(int tuCost, PathfindingNode* prevNode, int prevDir, Position target)
+void PathfindingNode::connect(int tuCost, PathfindingNode* prevNode, int prevDir, const Position& target)
 {
 	_tuCost = tuCost;
 	_prevNode = prevNode;

src/Battlescape/PathfindingNode.h

@@ -43,7 +43,7 @@ class PathfindingNode
 	friend class PathfindingOpenSet;
 public:
 	/// Creates a new PathfindingNode class.
-	PathfindingNode(Position pos);
+	PathfindingNode(const Position& pos);
 	/// Cleans up the PathfindingNode.
 	~PathfindingNode();
 	/// Gets the node position.
@@ -70,7 +70,7 @@ class PathfindingNode
 	#endif
 
 	/// Connects to previous node along the path.
-	void connect(int tuCost, PathfindingNode* prevNode, int prevDir, Position target);
+	void connect(int tuCost, PathfindingNode* prevNode, int prevDir, const Position& target);
 	/// Connects to previous node along a visit.
 	void connect(int tuCost, PathfindingNode* prevNode, int prevDir);
 };

src/Battlescape/Projectile.cpp

@@ -46,7 +46,7 @@ namespace OpenXcom
  * @param targetVoxel Position the projectile is targeting.
  * @param ammo the ammo that produced this projectile, where applicable.
  */
-Projectile::Projectile(Mod *mod, SavedBattleGame *save, BattleAction action, Position origin, Position targetVoxel, BattleItem *ammo) : _mod(mod), _save(save), _action(action), _origin(origin), _targetVoxel(targetVoxel), _position(0), _bulletSprite(-1), _reversed(false), _vaporColor(-1), _vaporDensity(-1), _vaporProbability(5)
+Projectile::Projectile(Mod *mod, SavedBattleGame *save, BattleAction action, const Position& origin, const Position& targetVoxel, BattleItem *ammo) : _mod(mod), _save(save), _action(action), _origin(origin), _targetVoxel(targetVoxel), _position(0), _bulletSprite(-1), _reversed(false), _vaporColor(-1), _vaporDensity(-1), _vaporProbability(5)
 {
 	// this is the number of pixels the sprite will move between frames
 	_speed = Options::battleFireSpeed;
@@ -331,7 +331,7 @@ int Projectile::calculateThrow(double accuracy)
  * @param keepRange Whether range affects accuracy.
  * @param extendLine should this line get extended to maximum distance?
  */
-void Projectile::applyAccuracy(Position origin, Position *target, double accuracy, bool keepRange, bool extendLine)
+void Projectile::applyAccuracy(const Position& origin, Position *target, double accuracy, bool keepRange, bool extendLine)
 {
 	int xdiff = origin.x - target->x;
 	int ydiff = origin.y - target->y;

src/Battlescape/Projectile.h

@@ -57,10 +57,10 @@ class Projectile
 	int _bulletSprite;
 	bool _reversed;
 	int _vaporColor, _vaporDensity, _vaporProbability;
-	void applyAccuracy(Position origin, Position *target, double accuracy, bool keepRange, bool extendLine);
+	void applyAccuracy(const Position& origin, Position *target, double accuracy, bool keepRange, bool extendLine);
 public:
 	/// Creates a new Projectile.
-	Projectile(Mod *mod, SavedBattleGame *save, BattleAction action, Position origin, Position target, BattleItem *ammo);
+	Projectile(Mod *mod, SavedBattleGame *save, BattleAction action, const Position& origin, const Position& target, BattleItem *ammo);
 	/// Cleans up the Projectile.
 	~Projectile();
 	/// Calculates the trajectory for a straight path.