Modernize source code: last part (#6285)

* Modernize source code: last par

* Use empty when needed
* Use emplace_back instead of push_back when needed
* For range-based loops
* Initializers fixes
* constructors, destructors default
* c++ C stl includes

72 files changed, 445 insertions, 583 deletions

diff --git a/src/camera.h b/src/camera.h
index 0b5c7441f..01dc54104 100644
--- a/src/camera.h
+++ b/src/camera.h
@@ -35,7 +35,7 @@ struct Nametag {
 	Nametag(scene::ISceneNode *a_parent_node,
 			const std::string &a_nametag_text,
 			const video::SColor &a_nametag_color,
-			const v3f a_nametag_pos):
+			const v3f &a_nametag_pos):
 		parent_node(a_parent_node),
 		nametag_text(a_nametag_text),
 		nametag_color(a_nametag_color),
diff --git a/src/chat.cpp b/src/chat.cpp
index 3785b7797..35c6329c3 100644
--- a/src/chat.cpp
+++ b/src/chat.cpp
@@ -365,8 +365,8 @@ s32 ChatBuffer::getBottomScrollPos() const
 	s32 rows = (s32) m_rows;
 	if (rows == 0)
 		return 0;
-	else
-		return formatted_count - rows;
+
+	return formatted_count - rows;
 }
 
 
diff --git a/src/database-dummy.h b/src/database-dummy.h
index d65890411..2d87d58f6 100644
--- a/src/database-dummy.h
+++ b/src/database-dummy.h
@@ -35,7 +35,7 @@ public:
 	void savePlayer(RemotePlayer *player) {}
 	bool loadPlayer(RemotePlayer *player, PlayerSAO *sao) { return true; }
 	bool removePlayer(const std::string &name) { return true; }
-	void listPlayers(std::vector<std::string> &) {}
+	void listPlayers(std::vector<std::string> &res) {}
 
 	void beginSave() {}
 	void endSave() {}
diff --git a/src/emerge.h b/src/emerge.h
index b2099a440..005760150 100644
--- a/src/emerge.h
+++ b/src/emerge.h
@@ -29,10 +29,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define BLOCK_EMERGE_ALLOW_GEN   (1 << 0)
 #define BLOCK_EMERGE_FORCE_QUEUE (1 << 1)
 
-#define EMERGE_DBG_OUT(x) do {                         \
+#define EMERGE_DBG_OUT(x) {                            \
 	if (enable_mapgen_debug_info)                      \
 		infostream << "EmergeThread: " x << std::endl; \
-} while (0)
+}
 
 class EmergeThread;
 class INodeDefManager;
diff --git a/src/event.h b/src/event.h
index c53c59d74..488152855 100644
--- a/src/event.h
+++ b/src/event.h
@@ -22,7 +22,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 class MtEvent
 {
 public:
-	virtual ~MtEvent() {};
+	virtual ~MtEvent() = default;
 	//virtual MtEvent* clone(){ return new IEvent; }
 	virtual const char* getType() const = 0;
 
@@ -49,7 +49,7 @@ public:
 class MtEventReceiver
 {
 public:
-	virtual ~MtEventReceiver(){};
+	virtual ~MtEventReceiver() = default;
 	virtual void onEvent(MtEvent *e) = 0;
 };
 
@@ -58,7 +58,7 @@ typedef void (*event_receive_func)(MtEvent *e, void *data);
 class MtEventManager
 {
 public:
-	virtual ~MtEventManager(){};
+	virtual ~MtEventManager() = default;
 	virtual void put(MtEvent *e) = 0;
 	virtual void reg(const char *type, event_receive_func f, void *data) = 0;
 	// If data==NULL, every occurence of f is deregistered.
diff --git a/src/event_manager.h b/src/event_manager.h
index 54cd728bd..f64d05869 100644
--- a/src/event_manager.h
+++ b/src/event_manager.h
@@ -43,17 +43,15 @@ class EventManager: public MtEventManager
 	std::map<std::string, Dest> m_dest;
 
 public:
-	~EventManager()
-	{
-	}
+	~EventManager() = default;
+
 	void put(MtEvent *e)
 	{
 		std::map<std::string, Dest>::iterator i = m_dest.find(e->getType());
 		if(i != m_dest.end()){
 			std::list<FuncSpec> &funcs = i->second.funcs;
-			for(std::list<FuncSpec>::iterator i = funcs.begin();
-					i != funcs.end(); ++i){
-				(*(i->f))(e, i->d);
+			for (FuncSpec &func : funcs) {
+				(*(func.f))(e, func.d);
 			}
 		}
 		delete e;
@@ -62,11 +60,11 @@ public:
 	{
 		std::map<std::string, Dest>::iterator i = m_dest.find(type);
 		if(i != m_dest.end()){
-			i->second.funcs.push_back(FuncSpec(f, data));
+			i->second.funcs.emplace_back(f, data);
 		} else{
 			std::list<FuncSpec> funcs;
 			Dest dest;
-			dest.funcs.push_back(FuncSpec(f, data));
+			dest.funcs.emplace_back(f, data);
 			m_dest[type] = dest;
 		}
 	}
@@ -86,9 +84,8 @@ public:
 				}
 			}
 		} else{
-			for(std::map<std::string, Dest>::iterator
-					i = m_dest.begin(); i != m_dest.end(); ++i){
-				std::list<FuncSpec> &funcs = i->second.funcs;
+			for (auto &dest : m_dest) {
+				std::list<FuncSpec> &funcs = dest.second.funcs;
 				std::list<FuncSpec>::iterator j = funcs.begin();
 				while(j != funcs.end()){
 					bool remove = (j->f == f && (!data || j->d == data));
diff --git a/src/exceptions.h b/src/exceptions.h
index a8a7db74c..c54307653 100644
--- a/src/exceptions.h
+++ b/src/exceptions.h
@@ -27,7 +27,8 @@ class BaseException : public std::exception
 {
 public:
 	BaseException(const std::string &s) throw(): m_s(s) {}
-	~BaseException() throw() {}
+	~BaseException() throw() = default;
+
 	virtual const char * what() const throw()
 	{
 		return m_s.c_str();
diff --git a/src/game.cpp b/src/game.cpp
index 233c26525..fad902d03 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -69,8 +69,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 	#include "sound_openal.h"
 #endif
 
-extern Settings *g_settings;
-extern Profiler *g_profiler;
 
 /*
 	Text input system
@@ -248,7 +246,7 @@ void update_profiler_gui(gui::IGUIStaticText *guitext_profiler, FontEngine *fe,
 		setStaticText(guitext_profiler, text.c_str());
 		guitext_profiler->setVisible(true);
 
-		s32 w = fe->getTextWidth(text.c_str());
+		s32 w = fe->getTextWidth(text);
 
 		if (w < 400)
 			w = 400;
@@ -291,11 +289,9 @@ private:
 	};
 	std::deque<Piece> m_log;
 public:
-	u32 m_log_max_size;
+	u32 m_log_max_size = 200;
 
-	ProfilerGraph():
-		m_log_max_size(200)
-	{}
+	ProfilerGraph() = default;
 
 	void put(const Profiler::GraphValues &values)
 	{
@@ -314,14 +310,10 @@ public:
 		// to be the same for each call to prevent flickering
 		std::map<std::string, Meta> m_meta;
 
-		for (std::deque<Piece>::const_iterator k = m_log.begin();
-				k != m_log.end(); ++k) {
-			const Piece &piece = *k;
-
-			for (Profiler::GraphValues::const_iterator i = piece.values.begin();
-					i != piece.values.end(); ++i) {
-				const std::string &id = i->first;
-				const float &value = i->second;
+		for (const Piece &piece : m_log) {
+			for (const auto &i : piece.values) {
+				const std::string &id = i.first;
+				const float &value = i.second;
 				std::map<std::string, Meta>::iterator j = m_meta.find(id);
 
 				if (j == m_meta.end()) {
@@ -349,9 +341,8 @@ public:
 			sizeof(usable_colors) / sizeof(*usable_colors);
 		u32 next_color_i = 0;
 
-		for (std::map<std::string, Meta>::iterator i = m_meta.begin();
-				i != m_meta.end(); ++i) {
-			Meta &meta = i->second;
+		for (auto &i : m_meta) {
+			Meta &meta = i.second;
 			video::SColor color(255, 200, 200, 200);
 
 			if (next_color_i < usable_colors_count)
@@ -401,9 +392,7 @@ public:
 			float lastscaledvalue = 0.0;
 			bool lastscaledvalue_exists = false;
 
-			for (std::deque<Piece>::const_iterator j = m_log.begin();
-					j != m_log.end(); ++j) {
-				const Piece &piece = *j;
+			for (const Piece &piece : m_log) {
 				float value = 0;
 				bool value_exists = false;
 				Profiler::GraphValues::const_iterator k =
@@ -763,8 +752,8 @@ public:
 
 	void setSky(Sky *sky) {
 		m_sky = sky;
-		for (size_t i = 0; i < created_nosky.size(); ++i) {
-			created_nosky[i]->setSky(m_sky);
+		for (GameGlobalShaderConstantSetter *ggscs : created_nosky) {
+			ggscs->setSky(m_sky);
 		}
 		created_nosky.clear();
 	}
@@ -793,7 +782,7 @@ bool nodePlacementPrediction(Client &client, const ItemDefinition &playeritem_de
 	if (!is_valid_position)
 		return false;
 
-	if (prediction != "" && !nodedef->get(node).rightclickable) {
+	if (!prediction.empty() && !nodedef->get(node).rightclickable) {
 		verbosestream << "Node placement prediction for "
 			      << playeritem_def.name << " is "
 			      << prediction << std::endl;
@@ -978,7 +967,7 @@ static void updateChat(Client &client, f32 dtime, bool show_debug,
 	}
 
 	// Get new messages from client
-	std::wstring message = L"";
+	std::wstring message;
 	while (client.getChatMessage(message)) {
 		chat_backend.addUnparsedMessage(message);
 	}
@@ -1116,8 +1105,8 @@ void KeyCache::populate()
 	if (handler) {
 		// First clear all keys, then re-add the ones we listen for
 		handler->dontListenForKeys();
-		for (size_t i = 0; i < KeyType::INTERNAL_ENUM_COUNT; i++) {
-			handler->listenForKey(key[i]);
+		for (const KeyPress &k : key) {
+			handler->listenForKey(k);
 		}
 		handler->listenForKey(EscapeKey);
 		handler->listenForKey(CancelKey);
@@ -1384,7 +1373,7 @@ private:
 
 	GameOnDemandSoundFetcher soundfetcher; // useful when testing
 	ISoundManager *sound;
-	bool sound_is_dummy;
+	bool sound_is_dummy = false;
 	SoundMaker *soundmaker;
 
 	ChatBackend *chat_backend;
@@ -1464,9 +1453,9 @@ private:
 	f32  m_cache_cam_smoothing;
 	f32  m_cache_fog_start;
 
-	bool m_invert_mouse;
-	bool m_first_loop_after_window_activation;
-	bool m_camera_offset_changed;
+	bool m_invert_mouse = false;
+	bool m_first_loop_after_window_activation = false;
+	bool m_camera_offset_changed = false;
 
 #ifdef __ANDROID__
 	bool m_cache_hold_aux1;
@@ -1482,7 +1471,6 @@ Game::Game() :
 	itemdef_manager(NULL),
 	nodedef_manager(NULL),
 	sound(NULL),
-	sound_is_dummy(false),
 	soundmaker(NULL),
 	chat_backend(NULL),
 	current_formspec(NULL),
@@ -1496,10 +1484,7 @@ Game::Game() :
 	sky(NULL),
 	local_inventory(NULL),
 	hud(NULL),
-	mapper(NULL),
-	m_invert_mouse(false),
-	m_first_loop_after_window_activation(false),
-	m_camera_offset_changed(false)
+	mapper(NULL)
 {
 	g_settings->registerChangedCallback("doubletap_jump",
 		&settingChangedCallback, this);
@@ -1806,7 +1791,7 @@ bool Game::init(
 		return false;
 
 	// Create a server if not connecting to an existing one
-	if (*address == "") {
+	if (address->empty()) {
 		if (!createSingleplayerServer(map_dir, gamespec, port, address))
 			return false;
 	}
@@ -2168,7 +2153,7 @@ bool Game::connectToServer(const std::string &playername,
 
 			wait_time += dtime;
 			// Only time out if we aren't waiting for the server we started
-			if ((*address != "") && (wait_time > 10)) {
+			if ((!address->empty()) && (wait_time > 10)) {
 				bool sent_old_init = g_settings->getFlag("send_pre_v25_init");
 				// If no pre v25 init was sent, and no answer was received,
 				// but the low level connection could be established
@@ -3175,8 +3160,9 @@ void Game::processClientEvents(CameraOrientation *cam)
 			break;
 
 		case CE_SHOW_FORMSPEC:
-			if (*(event.show_formspec.formspec) == "") {
-				if (current_formspec && ( *(event.show_formspec.formname) == "" || *(event.show_formspec.formname) == cur_formname) ){
+			if (event.show_formspec.formspec->empty()) {
+				if (current_formspec && (event.show_formspec.formname->empty()
+						|| *(event.show_formspec.formname) == cur_formname)) {
 					current_formspec->quitMenu();
 				}
 			} else {
@@ -3713,7 +3699,7 @@ PointedThing Game::updatePointedThing(
 	}
 
 	// Update selection mesh light level and vertex colors
-	if (selectionboxes->size() > 0) {
+	if (!selectionboxes->empty()) {
 		v3f pf = hud->getSelectionPos();
 		v3s16 p = floatToInt(pf, BS);
 
@@ -3722,8 +3708,8 @@ PointedThing Game::updatePointedThing(
 		u16 node_light = getInteriorLight(n, -1, nodedef);
 		u16 light_level = node_light;
 
-		for (u8 i = 0; i < 6; i++) {
-			n = map.getNodeNoEx(p + g_6dirs[i]);
+		for (const v3s16 &dir : g_6dirs) {
+			n = map.getNodeNoEx(p + dir);
 			node_light = getInteriorLight(n, -1, nodedef);
 			if (node_light > light_level)
 				light_level = node_light;
@@ -3797,7 +3783,7 @@ void Game::handlePointingAtNode(const PointedThing &pointed,
 		runData.repeat_rightclick_timer = 0;
 		infostream << "Ground right-clicked" << std::endl;
 
-		if (meta && meta->getString("formspec") != "" && !random_input
+		if (meta && !meta->getString("formspec").empty() && !random_input
 				&& !isKeyDown(KeyType::SNEAK)) {
 			// Report right click to server
 			if (nodedef_manager->get(map.getNodeNoEx(nodepos)).rightclickable) {
@@ -3842,7 +3828,7 @@ void Game::handlePointingAtNode(const PointedThing &pointed,
 				soundmaker->m_player_rightpunch_sound =
 						SimpleSoundSpec();
 
-				if (playeritem_def.node_placement_prediction == "" ||
+				if (playeritem_def.node_placement_prediction.empty() ||
 						nodedef_manager->get(map.getNodeNoEx(nodepos)).rightclickable) {
 					client->interact(3, pointed); // Report to server
 				} else {
@@ -3862,7 +3848,7 @@ void Game::handlePointingAtObject(const PointedThing &pointed, const ItemStack &
 		utf8_to_wide(runData.selected_object->infoText()));
 
 	if (show_debug) {
-		if (infotext != L"") {
+		if (!infotext.empty()) {
 			infotext += L"\n";
 		}
 		infotext += unescape_enriched(utf8_to_wide(
@@ -3973,7 +3959,7 @@ void Game::handleDigging(const PointedThing &pointed, const v3s16 &nodepos,
 
 	if (sound_dig.exists() && params.diggable) {
 		if (sound_dig.name == "__group") {
-			if (params.main_group != "") {
+			if (!params.main_group.empty()) {
 				soundmaker->m_player_leftpunch_sound.gain = 0.5;
 				soundmaker->m_player_leftpunch_sound.name =
 						std::string("default_dig_") +
@@ -4649,7 +4635,7 @@ void Game::showPauseMenu()
 	static const std::string mode = strgettext("- Mode: ");
 	if (!simple_singleplayer_mode) {
 		Address serverAddress = client->getServerAddress();
-		if (address != "") {
+		if (!address.empty()) {
 			os << mode << strgettext("Remote server") << "\n"
 					<< strgettext("- Address: ") << address;
 		} else {
@@ -4659,7 +4645,7 @@ void Game::showPauseMenu()
 	} else {
 		os << mode << strgettext("Singleplayer") << "\n";
 	}
-	if (simple_singleplayer_mode || address == "") {
+	if (simple_singleplayer_mode || address.empty()) {
 		static const std::string on = strgettext("On");
 		static const std::string off = strgettext("Off");
 		const std::string &damage = g_settings->getBool("enable_damage") ? on : off;
@@ -4673,7 +4659,7 @@ void Game::showPauseMenu()
 					<< strgettext("- Public: ") << announced << "\n";
 			std::string server_name = g_settings->get("server_name");
 			str_formspec_escape(server_name);
-			if (announced == on && server_name != "")
+			if (announced == on && !server_name.empty())
 				os << strgettext("- Server Name: ") << server_name;
 
 		}
diff --git a/src/gettime.h b/src/gettime.h
index bae8b97c0..f20728dfd 100644
--- a/src/gettime.h
+++ b/src/gettime.h
@@ -20,7 +20,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #pragma once
 
 #include "irrlichttypes.h"
-#include <time.h>
+#include <ctime>
 #include <string>
 
 enum TimePrecision
diff --git a/src/itemdef.h b/src/itemdef.h
index 4c754f1da..bca922d3a 100644
--- a/src/itemdef.h
+++ b/src/itemdef.h
@@ -100,8 +100,9 @@ private:
 class IItemDefManager
 {
 public:
-	IItemDefManager(){}
-	virtual ~IItemDefManager(){}
+	IItemDefManager() = default;
+
+	virtual ~IItemDefManager() = default;
 
 	// Get item definition
 	virtual const ItemDefinition& get(const std::string &name) const=0;
@@ -133,8 +134,9 @@ public:
 class IWritableItemDefManager : public IItemDefManager
 {
 public:
-	IWritableItemDefManager(){}
-	virtual ~IWritableItemDefManager(){}
+	IWritableItemDefManager() = default;
+
+	virtual ~IWritableItemDefManager() = default;
 
 	// Get item definition
 	virtual const ItemDefinition& get(const std::string &name) const=0;
diff --git a/src/main.cpp b/src/main.cpp
index 52c8aff3c..c75c6a328 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -352,8 +352,8 @@ static void print_worldspecs(const std::vector<WorldSpec> &worldspecs,
 		std::string name = worldspec.name;
 		std::string path = worldspec.path;
 		if (name.find(' ') != std::string::npos)
-			name = std::string("'") + name + "'";
-		path = std::string("'") + path + "'";
+			name = std::string("'").append(name).append("'");
+		path = std::string("'").append(path).append("'");
 		name = padStringRight(name, 14);
 		os << "  " << name << " " << path << std::endl;
 	}
diff --git a/src/mainmenumanager.h b/src/mainmenumanager.h
index c9964a97e..ea9327813 100644
--- a/src/mainmenumanager.h
+++ b/src/mainmenumanager.h
@@ -48,9 +48,11 @@ class MainMenuManager : public IMenuManager
 public:
 	virtual void createdMenu(gui::IGUIElement *menu)
 	{
+#ifndef NDEBUG
 		for (gui::IGUIElement *i : m_stack) {
 			assert(i != menu);
 		}
+#endif
 
 		if(!m_stack.empty())
 			m_stack.back()->setVisible(false);
diff --git a/src/mapnode.cpp b/src/mapnode.cpp
index 8799eb380..9b6a39e1b 100644
--- a/src/mapnode.cpp
+++ b/src/mapnode.cpp
@@ -431,12 +431,11 @@ void transformNodeBox(const MapNode &n, const NodeBox &nodebox,
 			boxes_size += nodebox.connect_right.size();
 		boxes.reserve(boxes_size);
 
-#define BOXESPUSHBACK(c) do { \
+#define BOXESPUSHBACK(c) \
 		for (std::vector<aabb3f>::const_iterator \
 				it = (c).begin(); \
 				it != (c).end(); ++it) \
-			(boxes).push_back(*it); \
-		} while (0)
+			(boxes).push_back(*it);
 
 		BOXESPUSHBACK(nodebox.fixed);
 
diff --git a/src/network/connection.cpp b/src/network/connection.cpp
index a74e96784..77ce34bfd 100644
--- a/src/network/connection.cpp
+++ b/src/network/connection.cpp
@@ -1281,7 +1281,7 @@ bool ConnectionSendThread::packetsQueued()
 			continue;
 
 		for (Channel &channel : (dynamic_cast<UDPPeer *>(&peer))->channels) {
-			if (channel.queued_commands.size() > 0) {
+			if (!channel.queued_commands.empty()) {
 				return true;
 			}
 		}
diff --git a/src/network/connection.h b/src/network/connection.h
index c64272035..c0a39f313 100644
--- a/src/network/connection.h
+++ b/src/network/connection.h
@@ -604,7 +604,7 @@ public:
 class PeerHelper
 {
 public:
-	PeerHelper() = default;;
+	PeerHelper() = default;
 	PeerHelper(Peer* peer);
 	~PeerHelper();
 
diff --git a/src/script/common/c_content.cpp b/src/script/common/c_content.cpp
index 8d94235ce..ddcdd803d 100644
--- a/src/script/common/c_content.cpp
+++ b/src/script/common/c_content.cpp
@@ -91,7 +91,7 @@ void read_item_definition(lua_State* L, int index,
 	// If name is "" (hand), ensure there are ToolCapabilities
 	// because it will be looked up there whenever any other item has
 	// no ToolCapabilities
-	if(def.name == "" && def.tool_capabilities == NULL){
+	if (def.name.empty() && def.tool_capabilities == NULL){
 		def.tool_capabilities = new ToolCapabilities();
 	}
 
@@ -212,9 +212,9 @@ void read_object_properties(lua_State *L, int index,
 		while(lua_next(L, table) != 0){
 			// key at index -2 and value at index -1
 			if(lua_isstring(L, -1))
-				prop->textures.push_back(lua_tostring(L, -1));
+				prop->textures.emplace_back(lua_tostring(L, -1));
 			else
-				prop->textures.push_back("");
+				prop->textures.emplace_back("");
 			// removes value, keeps key for next iteration
 			lua_pop(L, 1);
 		}
@@ -303,18 +303,16 @@ void push_object_properties(lua_State *L, ObjectProperties *prop)
 
 	lua_newtable(L);
 	u16 i = 1;
-	for (std::vector<std::string>::iterator it = prop->textures.begin();
-			it != prop->textures.end(); ++it) {
-		lua_pushlstring(L, it->c_str(), it->size());
+	for (const std::string &texture : prop->textures) {
+		lua_pushlstring(L, texture.c_str(), texture.size());
 		lua_rawseti(L, -2, i);
 	}
 	lua_setfield(L, -2, "textures");
 
 	lua_newtable(L);
 	i = 1;
-	for (std::vector<video::SColor>::iterator it = prop->colors.begin();
-			it != prop->colors.end(); ++it) {
-		push_ARGB8(L, *it);
+	for (const video::SColor &color : prop->colors) {
+		push_ARGB8(L, color);
 		lua_rawseti(L, -2, i);
 	}
 	lua_setfield(L, -2, "colors");
@@ -564,7 +562,7 @@ ContentFeatures read_content_features(lua_State *L, int index)
 	f.param_type_2 = (ContentParamType2)getenumfield(L, index, "paramtype2",
 			ScriptApiNode::es_ContentParamType2, CPT2_NONE);
 
-	if (f.palette_name != "" &&
+	if (!f.palette_name.empty() &&
 			!(f.param_type_2 == CPT2_COLOR ||
 			f.param_type_2 == CPT2_COLORED_FACEDIR ||
 			f.param_type_2 == CPT2_COLORED_WALLMOUNTED))
@@ -646,7 +644,7 @@ ContentFeatures read_content_features(lua_State *L, int index)
 		lua_pushnil(L);
 		while (lua_next(L, table) != 0) {
 			// Value at -1
-			f.connects_to.push_back(lua_tostring(L, -1));
+			f.connects_to.emplace_back(lua_tostring(L, -1));
 			lua_pop(L, 1);
 		}
 	}
@@ -771,9 +769,8 @@ void push_content_features(lua_State *L, const ContentFeatures &c)
 
 	lua_newtable(L);
 	u16 i = 1;
-	for (std::vector<std::string>::const_iterator it = c.connects_to.begin();
-			it != c.connects_to.end(); ++it) {
-		lua_pushlstring(L, it->c_str(), it->size());
+	for (const std::string &it : c.connects_to) {
+		lua_pushlstring(L, it.c_str(), it.size());
 		lua_rawseti(L, -2, i);
 	}
 	lua_setfield(L, -2, "connects_to");
@@ -893,9 +890,8 @@ void push_box(lua_State *L, const std::vector<aabb3f> &box)
 {
 	lua_newtable(L);
 	u8 i = 1;
-	for (std::vector<aabb3f>::const_iterator it = box.begin();
-	                it != box.end(); ++it) {
-		push_aabb3f(L, (*it));
+	for (const aabb3f &it : box) {
+		push_aabb3f(L, it);
 		lua_rawseti(L, -2, i);
 	}
 }
@@ -987,21 +983,19 @@ NodeBox read_nodebox(lua_State *L, int index)
 		nodebox.type = (NodeBoxType)getenumfield(L, index, "type",
 				ScriptApiNode::es_NodeBoxType, NODEBOX_REGULAR);
 
-#define NODEBOXREAD(n, s) \
-	do { \
+#define NODEBOXREAD(n, s){ \
 		lua_getfield(L, index, (s)); \
 		if (lua_istable(L, -1)) \
 			(n) = read_aabb3f(L, -1, BS); \
 		lua_pop(L, 1); \
-	} while (0)
+	}
 
 #define NODEBOXREADVEC(n, s) \
-	do { \
 		lua_getfield(L, index, (s)); \
 		if (lua_istable(L, -1)) \
 			(n) = read_aabb3f_vector(L, -1, BS); \
-		lua_pop(L, 1); \
-	} while (0)
+		lua_pop(L, 1);
+
 		NODEBOXREADVEC(nodebox.fixed, "fixed");
 		NODEBOXREAD(nodebox.wall_top, "wall_top");
 		NODEBOXREAD(nodebox.wall_bottom, "wall_bottom");
@@ -1037,7 +1031,7 @@ MapNode readnode(lua_State *L, int index, INodeDefManager *ndef)
 		param2 = lua_tonumber(L, -1);
 	lua_pop(L, 1);
 
-	return MapNode(ndef, name, param1, param2);
+	return {ndef, name, param1, param2};
 }
 
 /******************************************************************************/
@@ -1096,18 +1090,17 @@ ItemStack read_item(lua_State* L, int index, IItemDefManager *idef)
 	if(index < 0)
 		index = lua_gettop(L) + 1 + index;
 
-	if(lua_isnil(L, index))
-	{
+	if (lua_isnil(L, index)) {
 		return ItemStack();
 	}
-	else if(lua_isuserdata(L, index))
-	{
+
+	if (lua_isuserdata(L, index)) {
 		// Convert from LuaItemStack
 		LuaItemStack *o = LuaItemStack::checkobject(L, index);
 		return o->getItem();
 	}
-	else if(lua_isstring(L, index))
-	{
+
+	if (lua_isstring(L, index)) {
 		// Convert from itemstring
 		std::string itemstring = lua_tostring(L, index);
 		try
@@ -1168,18 +1161,16 @@ void push_tool_capabilities(lua_State *L,
 		// Create groupcaps table
 		lua_newtable(L);
 		// For each groupcap
-		for (ToolGCMap::const_iterator i = toolcap.groupcaps.begin();
-			i != toolcap.groupcaps.end(); ++i) {
+		for (const auto &gc_it : toolcap.groupcaps) {
 			// Create groupcap table
 			lua_newtable(L);
-			const std::string &name = i->first;
-			const ToolGroupCap &groupcap = i->second;
+			const std::string &name = gc_it.first;
+			const ToolGroupCap &groupcap = gc_it.second;
 			// Create subtable "times"
 			lua_newtable(L);
-			for (std::unordered_map<int, float>::const_iterator
-					i = groupcap.times.begin(); i != groupcap.times.end(); ++i) {
-				lua_pushinteger(L, i->first);
-				lua_pushnumber(L, i->second);
+			for (auto time : groupcap.times) {
+				lua_pushinteger(L, time.first);
+				lua_pushnumber(L, time.second);
 				lua_settable(L, -3);
 			}
 			// Set subtable "times"
@@ -1195,11 +1186,10 @@ void push_tool_capabilities(lua_State *L,
 		//Create damage_groups table
 		lua_newtable(L);
 		// For each damage group
-		for (DamageGroup::const_iterator i = toolcap.damageGroups.begin();
-			i != toolcap.damageGroups.end(); ++i) {
+		for (const auto &damageGroup : toolcap.damageGroups) {
 			// Create damage group table
-			lua_pushinteger(L, i->second);
-			lua_setfield(L, -2, i->first.c_str());
+			lua_pushinteger(L, damageGroup.second);
+			lua_setfield(L, -2, damageGroup.first.c_str());
 		}
 		lua_setfield(L, -2, "damage_groups");
 }
@@ -1459,9 +1449,9 @@ void read_groups(lua_State *L, int index, ItemGroupList &result)
 void push_groups(lua_State *L, const ItemGroupList &groups)
 {
 	lua_newtable(L);
-	for (ItemGroupList::const_iterator it = groups.begin(); it != groups.end(); ++it) {
-		lua_pushnumber(L, it->second);
-		lua_setfield(L, -2, it->first.c_str());
+	for (const auto &group : groups) {
+		lua_pushnumber(L, group.second);
+		lua_setfield(L, -2, group.first.c_str());
 	}
 }
 
@@ -1572,9 +1562,8 @@ static int push_json_value_getdepth(const Json::Value &value)
 		return 1;
 
 	int maxdepth = 0;
-	for (Json::Value::const_iterator it = value.begin();
-			it != value.end(); ++it) {
-		int elemdepth = push_json_value_getdepth(*it);
+	for (const auto &it : value) {
+		int elemdepth = push_json_value_getdepth(it);
 		if (elemdepth > maxdepth)
 			maxdepth = elemdepth;
 	}
@@ -1646,8 +1635,8 @@ bool push_json_value(lua_State *L, const Json::Value &value, int nullindex)
 	// of push_json_value_helper is 2, so make sure there a depth * 2 slots
 	if (lua_checkstack(L, depth * 2))
 		return push_json_value_helper(L, value, nullindex);
-	else
-		return false;
+
+	return false;
 }
 
 // Converts Lua table --> JSON
diff --git a/src/script/common/c_content.h b/src/script/common/c_content.h
index c4440c5d9..80a96e327 100644
--- a/src/script/common/c_content.h
+++ b/src/script/common/c_content.h
@@ -123,7 +123,6 @@ MapNode            readnode                  (lua_State *L, int index,
 void               pushnode                  (lua_State *L, const MapNode &n,
                                               INodeDefManager *ndef);
 
-NodeBox            read_nodebox              (lua_State *L, int index);
 
 void               read_groups               (lua_State *L, int index,
                                               ItemGroupList &result);
@@ -159,9 +158,6 @@ std::vector<ItemStack> read_items            (lua_State *L,
                                               int index,
                                               Server* srv);
 
-void               read_soundspec            (lua_State *L,
-                                              int index,
-                                              SimpleSoundSpec &spec);
 void               push_soundspec            (lua_State *L,
                                               const SimpleSoundSpec &spec);
 
diff --git a/src/script/common/c_converter.cpp b/src/script/common/c_converter.cpp
index 3426a9677..e5d89dea9 100644
--- a/src/script/common/c_converter.cpp
+++ b/src/script/common/c_converter.cpp
@@ -30,7 +30,7 @@ extern "C" {
 #include "constants.h"
 
 
-#define CHECK_TYPE(index, name, type) do { \
+#define CHECK_TYPE(index, name, type) { \
 		int t = lua_type(L, (index)); \
 		if (t != (type)) { \
 			std::string traceback = script_get_backtrace(L); \
@@ -38,7 +38,7 @@ extern "C" {
 				" (expected " + lua_typename(L, (type)) + \
 				" got " + lua_typename(L, t) + ").\n" + traceback); \
 		} \
-	} while(0)
+	}
 #define CHECK_POS_COORD(name) CHECK_TYPE(-1, "position coordinate '" name "'", LUA_TNUMBER)
 #define CHECK_FLOAT_RANGE(value, name) \
 if (value < F1000_MIN || value > F1000_MAX) { \
diff --git a/src/script/common/c_converter.h b/src/script/common/c_converter.h
index bba01f545..f94996c88 100644
--- a/src/script/common/c_converter.h
+++ b/src/script/common/c_converter.h
@@ -76,8 +76,6 @@ void               setfloatfield(lua_State *L, int table,
                              const char *fieldname, float value);
 void               setboolfield(lua_State *L, int table,
                              const char *fieldname, bool value);
-void               setstringfield(lua_State *L, int table,
-                             const char *fieldname, const char *value);
 
 v3f                 checkFloatPos       (lua_State *L, int index);
 v2f                 check_v2f           (lua_State *L, int index);
diff --git a/src/script/common/c_internal.h b/src/script/common/c_internal.h
index 2548ac979..35477375b 100644
--- a/src/script/common/c_internal.h
+++ b/src/script/common/c_internal.h
@@ -58,12 +58,12 @@ extern "C" {
 #define PUSH_ERROR_HANDLER(L) \
 	(lua_rawgeti((L), LUA_REGISTRYINDEX, CUSTOM_RIDX_BACKTRACE), lua_gettop((L)))
 
-#define PCALL_RESL(L, RES) do {                         \
+#define PCALL_RESL(L, RES) {                            \
 	int result_ = (RES);                                \
 	if (result_ != 0) {                                 \
 		script_error((L), result_, NULL, __FUNCTION__); \
 	}                                                   \
-} while (0)
+}
 
 #define script_run_callbacks(L, nargs, mode) \
 	script_run_callbacks_f((L), (nargs), (mode), __FUNCTION__)
diff --git a/src/script/cpp_api/s_async.cpp b/src/script/cpp_api/s_async.cpp
index 5cca5fc03..93a200c22 100644
--- a/src/script/cpp_api/s_async.cpp
+++ b/src/script/cpp_api/s_async.cpp
@@ -17,8 +17,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-#include <stdio.h>
-#include <stdlib.h>
+#include <cstdio>
+#include <cstdlib>
 
 extern "C" {
 #include "lua.h"
@@ -38,9 +38,8 @@ AsyncEngine::~AsyncEngine()
 {
 
 	// Request all threads to stop
-	for (std::vector<AsyncWorkerThread *>::iterator it = workerThreads.begin();
-			it != workerThreads.end(); ++it) {
-		(*it)->stop();
+	for (AsyncWorkerThread *workerThread : workerThreads) {
+		workerThread->stop();
 	}
 
 
@@ -51,15 +50,13 @@ AsyncEngine::~AsyncEngine()
 	}
 
 	// Wait for threads to finish
-	for (std::vector<AsyncWorkerThread *>::iterator it = workerThreads.begin();
-			it != workerThreads.end(); ++it) {
-		(*it)->wait();
+	for (AsyncWorkerThread *workerThread : workerThreads) {
+		workerThread->wait();
 	}
 
 	// Force kill all threads
-	for (std::vector<AsyncWorkerThread *>::iterator it = workerThreads.begin();
-			it != workerThreads.end(); ++it) {
-		delete *it;
+	for (AsyncWorkerThread *workerThread : workerThreads) {
+		delete workerThread;
 	}
 
 	jobQueueMutex.lock();
@@ -192,9 +189,8 @@ void AsyncEngine::pushFinishedJobs(lua_State* L) {
 /******************************************************************************/
 void AsyncEngine::prepareEnvironment(lua_State* L, int top)
 {
-	for (std::vector<StateInitializer>::iterator it = stateInitializers.begin();
-			it != stateInitializers.end(); it++) {
-		(*it)(L, top);
+	for (StateInitializer &stateInitializer : stateInitializers) {
+		stateInitializer(L, top);
 	}
 }
 
@@ -202,7 +198,6 @@ void AsyncEngine::prepareEnvironment(lua_State* L, int top)
 AsyncWorkerThread::AsyncWorkerThread(AsyncEngine* jobDispatcher,
 		const std::string &name) :
 	Thread(name),
-	ScriptApiBase(),
 	jobDispatcher(jobDispatcher)
 {
 	lua_State *L = getStack();
diff --git a/src/script/cpp_api/s_async.h b/src/script/cpp_api/s_async.h
index 38eb4800a..b1f4bf45f 100644
--- a/src/script/cpp_api/s_async.h
+++ b/src/script/cpp_api/s_async.h
@@ -68,7 +68,7 @@ class AsyncEngine {
 	friend class AsyncWorkerThread;
 	typedef void (*StateInitializer)(lua_State *L, int top);
 public:
-	AsyncEngine() {};
+	AsyncEngine() = default;
 	~AsyncEngine();
 
 	/**
diff --git a/src/script/cpp_api/s_base.cpp b/src/script/cpp_api/s_base.cpp
index 6bea8230b..32a99826e 100644
--- a/src/script/cpp_api/s_base.cpp
+++ b/src/script/cpp_api/s_base.cpp
@@ -40,7 +40,7 @@ extern "C" {
 #endif
 }
 
-#include <stdio.h>
+#include <cstdio>
 #include <cstdarg>
 #include "script/common/c_content.h"
 #include <sstream>
diff --git a/src/script/cpp_api/s_base.h b/src/script/cpp_api/s_base.h
index b2c8b4a18..a170f82dc 100644
--- a/src/script/cpp_api/s_base.h
+++ b/src/script/cpp_api/s_base.h
@@ -40,12 +40,12 @@ extern "C" {
 // use that name to bypass security!
 #define BUILTIN_MOD_NAME "*builtin*"
 
-#define PCALL_RES(RES) do {                 \
+#define PCALL_RES(RES) {                    \
 	int result_ = (RES);                    \
 	if (result_ != 0) {                     \
 		scriptError(result_, __FUNCTION__); \
 	}                                       \
-} while (0)
+}
 
 #define runCallbacks(nargs, mode) \
 	runCallbacksRaw((nargs), (mode), __FUNCTION__)
diff --git a/src/script/cpp_api/s_inventory.cpp b/src/script/cpp_api/s_inventory.cpp
index c90c7d4e2..251ddb221 100644
--- a/src/script/cpp_api/s_inventory.cpp
+++ b/src/script/cpp_api/s_inventory.cpp
@@ -218,8 +218,7 @@ bool ScriptApiDetached::getDetachedInventoryCallback(
 	lua_getfield(L, -1, name.c_str());
 	lua_remove(L, -2);
 	// Should be a table
-	if(lua_type(L, -1) != LUA_TTABLE)
-	{
+	if (lua_type(L, -1) != LUA_TTABLE) {
 		errorstream<<"Detached inventory \""<<name<<"\" not defined"<<std::endl;
 		lua_pop(L, 1);
 		return false;
@@ -230,20 +229,17 @@ bool ScriptApiDetached::getDetachedInventoryCallback(
 	lua_getfield(L, -1, callbackname);
 	lua_remove(L, -2);
 	// Should be a function or nil
-	if(lua_type(L, -1) == LUA_TFUNCTION)
-	{
+	if (lua_type(L, -1) == LUA_TFUNCTION) {
 		return true;
 	}
-	else if(lua_isnil(L, -1))
-	{
-		lua_pop(L, 1);
-		return false;
-	}
-	else
-	{
-		errorstream<<"Detached inventory \""<<name<<"\" callback \""
-			<<callbackname<<"\" is not a function"<<std::endl;
+
+	if (lua_isnil(L, -1)) {
 		lua_pop(L, 1);
 		return false;
 	}
+
+	errorstream << "Detached inventory \"" << name << "\" callback \""
+		<< callbackname << "\" is not a function" << std::endl;
+	lua_pop(L, 1);
+	return false;
 }
diff --git a/src/script/cpp_api/s_item.cpp b/src/script/cpp_api/s_item.cpp
index 032018f2f..d48a3aee9 100644
--- a/src/script/cpp_api/s_item.cpp
+++ b/src/script/cpp_api/s_item.cpp
@@ -113,12 +113,12 @@ bool ScriptApiItem::item_OnUse(ItemStack &item,
 bool ScriptApiItem::item_OnSecondaryUse(ItemStack &item, ServerActiveObject *user)
 {
 	SCRIPTAPI_PRECHECKHEADER
-	
+
 	int error_handler = PUSH_ERROR_HANDLER(L);
-	
+
 	if (!getItemCallback(item.name.c_str(), "on_secondary_use"))
 		return false;
-	
+
 	LuaItemStack::create(L, item);
 	objectrefGetOrCreate(L, user);
 	PointedThing pointed;
@@ -237,7 +237,9 @@ bool ScriptApiItem::getItemCallback(const char *name, const char *callbackname)
 	// Should be a function or nil
 	if (lua_type(L, -1) == LUA_TFUNCTION) {
 		return true;
-	} else if (!lua_isnil(L, -1)) {
+	}
+
+	if (!lua_isnil(L, -1)) {
 		errorstream << "Item \"" << name << "\" callback \""
 			<< callbackname << "\" is not a function" << std::endl;
 	}
diff --git a/src/script/cpp_api/s_node.cpp b/src/script/cpp_api/s_node.cpp
index aa28e3fb5..591e26975 100644
--- a/src/script/cpp_api/s_node.cpp
+++ b/src/script/cpp_api/s_node.cpp
@@ -93,12 +93,6 @@ struct EnumString ScriptApiNode::es_NodeBoxType[] =
 		{0, NULL},
 	};
 
-ScriptApiNode::ScriptApiNode() {
-}
-
-ScriptApiNode::~ScriptApiNode() {
-}
-
 bool ScriptApiNode::node_on_punch(v3s16 p, MapNode node,
 		ServerActiveObject *puncher, PointedThing pointed)
 {
@@ -198,7 +192,7 @@ bool ScriptApiNode::node_on_flood(v3s16 p, MapNode node, MapNode newnode)
 	pushnode(L, newnode, ndef);
 	PCALL_RES(lua_pcall(L, 3, 1, error_handler));
 	lua_remove(L, error_handler);
-	return (bool) lua_isboolean(L, -1) && (bool) lua_toboolean(L, -1) == true;
+	return (bool) lua_isboolean(L, -1) && (bool) lua_toboolean(L, -1);
 }
 
 void ScriptApiNode::node_after_destruct(v3s16 p, MapNode node)
@@ -237,7 +231,7 @@ bool ScriptApiNode::node_on_timer(v3s16 p, MapNode node, f32 dtime)
 	lua_pushnumber(L,dtime);
 	PCALL_RES(lua_pcall(L, 2, 1, error_handler));
 	lua_remove(L, error_handler);
-	return (bool) lua_isboolean(L, -1) && (bool) lua_toboolean(L, -1) == true;
+	return (bool) lua_isboolean(L, -1) && (bool) lua_toboolean(L, -1);
 }
 
 void ScriptApiNode::node_on_receive_fields(v3s16 p,
diff --git a/src/script/cpp_api/s_node.h b/src/script/cpp_api/s_node.h
index 92f07cee7..5b6509c83 100644
--- a/src/script/cpp_api/s_node.h
+++ b/src/script/cpp_api/s_node.h
@@ -32,8 +32,8 @@ class ScriptApiNode
 		  public ScriptApiNodemeta
 {
 public:
-	ScriptApiNode();
-	virtual ~ScriptApiNode();
+	ScriptApiNode() = default;
+	virtual ~ScriptApiNode() = default;
 
 	bool node_on_punch(v3s16 p, MapNode node,
 			ServerActiveObject *puncher, PointedThing pointed);
diff --git a/src/script/cpp_api/s_nodemeta.cpp b/src/script/cpp_api/s_nodemeta.cpp
index d050c0bc9..2e6d3a373 100644
--- a/src/script/cpp_api/s_nodemeta.cpp
+++ b/src/script/cpp_api/s_nodemeta.cpp
@@ -232,12 +232,3 @@ void ScriptApiNodemeta::nodemeta_inventory_OnTake(v3s16 p,
 	PCALL_RES(lua_pcall(L, 5, 0, error_handler));
 	lua_pop(L, 1);  // Pop error handler
 }
-
-ScriptApiNodemeta::ScriptApiNodemeta()
-{
-}
-
-ScriptApiNodemeta::~ScriptApiNodemeta()
-{
-}
-
diff --git a/src/script/cpp_api/s_nodemeta.h b/src/script/cpp_api/s_nodemeta.h
index 51b8a5eb2..4d3257dcf 100644
--- a/src/script/cpp_api/s_nodemeta.h
+++ b/src/script/cpp_api/s_nodemeta.h
@@ -30,8 +30,8 @@ class ScriptApiNodemeta
 		  public ScriptApiItem
 {
 public:
-	ScriptApiNodemeta();
-	virtual ~ScriptApiNodemeta();
+	ScriptApiNodemeta() = default;
+	virtual ~ScriptApiNodemeta() = default;
 
 	// Return number of accepted items to be moved
 	int nodemeta_inventory_AllowMove(v3s16 p,
diff --git a/src/script/cpp_api/s_player.cpp b/src/script/cpp_api/s_player.cpp
index a8c07476c..b7f2f10f9 100644
--- a/src/script/cpp_api/s_player.cpp
+++ b/src/script/cpp_api/s_player.cpp
@@ -192,8 +192,3 @@ void ScriptApiPlayer::on_playerReceiveFields(ServerActiveObject *player,
 	runCallbacks(3, RUN_CALLBACKS_MODE_OR_SC);
 }
 
-ScriptApiPlayer::~ScriptApiPlayer()
-{
-}
-
-
diff --git a/src/script/cpp_api/s_player.h b/src/script/cpp_api/s_player.h
index 70b06bfc7..faf394de5 100644
--- a/src/script/cpp_api/s_player.h
+++ b/src/script/cpp_api/s_player.h
@@ -28,7 +28,7 @@ struct ToolCapabilities;
 class ScriptApiPlayer : virtual public ScriptApiBase
 {
 public:
-	virtual ~ScriptApiPlayer();
+	virtual ~ScriptApiPlayer() = default;
 
 	void on_newplayer(ServerActiveObject *player);
 	void on_dieplayer(ServerActiveObject *player);
diff --git a/src/script/cpp_api/s_security.cpp b/src/script/cpp_api/s_security.cpp
index 761597701..690a3b47f 100644
--- a/src/script/cpp_api/s_security.cpp
+++ b/src/script/cpp_api/s_security.cpp
@@ -260,7 +260,7 @@ void ScriptApiSecurity::initializeSecurityClient()
 	static const char *os_whitelist[] = {
 		"clock",
 		"date",
-		"difftime",	
+		"difftime",
 		"time",
 		"setlocale",
 	};
@@ -504,7 +504,7 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
 			// by the operating system anyways.
 			return false;
 		}
-		removed = component + (removed.empty() ? "" : DIR_DELIM + removed);
+		removed.append(component).append(removed.empty() ? "" : DIR_DELIM + removed);
 		abs_path = fs::AbsolutePath(cur_path);
 	}
 	if (abs_path.empty())
@@ -550,9 +550,9 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
 
 	// Allow read-only access to all mod directories
 	if (!write_required) {
-		const std::vector<ModSpec> mods = gamedef->getMods();
-		for (size_t i = 0; i < mods.size(); ++i) {
-			str = fs::AbsolutePath(mods[i].path);
+		const std::vector<ModSpec> &mods = gamedef->getMods();
+		for (const ModSpec &mod : mods) {
+			str = fs::AbsolutePath(mod.path);
 			if (!str.empty() && fs::PathStartsWith(abs_path, str)) {
 				return true;
 			}
@@ -617,7 +617,9 @@ int ScriptApiSecurity::sl_g_load(lua_State *L)
 		int t = lua_type(L, -1);
 		if (t == LUA_TNIL) {
 			break;
-		} else if (t != LUA_TSTRING) {
+		}
+
+		if (t != LUA_TSTRING) {
 			lua_pushnil(L);
 			lua_pushliteral(L, "Loader didn't return a string");
 			return 2;
diff --git a/src/script/lua_api/l_client.cpp b/src/script/lua_api/l_client.cpp
index 6a87b20e9..81bf49329 100644
--- a/src/script/lua_api/l_client.cpp
+++ b/src/script/lua_api/l_client.cpp
@@ -34,7 +34,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "util/string.h"
 #include "nodedef.h"
 
-
 int ModApiClient::l_get_current_modname(lua_State *L)
 {
 	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_CURRENT_MOD_NAME);
diff --git a/src/script/lua_api/l_env.cpp b/src/script/lua_api/l_env.cpp
index 94edf201e..07d33a4eb 100644
--- a/src/script/lua_api/l_env.cpp
+++ b/src/script/lua_api/l_env.cpp
@@ -743,7 +743,7 @@ int ModApiEnvMod::l_find_node_near(lua_State *L)
 
 	for (int d = start_radius; d <= radius; d++) {
 		std::vector<v3s16> list = FacePositionCache::getFacePositions(d);
-		for (v3s16 i : list) {
+		for (const v3s16 &i : list) {
 			v3s16 p = pos + i;
 			content_t c = env->getMap().getNodeNoEx(p).getContent();
 			if (filter.count(c) != 0) {
@@ -1127,7 +1127,7 @@ int ModApiEnvMod::l_find_path(lua_State *L)
 		lua_newtable(L);
 		int top = lua_gettop(L);
 		unsigned int index = 1;
-		for (v3s16 i : path) {
+		for (const v3s16 &i : path) {
 			lua_pushnumber(L,index);
 			push_v3s16(L, i);
 			lua_settable(L, top);
diff --git a/src/script/lua_api/l_inventory.cpp b/src/script/lua_api/l_inventory.cpp
index b0d43090c..f3097582e 100644
--- a/src/script/lua_api/l_inventory.cpp
+++ b/src/script/lua_api/l_inventory.cpp
@@ -495,28 +495,29 @@ int ModApiInventory::l_get_inventory(lua_State *L)
 		v3s16 pos = check_v3s16(L, -1);
 		loc.setNodeMeta(pos);
 
-		if(getServer(L)->getInventory(loc) != NULL)
+		if (getServer(L)->getInventory(loc) != NULL)
 			InvRef::create(L, loc);
 		else
 			lua_pushnil(L);
 		return 1;
-	} else {
-		NO_MAP_LOCK_REQUIRED;
-		if(type == "player"){
-			std::string name = checkstringfield(L, 1, "name");
-			loc.setPlayer(name);
-		} else if(type == "detached"){
-			std::string name = checkstringfield(L, 1, "name");
-			loc.setDetached(name);
-		}
+	}
 
-		if(getServer(L)->getInventory(loc) != NULL)
-			InvRef::create(L, loc);
-		else
-			lua_pushnil(L);
-		return 1;
-		// END NO_MAP_LOCK_REQUIRED;
+	NO_MAP_LOCK_REQUIRED;
+	if (type == "player") {
+		std::string name = checkstringfield(L, 1, "name");
+		loc.setPlayer(name);
+	} else if (type == "detached") {
+		std::string name = checkstringfield(L, 1, "name");
+		loc.setDetached(name);
 	}
+
+	if (getServer(L)->getInventory(loc) != NULL)
+		InvRef::create(L, loc);
+	else
+		lua_pushnil(L);
+	return 1;
+	// END NO_MAP_LOCK_REQUIRED;
+
 }
 
 // create_detached_inventory_raw(name, [player_name])
diff --git a/src/script/lua_api/l_mainmenu.cpp b/src/script/lua_api/l_mainmenu.cpp
index b0ce6b740..86305de82 100644
--- a/src/script/lua_api/l_mainmenu.cpp
+++ b/src/script/lua_api/l_mainmenu.cpp
@@ -233,23 +233,22 @@ int ModApiMainMenu::l_get_worlds(lua_State *L)
 	int top = lua_gettop(L);
 	unsigned int index = 1;
 
-	for (unsigned int i = 0; i < worlds.size(); i++)
-	{
+	for (const WorldSpec &world : worlds) {
 		lua_pushnumber(L,index);
 
 		lua_newtable(L);
 		int top_lvl2 = lua_gettop(L);
 
 		lua_pushstring(L,"path");
-		lua_pushstring(L,worlds[i].path.c_str());
+		lua_pushstring(L, world.path.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"name");
-		lua_pushstring(L,worlds[i].name.c_str());
+		lua_pushstring(L, world.name.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"gameid");
-		lua_pushstring(L,worlds[i].gameid.c_str());
+		lua_pushstring(L, world.gameid.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_settable(L, top);
@@ -267,40 +266,38 @@ int ModApiMainMenu::l_get_games(lua_State *L)
 	int top = lua_gettop(L);
 	unsigned int index = 1;
 
-	for (unsigned int i = 0; i < games.size(); i++)
-	{
+	for (const SubgameSpec &game : games) {
 		lua_pushnumber(L,index);
 		lua_newtable(L);
 		int top_lvl2 = lua_gettop(L);
 
 		lua_pushstring(L,"id");
-		lua_pushstring(L,games[i].id.c_str());
+		lua_pushstring(L, game.id.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"path");
-		lua_pushstring(L,games[i].path.c_str());
+		lua_pushstring(L, game.path.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"gamemods_path");
-		lua_pushstring(L,games[i].gamemods_path.c_str());
+		lua_pushstring(L, game.gamemods_path.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"name");
-		lua_pushstring(L,games[i].name.c_str());
+		lua_pushstring(L, game.name.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"menuicon_path");
-		lua_pushstring(L,games[i].menuicon_path.c_str());
+		lua_pushstring(L, game.menuicon_path.c_str());
 		lua_settable(L, top_lvl2);
 
 		lua_pushstring(L,"addon_mods_paths");
 		lua_newtable(L);
 		int table2 = lua_gettop(L);
 		int internal_index=1;
-		for (std::set<std::string>::iterator iter = games[i].addon_mods_paths.begin();
-				iter != games[i].addon_mods_paths.end(); ++iter) {
+		for (const std::string &addon_mods_path : game.addon_mods_paths) {
 			lua_pushnumber(L,internal_index);
-			lua_pushstring(L,(*iter).c_str());
+			lua_pushstring(L, addon_mods_path.c_str());
 			lua_settable(L, table2);
 			internal_index++;
 		}
@@ -331,112 +328,111 @@ int ModApiMainMenu::l_get_favorites(lua_State *L)
 	int top = lua_gettop(L);
 	unsigned int index = 1;
 
-	for (unsigned int i = 0; i < servers.size(); i++)
-	{
+	for (const Json::Value &server : servers) {
 
 		lua_pushnumber(L,index);
 
 		lua_newtable(L);
 		int top_lvl2 = lua_gettop(L);
 
-		if (servers[i]["clients"].asString().size()) {
-			std::string clients_raw = servers[i]["clients"].asString();
+		if (!server["clients"].asString().empty()) {
+			std::string clients_raw = server["clients"].asString();
 			char* endptr = 0;
 			int numbervalue = strtol(clients_raw.c_str(),&endptr,10);
 
-			if ((clients_raw != "") && (*endptr == 0)) {
+			if ((!clients_raw.empty()) && (*endptr == 0)) {
 				lua_pushstring(L,"clients");
 				lua_pushnumber(L,numbervalue);
 				lua_settable(L, top_lvl2);
 			}
 		}
 
-		if (servers[i]["clients_max"].asString().size()) {
+		if (!server["clients_max"].asString().empty()) {
 
-			std::string clients_max_raw = servers[i]["clients_max"].asString();
+			std::string clients_max_raw = server["clients_max"].asString();
 			char* endptr = 0;
 			int numbervalue = strtol(clients_max_raw.c_str(),&endptr,10);
 
-			if ((clients_max_raw != "") && (*endptr == 0)) {
+			if ((!clients_max_raw.empty()) && (*endptr == 0)) {
 				lua_pushstring(L,"clients_max");
 				lua_pushnumber(L,numbervalue);
 				lua_settable(L, top_lvl2);
 			}
 		}
 
-		if (servers[i]["version"].asString().size()) {
+		if (!server["version"].asString().empty()) {
 			lua_pushstring(L,"version");
-			std::string topush = servers[i]["version"].asString();
+			std::string topush = server["version"].asString();
 			lua_pushstring(L,topush.c_str());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["proto_min"].asString().size()) {
+		if (!server["proto_min"].asString().empty()) {
 			lua_pushstring(L,"proto_min");
-			lua_pushinteger(L,servers[i]["proto_min"].asInt());
+			lua_pushinteger(L, server["proto_min"].asInt());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["proto_max"].asString().size()) {
+		if (!server["proto_max"].asString().empty()) {
 			lua_pushstring(L,"proto_max");
-			lua_pushinteger(L,servers[i]["proto_max"].asInt());
+			lua_pushinteger(L, server["proto_max"].asInt());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["password"].asString().size()) {
+		if (!server["password"].asString().empty()) {
 			lua_pushstring(L,"password");
-			lua_pushboolean(L,servers[i]["password"].asBool());
+			lua_pushboolean(L, server["password"].asBool());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["creative"].asString().size()) {
+		if (!server["creative"].asString().empty()) {
 			lua_pushstring(L,"creative");
-			lua_pushboolean(L,servers[i]["creative"].asBool());
+			lua_pushboolean(L, server["creative"].asBool());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["damage"].asString().size()) {
+		if (!server["damage"].asString().empty()) {
 			lua_pushstring(L,"damage");
-			lua_pushboolean(L,servers[i]["damage"].asBool());
+			lua_pushboolean(L, server["damage"].asBool());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["pvp"].asString().size()) {
+		if (!server["pvp"].asString().empty()) {
 			lua_pushstring(L,"pvp");
-			lua_pushboolean(L,servers[i]["pvp"].asBool());
+			lua_pushboolean(L, server["pvp"].asBool());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["description"].asString().size()) {
+		if (!server["description"].asString().empty()) {
 			lua_pushstring(L,"description");
-			std::string topush = servers[i]["description"].asString();
+			std::string topush = server["description"].asString();
 			lua_pushstring(L,topush.c_str());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["name"].asString().size()) {
+		if (!server["name"].asString().empty()) {
 			lua_pushstring(L,"name");
-			std::string topush = servers[i]["name"].asString();
+			std::string topush = server["name"].asString();
 			lua_pushstring(L,topush.c_str());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["address"].asString().size()) {
+		if (!server["address"].asString().empty()) {
 			lua_pushstring(L,"address");
-			std::string topush = servers[i]["address"].asString();
+			std::string topush = server["address"].asString();
 			lua_pushstring(L,topush.c_str());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i]["port"].asString().size()) {
+		if (!server["port"].asString().empty()) {
 			lua_pushstring(L,"port");
-			std::string topush = servers[i]["port"].asString();
+			std::string topush = server["port"].asString();
 			lua_pushstring(L,topush.c_str());
 			lua_settable(L, top_lvl2);
 		}
 
-		if (servers[i].isMember("ping")) {
-			float ping = servers[i]["ping"].asFloat();
+		if (server.isMember("ping")) {
+			float ping = server["ping"].asFloat();
 			lua_pushstring(L, "ping");
 			lua_pushnumber(L, ping);
 			lua_settable(L, top_lvl2);
@@ -558,7 +554,7 @@ int ModApiMainMenu::l_set_topleft_text(lua_State *L)
 	GUIEngine* engine = getGuiEngine(L);
 	sanity_check(engine != NULL);
 
-	std::string text = "";
+	std::string text;
 
 	if (!lua_isnone(L,1) &&	!lua_isnil(L,1))
 		text = luaL_checkstring(L, 1);
diff --git a/src/script/lua_api/l_mapgen.cpp b/src/script/lua_api/l_mapgen.cpp
index 454e8f719..a5e122ddb 100644
--- a/src/script/lua_api/l_mapgen.cpp
+++ b/src/script/lua_api/l_mapgen.cpp
@@ -847,9 +847,8 @@ int ModApiMapgen::l_get_gen_notify(lua_State *L)
 
 	lua_newtable(L);
 	int i = 1;
-	for (std::set<u32>::iterator it = emerge->gen_notify_on_deco_ids.begin();
-			it != emerge->gen_notify_on_deco_ids.end(); ++it) {
-		lua_pushnumber(L, *it);
+	for (u32 gen_notify_on_deco_id : emerge->gen_notify_on_deco_ids) {
+		lua_pushnumber(L, gen_notify_on_deco_id);
 		lua_rawseti(L, -2, i);
 		i++;
 	}
@@ -1322,7 +1321,7 @@ int ModApiMapgen::l_create_schematic(lua_State *L)
 				lua_pop(L, 1);
 
 				u8 prob = getintfield_default(L, -1, "prob", MTSCHEM_PROB_ALWAYS);
-				prob_list.push_back(std::make_pair(pos, prob));
+				prob_list.emplace_back(pos, prob);
 			}
 
 			lua_pop(L, 1);
@@ -1336,7 +1335,7 @@ int ModApiMapgen::l_create_schematic(lua_State *L)
 			if (lua_istable(L, -1)) {
 				s16 ypos = getintfield_default(L, -1, "ypos", 0);
 				u8 prob  = getintfield_default(L, -1, "prob", MTSCHEM_PROB_ALWAYS);
-				slice_prob_list.push_back(std::make_pair(ypos, prob));
+				slice_prob_list.emplace_back(ypos, prob);
 			}
 
 			lua_pop(L, 1);
diff --git a/src/script/lua_api/l_metadata.cpp b/src/script/lua_api/l_metadata.cpp
index 5f4e984cb..494d2dce0 100644
--- a/src/script/lua_api/l_metadata.cpp
+++ b/src/script/lua_api/l_metadata.cpp
@@ -218,10 +218,9 @@ void MetaDataRef::handleToTable(lua_State *L, Metadata *meta)
 	lua_newtable(L);
 	{
 		const StringMap &fields = meta->getStrings();
-		for (StringMap::const_iterator
-				it = fields.begin(); it != fields.end(); ++it) {
-			const std::string &name = it->first;
-			const std::string &value = it->second;
+		for (const auto &field : fields) {
+			const std::string &name = field.first;
+			const std::string &value = field.second;
 			lua_pushlstring(L, name.c_str(), name.size());
 			lua_pushlstring(L, value.c_str(), value.size());
 			lua_settable(L, -3);
diff --git a/src/script/lua_api/l_metadata.h b/src/script/lua_api/l_metadata.h
index 5a7c7e7f7..e0e9696cb 100644
--- a/src/script/lua_api/l_metadata.h
+++ b/src/script/lua_api/l_metadata.h
@@ -31,7 +31,7 @@ class Metadata;
 class MetaDataRef : public ModApiBase
 {
 public:
-	virtual ~MetaDataRef() {}
+	virtual ~MetaDataRef() = default;
 
 protected:
 	static MetaDataRef *checkobject(lua_State *L, int narg);
diff --git a/src/script/lua_api/l_object.cpp b/src/script/lua_api/l_object.cpp
index bad5ec8af..a65a5e88f 100644
--- a/src/script/lua_api/l_object.cpp
+++ b/src/script/lua_api/l_object.cpp
@@ -551,7 +551,7 @@ int ObjectRef::l_get_local_animation(lua_State *L)
 	float frame_speed;
 	player->getLocalAnimations(frames, &frame_speed);
 
-	for (v2s32 frame : frames) {
+	for (const v2s32 &frame : frames) {
 		push_v2s32(L, frame);
 	}
 
diff --git a/src/script/scripting_client.cpp b/src/script/scripting_client.cpp
index 904f735f3..b121f3712 100644
--- a/src/script/scripting_client.cpp
+++ b/src/script/scripting_client.cpp
@@ -32,8 +32,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "lua_api/l_localplayer.h"
 #include "lua_api/l_camera.h"
 
-ClientScripting::ClientScripting(Client *client):
-	ScriptApiBase()
+ClientScripting::ClientScripting(Client *client)
 {
 	setGameDef(client);
 	setType(ScriptingType::Client);
diff --git a/src/sky.cpp b/src/sky.cpp
index 0bc344b3f..02e882592 100644
--- a/src/sky.cpp
+++ b/src/sky.cpp
@@ -460,7 +460,7 @@ void Sky::render()
 			driver->drawVertexPrimitiveList(vertices, SKY_STAR_COUNT * 4,
 				indices, SKY_STAR_COUNT, video::EVT_STANDARD,
 				scene::EPT_QUADS, video::EIT_16BIT);
-		} while(0);
+		} while(false);
 
 		// Draw far cloudy fog thing below east and west horizons
 		for (u32 j = 0; j < 2; j++) {
diff --git a/src/sound.h b/src/sound.h
index b9c847079..f52746369 100644
--- a/src/sound.h
+++ b/src/sound.h
@@ -39,7 +39,7 @@ struct SimpleSoundSpec
 	{
 	}
 
-	bool exists() const { return name != ""; }
+	bool exists() const { return !name.empty(); }
 
 	std::string name = "";
 	float gain = 1.0f;
@@ -50,7 +50,8 @@ struct SimpleSoundSpec
 class ISoundManager
 {
 public:
-	virtual ~ISoundManager() {}
+	virtual ~ISoundManager() = default;
+
 	// Multiple sounds can be loaded per name; when played, the sound
 	// should be chosen randomly from alternatives
 	// Return value determines success/failure
@@ -80,7 +81,7 @@ public:
 	{
 		return playSound(spec.name, loop, spec.gain, spec.fade, spec.pitch);
 	}
-	int playSoundAt(const SimpleSoundSpec &spec, bool loop, v3f pos)
+	int playSoundAt(const SimpleSoundSpec &spec, bool loop, const v3f &pos)
 	{
 		return playSoundAt(spec.name, loop, spec.gain, pos, spec.pitch);
 	}
diff --git a/src/sound_openal.cpp b/src/sound_openal.cpp
index adae0c769..06259a27f 100644
--- a/src/sound_openal.cpp
+++ b/src/sound_openal.cpp
@@ -275,7 +275,8 @@ private:
 	std::unordered_map<int, PlayingSound*> m_sounds_playing;
 	v3f m_listener_pos;
 	struct FadeState {
-		FadeState() {}
+		FadeState() = default;
+
 		FadeState(float step, float current_gain, float target_gain):
 			step(step),
 			current_gain(current_gain),
@@ -351,13 +352,12 @@ public:
 		alcCloseDevice(m_device);
 		m_device = NULL;
 
-		for (std::unordered_map<std::string, std::vector<SoundBuffer*>>::iterator i =
-				m_buffers.begin(); i != m_buffers.end(); ++i) {
-			for (std::vector<SoundBuffer*>::iterator iter = (*i).second.begin();
-					iter != (*i).second.end(); ++iter) {
+		for (auto &buffer : m_buffers) {
+			for (std::vector<SoundBuffer*>::iterator iter = buffer.second.begin();
+					iter != buffer.second.end(); ++iter) {
 				delete *iter;
 			}
-			(*i).second.clear();
+			buffer.second.clear();
 		}
 		m_buffers.clear();
 		infostream<<"Audio: Deinitialized."<<std::endl;
@@ -379,7 +379,6 @@ public:
 		std::vector<SoundBuffer*> bufs;
 		bufs.push_back(buf);
 		m_buffers[name] = bufs;
-		return;
 	}
 
 	SoundBuffer* getBuffer(const std::string &name)
@@ -450,7 +449,8 @@ public:
 		return id;
 	}
 
-	int playSoundRawAt(SoundBuffer *buf, bool loop, float volume, v3f pos, float pitch)
+	int playSoundRawAt(SoundBuffer *buf, bool loop, float volume, const v3f &pos,
+			float pitch)
 	{
 		assert(buf);
 		PlayingSound *sound = createPlayingSoundAt(buf, loop, volume, pos, pitch);
@@ -485,13 +485,11 @@ public:
 		std::set<std::string> paths;
 		std::set<std::string> datas;
 		m_fetcher->fetchSounds(name, paths, datas);
-		for(std::set<std::string>::iterator i = paths.begin();
-				i != paths.end(); ++i){
-			loadSoundFile(name, *i);
+		for (const std::string &path : paths) {
+			loadSoundFile(name, path);
 		}
-		for(std::set<std::string>::iterator i = datas.begin();
-				i != datas.end(); ++i){
-			loadSoundData(name, *i);
+		for (const std::string &data : datas) {
+			loadSoundData(name, data);
 		}
 		return getBuffer(name);
 	}
@@ -503,10 +501,9 @@ public:
 				<<m_sounds_playing.size()<<" playing sounds, "
 				<<m_buffers.size()<<" sound names loaded"<<std::endl;
 		std::set<int> del_list;
-		for(std::unordered_map<int, PlayingSound*>::iterator i = m_sounds_playing.begin();
-				i != m_sounds_playing.end(); ++i) {
-			int id = i->first;
-			PlayingSound *sound = i->second;
+		for (auto &sp : m_sounds_playing) {
+			int id = sp.first;
+			PlayingSound *sound = sp.second;
 			// If not playing, remove it
 			{
 				ALint state;
@@ -519,10 +516,8 @@ public:
 		if(!del_list.empty())
 			verbosestream<<"OpenALSoundManager::maintain(): deleting "
 					<<del_list.size()<<" playing sounds"<<std::endl;
-		for(std::set<int>::iterator i = del_list.begin();
-				i != del_list.end(); ++i)
-		{
-			deleteSound(*i);
+		for (int i : del_list) {
+			deleteSound(i);
 		}
 	}
 
@@ -566,7 +561,7 @@ public:
 	int playSound(const std::string &name, bool loop, float volume, float fade, float pitch)
 	{
 		maintain();
-		if(name == "")
+		if (name.empty())
 			return 0;
 		SoundBuffer *buf = getFetchBuffer(name);
 		if(!buf){
@@ -587,7 +582,7 @@ public:
 	int playSoundAt(const std::string &name, bool loop, float volume, v3f pos, float pitch)
 	{
 		maintain();
-		if(name == "")
+		if (name.empty())
 			return 0;
 		SoundBuffer *buf = getFetchBuffer(name);
 		if(!buf){
diff --git a/src/staticobject.cpp b/src/staticobject.cpp
index d656b6221..6ad2e1f94 100644
--- a/src/staticobject.cpp
+++ b/src/staticobject.cpp
@@ -59,17 +59,12 @@ void StaticObjectList::serialize(std::ostream &os)
 	}
 	writeU16(os, count);
 
-	for(std::vector<StaticObject>::iterator
-			i = m_stored.begin();
-			i != m_stored.end(); ++i) {
-		StaticObject &s_obj = *i;
+	for (StaticObject &s_obj : m_stored) {
 		s_obj.serialize(os);
 	}
-	for(std::map<u16, StaticObject>::iterator
-			i = m_active.begin();
-			i != m_active.end(); ++i)
-	{
-		StaticObject s_obj = i->second;
+
+	for (auto &i : m_active) {
+		StaticObject s_obj = i.second;
 		s_obj.serialize(os);
 	}
 }
diff --git a/src/staticobject.h b/src/staticobject.h
index c457f1384..43f542632 100644
--- a/src/staticobject.h
+++ b/src/staticobject.h
@@ -32,8 +32,8 @@ struct StaticObject
 	v3f pos;
 	std::string data;
 
-	StaticObject() {}
-	StaticObject(u8 type_, v3f pos_, const std::string &data_):
+	StaticObject() = default;
+	StaticObject(u8 type_, const v3f &pos_, const std::string &data_):
 		type(type_),
 		pos(pos_),
 		data(data_)
@@ -51,7 +51,7 @@ public:
 		Inserts an object to the container.
 		Id must be unique (active) or 0 (stored).
 	*/
-	void insert(u16 id, StaticObject obj)
+	void insert(u16 id, const StaticObject &obj)
 	{
 		if(id == 0)
 		{
diff --git a/src/subgame.cpp b/src/subgame.cpp
index cd2aa752b..eb2ea01c1 100644
--- a/src/subgame.cpp
+++ b/src/subgame.cpp
@@ -71,7 +71,7 @@ std::string getSubgamePathEnv()
 
 SubgameSpec findSubgame(const std::string &id)
 {
-	if(id == "")
+	if (id.empty())
 		return SubgameSpec();
 	std::string share = porting::path_share;
 	std::string user = porting::path_user;
@@ -81,32 +81,27 @@ SubgameSpec findSubgame(const std::string &id)
 
 	while (!search_paths.at_end()) {
 		std::string path = search_paths.next(PATH_DELIM);
-		find_paths.push_back(GameFindPath(
-				path + DIR_DELIM + id, false));
-		find_paths.push_back(GameFindPath(
-				path + DIR_DELIM + id + "_game", false));
+		find_paths.emplace_back(path + DIR_DELIM + id, false);
+		find_paths.emplace_back(path + DIR_DELIM + id + "_game", false);
 	}
 
-	find_paths.push_back(GameFindPath(
-			user + DIR_DELIM + "games" + DIR_DELIM + id + "_game", true));
-	find_paths.push_back(GameFindPath(
-			user + DIR_DELIM + "games" + DIR_DELIM + id, true));
-	find_paths.push_back(GameFindPath(
-			share + DIR_DELIM + "games" + DIR_DELIM + id + "_game", false));
-	find_paths.push_back(GameFindPath(
-			share + DIR_DELIM + "games" + DIR_DELIM + id, false));
+	find_paths.emplace_back(user + DIR_DELIM + "games" + DIR_DELIM + id + "_game", true);
+	find_paths.emplace_back(user + DIR_DELIM + "games" + DIR_DELIM + id, true);
+	find_paths.emplace_back(share + DIR_DELIM + "games" + DIR_DELIM + id + "_game",
+		false);
+	find_paths.emplace_back(share + DIR_DELIM + "games" + DIR_DELIM + id, false);
 	// Find game directory
 	std::string game_path;
 	bool user_game = true; // Game is in user's directory
-	for(u32 i=0; i<find_paths.size(); i++){
-		const std::string &try_path = find_paths[i].path;
-		if(fs::PathExists(try_path)){
+	for (const GameFindPath &find_path : find_paths) {
+		const std::string &try_path = find_path.path;
+		if (fs::PathExists(try_path)) {
 			game_path = try_path;
-			user_game = find_paths[i].user_specific;
+			user_game = find_path.user_specific;
 			break;
 		}
 	}
-	if(game_path == "")
+	if (game_path.empty())
 		return SubgameSpec();
 	std::string gamemod_path = game_path + DIR_DELIM + "mods";
 	// Find mod directories
@@ -116,7 +111,7 @@ SubgameSpec findSubgame(const std::string &id)
 	if(user != share || user_game)
 		mods_paths.insert(user + DIR_DELIM + "mods");
 	std::string game_name = getGameName(game_path);
-	if(game_name == "")
+	if (game_name.empty())
 		game_name = id;
 	std::string menuicon_path;
 #ifndef SERVER
@@ -137,7 +132,7 @@ SubgameSpec findWorldSubgame(const std::string &world_path)
 		gamespec.path = world_gamepath;
 		gamespec.gamemods_path= world_gamepath + DIR_DELIM + "mods";
 		gamespec.name = getGameName(world_gamepath);
-		if(gamespec.name == "")
+		if (gamespec.name.empty())
 			gamespec.name = "unknown";
 		return gamespec;
 	}
@@ -156,23 +151,22 @@ std::set<std::string> getAvailableGameIds()
 	while (!search_paths.at_end())
 		gamespaths.insert(search_paths.next(PATH_DELIM));
 
-	for (std::set<std::string>::const_iterator i = gamespaths.begin();
-			i != gamespaths.end(); ++i){
-		std::vector<fs::DirListNode> dirlist = fs::GetDirListing(*i);
-		for(u32 j=0; j<dirlist.size(); j++){
-			if(!dirlist[j].dir)
+	for (const std::string &gamespath : gamespaths) {
+		std::vector<fs::DirListNode> dirlist = fs::GetDirListing(gamespath);
+		for (const fs::DirListNode &dln : dirlist) {
+			if(!dln.dir)
 				continue;
 			// If configuration file is not found or broken, ignore game
 			Settings conf;
-			if(!getGameConfig(*i + DIR_DELIM + dirlist[j].name, conf))
+			if(!getGameConfig(gamespath + DIR_DELIM + dln.name, conf))
 				continue;
 			// Add it to result
 			const char *ends[] = {"_game", NULL};
-			std::string shorter = removeStringEnd(dirlist[j].name, ends);
-			if(shorter != "")
+			std::string shorter = removeStringEnd(dln.name, ends);
+			if (!shorter.empty())
 				gameids.insert(shorter);
 			else
-				gameids.insert(dirlist[j].name);
+				gameids.insert(dln.name);
 		}
 	}
 	return gameids;
@@ -182,9 +176,8 @@ std::vector<SubgameSpec> getAvailableGames()
 {
 	std::vector<SubgameSpec> specs;
 	std::set<std::string> gameids = getAvailableGameIds();
-	for(std::set<std::string>::const_iterator i = gameids.begin();
-			i != gameids.end(); ++i)
-		specs.push_back(findSubgame(*i));
+	for (const auto &gameid : gameids)
+		specs.push_back(findSubgame(gameid));
 	return specs;
 }
 
@@ -235,15 +228,14 @@ std::vector<WorldSpec> getAvailableWorlds()
 
 	worldspaths.insert(porting::path_user + DIR_DELIM + "worlds");
 	infostream << "Searching worlds..." << std::endl;
-	for (std::set<std::string>::const_iterator i = worldspaths.begin();
-			i != worldspaths.end(); ++i) {
-		infostream << "  In " << (*i) << ": " <<std::endl;
-		std::vector<fs::DirListNode> dirvector = fs::GetDirListing(*i);
-		for(u32 j=0; j<dirvector.size(); j++){
-			if(!dirvector[j].dir)
+	for (const std::string &worldspath : worldspaths) {
+		infostream << "  In " << worldspath << ": " <<std::endl;
+		std::vector<fs::DirListNode> dirvector = fs::GetDirListing(worldspath);
+		for (const fs::DirListNode &dln : dirvector) {
+			if(!dln.dir)
 				continue;
-			std::string fullpath = *i + DIR_DELIM + dirvector[j].name;
-			std::string name = dirvector[j].name;
+			std::string fullpath = worldspath + DIR_DELIM + dln.name;
+			std::string name = dln.name;
 			// Just allow filling in the gameid always for now
 			bool can_be_legacy = true;
 			std::string gameid = getWorldGameId(fullpath, can_be_legacy);
@@ -267,7 +259,7 @@ std::vector<WorldSpec> getAvailableWorlds()
 		WorldSpec spec(fullpath, name, gameid);
 		infostream<<"Old world found."<<std::endl;
 		worlds.push_back(spec);
-	}while(0);
+	}while(false);
 	infostream<<worlds.size()<<" found."<<std::endl;
 	return worlds;
 }
diff --git a/src/subgame.h b/src/subgame.h
index 8c21973ea..6e7863962 100644
--- a/src/subgame.h
+++ b/src/subgame.h
@@ -50,7 +50,7 @@ struct SubgameSpec
 
 	bool isValid() const
 	{
-		return (id != "" && path != "");
+		return (!id.empty() && !path.empty());
 	}
 };
 
@@ -89,7 +89,7 @@ struct WorldSpec
 
 	bool isValid() const
 	{
-		return (name != "" && path != "" && gameid != "");
+		return (!name.empty() && !path.empty() && !gameid.empty());
 	}
 };
 
diff --git a/src/terminal_chat_console.cpp b/src/terminal_chat_console.cpp
index 222c08646..9e3d33736 100644
--- a/src/terminal_chat_console.cpp
+++ b/src/terminal_chat_console.cpp
@@ -348,7 +348,8 @@ void TerminalChatConsole::step(int ch)
 
 		std::wstring error_message = utf8_to_wide(Logger::getLevelLabel(p.first));
 		if (!g_settings->getBool("disable_escape_sequences")) {
-			error_message = L"\x1b(c@red)" + error_message + L"\x1b(c@white)";
+			error_message = std::wstring(L"\x1b(c@red)").append(error_message)
+				.append(L"\x1b(c@white)");
 		}
 		m_chat_backend.addMessage(error_message, utf8_to_wide(p.second));
 	}
@@ -439,8 +440,7 @@ void TerminalChatConsole::draw_text()
 		const ChatFormattedLine& line = buf.getFormattedLine(row);
 		if (line.fragments.empty())
 			continue;
-		for (u32 i = 0; i < line.fragments.size(); ++i) {
-			const ChatFormattedFragment& fragment = line.fragments[i];
+		for (const ChatFormattedFragment &fragment : line.fragments) {
 			addstr(wide_to_utf8(fragment.text.getString()).c_str());
 		}
 	}
diff --git a/src/tool.cpp b/src/tool.cpp
index 1afd71630..38508c5fe 100644
--- a/src/tool.cpp
+++ b/src/tool.cpp
@@ -31,26 +31,24 @@ void ToolCapabilities::serialize(std::ostream &os, u16 protocol_version) const
 	writeF1000(os, full_punch_interval);
 	writeS16(os, max_drop_level);
 	writeU32(os, groupcaps.size());
-	for (ToolGCMap::const_iterator i = groupcaps.begin(); i != groupcaps.end(); ++i) {
-		const std::string *name = &i->first;
-		const ToolGroupCap *cap = &i->second;
+	for (const auto &groupcap : groupcaps) {
+		const std::string *name = &groupcap.first;
+		const ToolGroupCap *cap = &groupcap.second;
 		os << serializeString(*name);
 		writeS16(os, cap->uses);
 		writeS16(os, cap->maxlevel);
 		writeU32(os, cap->times.size());
-		for (std::unordered_map<int, float>::const_iterator
-				j = cap->times.begin(); j != cap->times.end(); ++j) {
-			writeS16(os, j->first);
-			writeF1000(os, j->second);
+		for (const auto &time : cap->times) {
+			writeS16(os, time.first);
+			writeF1000(os, time.second);
 		}
 	}
 
 	writeU32(os, damageGroups.size());
 
-	for (DamageGroup::const_iterator i = damageGroups.begin();
-			i != damageGroups.end(); ++i) {
-		os << serializeString(i->first);
-		writeS16(os, i->second);
+	for (const auto &damageGroup : damageGroups) {
+		os << serializeString(damageGroup.first);
+		writeS16(os, damageGroup.second);
 	}
 }
 
@@ -107,15 +105,14 @@ DigParams getDigParams(const ItemGroupList &groups,
 	bool result_diggable = false;
 	float result_time = 0.0;
 	float result_wear = 0.0;
-	std::string result_main_group = "";
+	std::string result_main_group;
 
 	int level = itemgroup_get(groups, "level");
 	//infostream<<"level="<<level<<std::endl;
-	for (ToolGCMap::const_iterator i = tp->groupcaps.begin();
-		 	i != tp->groupcaps.end(); ++i) {
-		const std::string &name = i->first;
+	for (const auto &groupcap : tp->groupcaps) {
+		const std::string &name = groupcap.first;
 		//infostream<<"group="<<name<<std::endl;
-		const ToolGroupCap &cap = i->second;
+		const ToolGroupCap &cap = groupcap.second;
 		int rating = itemgroup_get(groups, name);
 		float time = 0;
 		bool time_exists = cap.getTime(rating, &time);
@@ -159,14 +156,14 @@ HitParams getHitParams(const ItemGroupList &armor_groups,
 	s16 damage = 0;
 	float full_punch_interval = tp->full_punch_interval;
 
-	for (DamageGroup::const_iterator i = tp->damageGroups.begin();
-			i != tp->damageGroups.end(); ++i) {
-		s16 armor = itemgroup_get(armor_groups, i->first);
-		damage += i->second * rangelim(time_from_last_punch / full_punch_interval, 0.0, 1.0)
+	for (const auto &damageGroup : tp->damageGroups) {
+		s16 armor = itemgroup_get(armor_groups, damageGroup.first);
+		damage += damageGroup.second
+				* rangelim(time_from_last_punch / full_punch_interval, 0.0, 1.0)
 				* armor / 100.0;
 	}
 
-	return HitParams(damage, 0);
+	return {damage, 0};
 }
 
 HitParams getHitParams(const ItemGroupList &armor_groups,
@@ -183,12 +180,13 @@ PunchDamageResult getPunchDamage(
 ){
 	bool do_hit = true;
 	{
-		if(do_hit && punchitem){
-			if(itemgroup_get(armor_groups, "punch_operable") &&
-					(toolcap == NULL || punchitem->name == ""))
+		if (do_hit && punchitem) {
+			if (itemgroup_get(armor_groups, "punch_operable") &&
+					(toolcap == NULL || punchitem->name.empty()))
 				do_hit = false;
 		}
-		if(do_hit){
+
+		if (do_hit) {
 			if(itemgroup_get(armor_groups, "immortal"))
 				do_hit = false;
 		}
diff --git a/src/tool.h b/src/tool.h
index f3362d892..c6bf0ad73 100644
--- a/src/tool.h
+++ b/src/tool.h
@@ -30,7 +30,7 @@ struct ToolGroupCap
 	int maxlevel = 1;
 	int uses = 20;
 
-	ToolGroupCap() {}
+	ToolGroupCap() = default;
 
 	bool getTime(int rating, float *time) const
 	{
@@ -118,7 +118,7 @@ struct PunchDamageResult
 	int damage = 0;
 	int wear = 0;
 
-	PunchDamageResult() {}
+	PunchDamageResult() = default;
 };
 
 struct ItemStack;
diff --git a/src/touchscreengui.cpp b/src/touchscreengui.cpp
index 9a1ef4086..e849b4053 100644
--- a/src/touchscreengui.cpp
+++ b/src/touchscreengui.cpp
@@ -37,8 +37,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 using namespace irr::core;
 
-extern Settings *g_settings;
-
 const char** touchgui_button_imagenames = (const char*[]) {
 	"up_arrow.png",
 	"down_arrow.png",
@@ -356,7 +354,7 @@ void AutoHideButtonBar::step(float dtime)
 
 void AutoHideButtonBar::deactivate()
 {
-	if (m_visible == true) {
+	if (m_visible) {
 		m_starter.guibutton->setVisible(true);
 		m_starter.guibutton->setEnabled(true);
 	}
diff --git a/src/treegen.cpp b/src/treegen.cpp
index 0806f2927..9e11b1a06 100644
--- a/src/treegen.cpp
+++ b/src/treegen.cpp
@@ -93,7 +93,7 @@ void make_tree(MMVManip &vmanip, v3s16 p0,
 		u32 vi = vmanip.m_area.index(pmin + p1);
 		for (s16 x = leaves_a.MinEdge.X; x <= leaves_a.MaxEdge.X; x++) {
 			v3s16 p(x, y, z);
-			if (vmanip.m_area.contains(p + p1) == true &&
+			if (vmanip.m_area.contains(p + p1) &&
 					(vmanip.m_data[vi].getContent() == CONTENT_AIR ||
 					vmanip.m_data[vi].getContent() == CONTENT_IGNORE)) {
 				if (leaves_d[i] == 1) {
@@ -131,10 +131,8 @@ treegen::error spawn_ltree(ServerEnvironment *env, v3s16 p0,
 	// Send a MEET_OTHER event
 	MapEditEvent event;
 	event.type = MEET_OTHER;
-	for (std::map<v3s16, MapBlock*>::iterator
-			i = modified_blocks.begin();
-			i != modified_blocks.end(); ++i)
-		event.modified_blocks.insert(i->first);
+	for (auto &modified_block : modified_blocks)
+		event.modified_blocks.insert(modified_block.first);
 	map->dispatchEvent(&event);
 	return SUCCESS;
 }
@@ -182,7 +180,7 @@ treegen::error make_ltree(MMVManip &vmanip, v3s16 p0,
 	//generate axiom
 	std::string axiom = tree_definition.initial_axiom;
 	for (s16 i = 0; i < iterations; i++) {
-		std::string temp = "";
+		std::string temp;
 		for (s16 j = 0; j < (s16)axiom.size(); j++) {
 			char axiom_char = axiom.at(j);
 			switch (axiom_char) {
@@ -403,7 +401,7 @@ treegen::error make_ltree(MMVManip &vmanip, v3s16 p0,
 					v3f(position.X, position.Y, position.Z - 1),
 					tree_definition
 				);
-			} if (stack_orientation.empty() == false) {
+			} if (!stack_orientation.empty()) {
 				s16 size = 1;
 				for (x = -size; x <= size; x++)
 				for (y = -size; y <= size; y++)
@@ -527,7 +525,7 @@ treegen::error make_ltree(MMVManip &vmanip, v3s16 p0,
 void tree_node_placement(MMVManip &vmanip, v3f p0, MapNode node)
 {
 	v3s16 p1 = v3s16(myround(p0.X), myround(p0.Y), myround(p0.Z));
-	if (vmanip.m_area.contains(p1) == false)
+	if (!vmanip.m_area.contains(p1))
 		return;
 	u32 vi = vmanip.m_area.index(p1);
 	if (vmanip.m_data[vi].getContent() != CONTENT_AIR
@@ -540,7 +538,7 @@ void tree_node_placement(MMVManip &vmanip, v3f p0, MapNode node)
 void tree_trunk_placement(MMVManip &vmanip, v3f p0, TreeDef &tree_definition)
 {
 	v3s16 p1 = v3s16(myround(p0.X), myround(p0.Y), myround(p0.Z));
-	if (vmanip.m_area.contains(p1) == false)
+	if (!vmanip.m_area.contains(p1))
 		return;
 	u32 vi = vmanip.m_area.index(p1);
 	content_t current_node = vmanip.m_data[vi].getContent();
@@ -560,7 +558,7 @@ void tree_leaves_placement(MMVManip &vmanip, v3f p0,
 	if (ps.range(1, 100) > 100 - tree_definition.leaves2_chance)
 		leavesnode = tree_definition.leaves2node;
 	v3s16 p1 = v3s16(myround(p0.X), myround(p0.Y), myround(p0.Z));
-	if (vmanip.m_area.contains(p1) == false)
+	if (!vmanip.m_area.contains(p1))
 		return;
 	u32 vi = vmanip.m_area.index(p1);
 	if (vmanip.m_data[vi].getContent() != CONTENT_AIR
@@ -584,7 +582,7 @@ void tree_single_leaves_placement(MMVManip &vmanip, v3f p0,
 	if (ps.range(1, 100) > 100 - tree_definition.leaves2_chance)
 		leavesnode = tree_definition.leaves2node;
 	v3s16 p1 = v3s16(myround(p0.X), myround(p0.Y), myround(p0.Z));
-	if (vmanip.m_area.contains(p1) == false)
+	if (!vmanip.m_area.contains(p1))
 		return;
 	u32 vi = vmanip.m_area.index(p1);
 	if (vmanip.m_data[vi].getContent() != CONTENT_AIR
@@ -597,7 +595,7 @@ void tree_single_leaves_placement(MMVManip &vmanip, v3f p0,
 void tree_fruit_placement(MMVManip &vmanip, v3f p0, TreeDef &tree_definition)
 {
 	v3s16 p1 = v3s16(myround(p0.X), myround(p0.Y), myround(p0.Z));
-	if (vmanip.m_area.contains(p1) == false)
+	if (!vmanip.m_area.contains(p1))
 		return;
 	u32 vi = vmanip.m_area.index(p1);
 	if (vmanip.m_data[vi].getContent() != CONTENT_AIR
@@ -734,7 +732,7 @@ void make_jungletree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, s32 seed
 		u32 vi = vmanip.m_area.index(pmin + p1);
 		for (s16 x = leaves_a.MinEdge.X; x <= leaves_a.MaxEdge.X; x++) {
 			v3s16 p(x, y, z);
-			if (vmanip.m_area.contains(p + p1) == true &&
+			if (vmanip.m_area.contains(p + p1) &&
 					(vmanip.m_data[vi].getContent() == CONTENT_AIR ||
 					vmanip.m_data[vi].getContent() == CONTENT_IGNORE)) {
 				if (leaves_d[i] == 1)
@@ -856,7 +854,7 @@ void make_pine_tree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, s32 seed)
 		u32 vi = vmanip.m_area.index(pmin + p1);
 		for (s16 x = leaves_a.MinEdge.X; x <= leaves_a.MaxEdge.X; x++) {
 			v3s16 p(x, y, z);
-			if (vmanip.m_area.contains(p + p1) == true &&
+			if (vmanip.m_area.contains(p + p1) &&
 					(vmanip.m_data[vi].getContent() == CONTENT_AIR ||
 					vmanip.m_data[vi].getContent() == CONTENT_IGNORE ||
 					vmanip.m_data[vi] == snownode)) {
diff --git a/src/unittest/test.cpp b/src/unittest/test.cpp
index b52189cb4..615ec2162 100644
--- a/src/unittest/test.cpp
+++ b/src/unittest/test.cpp
@@ -120,8 +120,8 @@ void TestGameDef::defineSomeNodes()
 		"{default_stone.png";
 	f = ContentFeatures();
 	f.name = itemdef.name;
-	for(int i = 0; i < 6; i++)
-		f.tiledef[i].name = "default_stone.png";
+	for (TileDef &tiledef : f.tiledef)
+		tiledef.name = "default_stone.png";
 	f.is_ground_content = true;
 	idef->registerItem(itemdef);
 	t_CONTENT_STONE = ndef->set(f.name, f);
@@ -175,8 +175,8 @@ void TestGameDef::defineSomeNodes()
 	f.liquid_viscosity = 4;
 	f.is_ground_content = true;
 	f.groups["liquids"] = 3;
-	for(int i = 0; i < 6; i++)
-		f.tiledef[i].name = "default_water.png";
+	for (TileDef &tiledef : f.tiledef)
+		tiledef.name = "default_water.png";
 	idef->registerItem(itemdef);
 	t_CONTENT_WATER = ndef->set(f.name, f);
 
@@ -197,8 +197,8 @@ void TestGameDef::defineSomeNodes()
 	f.light_source = LIGHT_MAX-1;
 	f.is_ground_content = true;
 	f.groups["liquids"] = 3;
-	for(int i = 0; i < 6; i++)
-		f.tiledef[i].name = "default_lava.png";
+	for (TileDef &tiledef : f.tiledef)
+		tiledef.name = "default_lava.png";
 	idef->registerItem(itemdef);
 	t_CONTENT_LAVA = ndef->set(f.name, f);
 
@@ -215,8 +215,8 @@ void TestGameDef::defineSomeNodes()
 		"{default_brick.png";
 	f = ContentFeatures();
 	f.name = itemdef.name;
-	for(int i = 0; i < 6; i++)
-		f.tiledef[i].name = "default_brick.png";
+	for (TileDef &tiledef : f.tiledef)
+		tiledef.name = "default_brick.png";
 	f.is_ground_content = true;
 	idef->registerItem(itemdef);
 	t_CONTENT_BRICK = ndef->set(f.name, f);
diff --git a/src/unittest/test.h b/src/unittest/test.h
index 44b0cd02b..1102f6d33 100644
--- a/src/unittest/test.h
+++ b/src/unittest/test.h
@@ -71,7 +71,7 @@ class TestFailedException : public std::exception {
 	}
 
 // Asserts the comparison specified by CMP is true, or fails the current unit test
-#define UASSERTCMP(T, CMP, actual, expected) do {                         \
+#define UASSERTCMP(T, CMP, actual, expected) {                            \
 	T a = (actual);                                                       \
 	T e = (expected);                                                     \
 	if (!(a CMP e)) {                                                     \
@@ -84,12 +84,12 @@ class TestFailedException : public std::exception {
 			<< e << std::endl;                                            \
 		throw TestFailedException();                                      \
 	}                                                                     \
-} while (0)
+}
 
 #define UASSERTEQ(T, actual, expected) UASSERTCMP(T, ==, actual, expected)
 
 // UASSERTs that the specified exception occurs
-#define EXCEPTION_CHECK(EType, code) do { \
+#define EXCEPTION_CHECK(EType, code) {    \
 	bool exception_thrown = false;        \
 	try {                                 \
 		code;                             \
@@ -97,7 +97,7 @@ class TestFailedException : public std::exception {
 		exception_thrown = true;          \
 	}                                     \
 	UASSERT(exception_thrown);            \
-} while (0)
+}
 
 class IGameDef;
 
diff --git a/src/unittest/test_compression.cpp b/src/unittest/test_compression.cpp
index a3132aa17..7d0378131 100644
--- a/src/unittest/test_compression.cpp
+++ b/src/unittest/test_compression.cpp
@@ -65,8 +65,8 @@ void TestCompression::testRLECompression()
 
 	infostream << "str_out.size()="<<str_out.size()<<std::endl;
 	infostream << "TestCompress: 1,5,5,1 -> ";
-	for (u32 i = 0; i < str_out.size(); i++)
-		infostream << (u32)str_out[i] << ",";
+	for (char i : str_out)
+		infostream << (u32) i << ",";
 	infostream << std::endl;
 
 	UASSERT(str_out.size() == 10);
@@ -89,8 +89,8 @@ void TestCompression::testRLECompression()
 	std::string str_out2 = os2.str();
 
 	infostream << "decompress: ";
-	for (u32 i = 0; i < str_out2.size(); i++)
-		infostream << (u32)str_out2[i] << ",";
+	for (char i : str_out2)
+		infostream << (u32) i << ",";
 	infostream << std::endl;
 
 	UASSERTEQ(size_t, str_out2.size(), fromdata.getSize());
@@ -114,8 +114,8 @@ void TestCompression::testZlibCompression()
 
 	infostream << "str_out.size()=" << str_out.size() <<std::endl;
 	infostream << "TestCompress: 1,5,5,1 -> ";
-	for (u32 i = 0; i < str_out.size(); i++)
-		infostream << (u32)str_out[i] << ",";
+	for (char i : str_out)
+		infostream << (u32) i << ",";
 	infostream << std::endl;
 
 	std::istringstream is(str_out, std::ios_base::binary);
@@ -125,8 +125,8 @@ void TestCompression::testZlibCompression()
 	std::string str_out2 = os2.str();
 
 	infostream << "decompress: ";
-	for (u32 i = 0; i < str_out2.size(); i++)
-		infostream << (u32)str_out2[i] << ",";
+	for (char i : str_out2)
+		infostream << (u32) i << ",";
 	infostream << std::endl;
 
 	UASSERTEQ(size_t, str_out2.size(), fromdata.getSize());
diff --git a/src/unittest/test_nodedef.cpp b/src/unittest/test_nodedef.cpp
index cb99ae854..66ca0ccbc 100644
--- a/src/unittest/test_nodedef.cpp
+++ b/src/unittest/test_nodedef.cpp
@@ -50,8 +50,8 @@ void TestNodeDef::testContentFeaturesSerialization()
 	ContentFeatures f;
 
 	f.name = "default:stone";
-	for (int i = 0; i < 6; i++)
-		f.tiledef[i].name = "default_stone.png";
+	for (TileDef &tiledef : f.tiledef)
+		tiledef.name = "default_stone.png";
 	f.is_ground_content = true;
 
 	std::ostringstream os(std::ios::binary);
diff --git a/src/unittest/test_noise.cpp b/src/unittest/test_noise.cpp
index d1821c950..988ea4495 100644
--- a/src/unittest/test_noise.cpp
+++ b/src/unittest/test_noise.cpp
@@ -113,7 +113,7 @@ void TestNoise::testNoiseInvalidParams()
 		NoiseParams np_highmem(4, 70, v3f(1, 1, 1), 5, 60, 0.7, 10.0);
 		Noise noise_highmem_3d(&np_highmem, 1337, 200, 200, 200);
 		noise_highmem_3d.perlinMap3D(0, 0, 0, NULL);
-	} catch (InvalidNoiseParamsException) {
+	} catch (InvalidNoiseParamsException &) {
 		exception_thrown = true;
 	}
 
diff --git a/src/unittest/test_voxelalgorithms.cpp b/src/unittest/test_voxelalgorithms.cpp
index fd83844af..8c236b73e 100644
--- a/src/unittest/test_voxelalgorithms.cpp
+++ b/src/unittest/test_voxelalgorithms.cpp
@@ -215,11 +215,11 @@ void TestVoxelAlgorithms::testVoxelLineIterator(INodeDefManager *ndef)
 	for (f32 x = -9.1; x < 9; x += 3.124) {
 	for (f32 y = -9.2; y < 9; y += 3.123) {
 	for (f32 z = -9.3; z < 9; z += 3.122) {
-		lines.push_back(core::line3d<f32>(-x, -y, -z, x, y, z));
+		lines.emplace_back(-x, -y, -z, x, y, z);
 	}
 	}
 	}
-	lines.push_back(core::line3d<f32>(0, 0, 0, 0, 0, 0));
+	lines.emplace_back(0, 0, 0, 0, 0, 0);
 	// Test every line
 	std::vector<core::line3d<f32> >::iterator it = lines.begin();
 	for (; it < lines.end(); it++) {
diff --git a/src/util/areastore.cpp b/src/util/areastore.cpp
index c660502f6..50d237bba 100644
--- a/src/util/areastore.cpp
+++ b/src/util/areastore.cpp
@@ -68,9 +68,8 @@ void AreaStore::serialize(std::ostream &os) const
 
 	// TODO: Compression?
 	writeU16(os, areas_map.size());
-	for (AreaMap::const_iterator it = areas_map.begin();
-			it != areas_map.end(); ++it) {
-		const Area &a = it->second;
+	for (const auto &it : areas_map) {
+		const Area &a = it.second;
 		writeV3S16(os, a.minedge);
 		writeV3S16(os, a.maxedge);
 		writeU16(os, a.data.size());
@@ -193,10 +192,9 @@ bool VectorAreaStore::removeArea(u32 id)
 
 void VectorAreaStore::getAreasForPosImpl(std::vector<Area *> *result, v3s16 pos)
 {
-	for (size_t i = 0; i < m_areas.size(); ++i) {
-		Area *b = m_areas[i];
-		if (AST_CONTAINS_PT(b, pos)) {
-			result->push_back(b);
+	for (Area *area : m_areas) {
+		if (AST_CONTAINS_PT(area, pos)) {
+			result->push_back(area);
 		}
 	}
 }
@@ -204,11 +202,10 @@ void VectorAreaStore::getAreasForPosImpl(std::vector<Area *> *result, v3s16 pos)
 void VectorAreaStore::getAreasInArea(std::vector<Area *> *result,
 		v3s16 minedge, v3s16 maxedge, bool accept_overlap)
 {
-	for (size_t i = 0; i < m_areas.size(); ++i) {
-		Area *b = m_areas[i];
-		if (accept_overlap ? AST_AREAS_OVERLAP(minedge, maxedge, b) :
-				AST_CONTAINS_AREA(minedge, maxedge, b)) {
-			result->push_back(b);
+	for (Area *area : m_areas) {
+		if (accept_overlap ? AST_AREAS_OVERLAP(minedge, maxedge, area) :
+				AST_CONTAINS_AREA(minedge, maxedge, area)) {
+			result->push_back(area);
 		}
 	}
 }
diff --git a/src/util/areastore.h b/src/util/areastore.h
index e94aa4e2a..24840210e 100644
--- a/src/util/areastore.h
+++ b/src/util/areastore.h
@@ -37,7 +37,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 
 struct Area {
-	Area() {}
+	Area() = default;
+
 	Area(const v3s16 &mine, const v3s16 &maxe) :
 		minedge(mine), maxedge(maxe)
 	{
@@ -56,7 +57,7 @@ public:
 		m_res_cache(1000, &cacheMiss, this)
 	{}
 
-	virtual ~AreaStore() {}
+	virtual ~AreaStore() = default;
 
 	static AreaStore *getOptimalImplementation();
 
diff --git a/src/util/enriched_string.cpp b/src/util/enriched_string.cpp
index 05d7b8c25..f79e77d5a 100644
--- a/src/util/enriched_string.cpp
+++ b/src/util/enriched_string.cpp
@@ -97,7 +97,6 @@ void EnrichedString::addAtEnd(const std::wstring &s, const SColor &initial_color
 			parseColorString(wide_to_utf8(parts[1]), m_background, true);
 			m_has_background = true;
 		}
-		continue;
 	}
 }
 
@@ -111,7 +110,7 @@ void EnrichedString::addCharNoColor(wchar_t c)
 {
 	m_string += c;
 	if (m_colors.empty()) {
-		m_colors.push_back(SColor(255, 255, 255, 255));
+		m_colors.emplace_back(255, 255, 255, 255);
 	} else {
 		m_colors.push_back(m_colors[m_colors.size() - 1]);
 	}
@@ -138,15 +137,16 @@ EnrichedString EnrichedString::substr(size_t pos, size_t len) const
 	}
 	if (len == std::string::npos || pos + len > m_string.length()) {
 		return EnrichedString(
-		           m_string.substr(pos, std::string::npos),
-		           std::vector<SColor>(m_colors.begin() + pos, m_colors.end())
-		       );
-	} else {
-		return EnrichedString(
-		           m_string.substr(pos, len),
-		           std::vector<SColor>(m_colors.begin() + pos, m_colors.begin() + pos + len)
-		       );
+			m_string.substr(pos, std::string::npos),
+			std::vector<SColor>(m_colors.begin() + pos, m_colors.end())
+		);
 	}
+
+	return EnrichedString(
+		m_string.substr(pos, len),
+		std::vector<SColor>(m_colors.begin() + pos, m_colors.begin() + pos + len)
+	);
+
 }
 
 const wchar_t *EnrichedString::c_str() const
diff --git a/src/util/numeric.h b/src/util/numeric.h
index 36e6fddd0..766efd366 100644
--- a/src/util/numeric.h
+++ b/src/util/numeric.h
@@ -281,7 +281,8 @@ inline aabb3f getNodeBox(v3s16 p, float d)
 class IntervalLimiter
 {
 public:
-	IntervalLimiter() {}
+	IntervalLimiter() = default;
+
 	/*
 		dtime: time from last call to this method
 		wanted_interval: interval wanted
diff --git a/src/util/srp.cpp b/src/util/srp.cpp
index aa8dcb4a7..4c1a772e2 100644
--- a/src/util/srp.cpp
+++ b/src/util/srp.cpp
@@ -697,7 +697,7 @@ struct SRPVerifier *srp_verifier_new(SRP_HashAlgorithm alg,
 		goto cleanup_and_exit;
 	}
 
-	memcpy((char *)ver->username, username, ulen);
+	memcpy(ver->username, username, ulen);
 
 	ver->authenticated = 0;
 
diff --git a/src/util/string.cpp b/src/util/string.cpp
index d41b91f24..fc2a2057f 100644
--- a/src/util/string.cpp
+++ b/src/util/string.cpp
@@ -167,7 +167,7 @@ std::string wide_to_utf8(const std::wstring &input)
 
 wchar_t *utf8_to_wide_c(const char *str)
 {
-	std::wstring ret = utf8_to_wide(std::string(str)).c_str();
+	std::wstring ret = utf8_to_wide(std::string(str));
 	size_t len = ret.length();
 	wchar_t *ret_c = new wchar_t[len + 1];
 	memset(ret_c, 0, (len + 1) * sizeof(wchar_t));
@@ -308,8 +308,8 @@ std::string wide_to_narrow(const std::wstring &wcs)
 	size_t len = wcstombs(*mbs, wcs.c_str(), mbl);
 	if (len == (size_t)(-1))
 		return "Character conversion failed!";
-	else
-		mbs[len] = 0;
+
+	mbs[len] = 0;
 	return *mbs;
 }
 
@@ -321,8 +321,7 @@ std::string urlencode(const std::string &str)
 	// followed by two hex digits. See RFC 3986, section 2.3.
 	static const char url_hex_chars[] = "0123456789ABCDEF";
 	std::ostringstream oss(std::ios::binary);
-	for (u32 i = 0; i < str.size(); i++) {
-		unsigned char c = str[i];
+	for (unsigned char c : str) {
 		if (isalnum(c) || c == '-' || c == '.' || c == '_' || c == '~') {
 			oss << c;
 		} else {
diff --git a/src/util/string.h b/src/util/string.h
index 584ffb73a..122262af8 100644
--- a/src/util/string.h
+++ b/src/util/string.h
@@ -20,7 +20,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #pragma once
 
 #include "irrlichttypes_bloated.h"
-#include <stdlib.h>
+#include <cstdlib>
 #include <string>
 #include <cstring>
 #include <vector>
@@ -231,12 +231,12 @@ inline std::vector<std::basic_string<T> > str_split(
  */
 inline std::string lowercase(const std::string &str)
 {
-	std::string s2 = "";
+	std::string s2;
 
 	s2.reserve(str.size());
 
-	for (size_t i = 0; i < str.size(); i++)
-		s2 += tolower(str[i]);
+	for (char i : str)
+		s2 += tolower(i);
 
 	return s2;
 }
@@ -607,8 +607,8 @@ std::vector<std::basic_string<T> > split(const std::basic_string<T> &s, T delim)
  */
 inline bool is_number(const std::string &to_check)
 {
-	for (size_t i = 0; i < to_check.size(); i++)
-		if (!std::isdigit(to_check[i]))
+	for (char i : to_check)
+		if (!std::isdigit(i))
 			return false;
 
 	return !to_check.empty();
diff --git a/src/voxel.cpp b/src/voxel.cpp
index 981bc5823..cd638183c 100644
--- a/src/voxel.cpp
+++ b/src/voxel.cpp
@@ -21,8 +21,9 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "map.h"
 #include "gettime.h"
 #include "nodedef.h"
+#include "util/directiontables.h"
 #include "util/timetaker.h"
-#include <string.h>  // memcpy, memset
+#include <cstring>  // memcpy, memset
 
 /*
 	Debug stuff
@@ -32,11 +33,6 @@ u64 emerge_time = 0;
 u64 emerge_load_time = 0;
 u64 clearflag_time = 0;
 
-
-VoxelManipulator::VoxelManipulator()
-{
-}
-
 VoxelManipulator::~VoxelManipulator()
 {
 	clear();
@@ -110,7 +106,7 @@ void VoxelManipulator::print(std::ostream &o, INodeDefManager *ndef,
 					{
 						if(ndef->get(m).light_source != 0)
 							c = 'S';
-						else if(ndef->get(m).light_propagates == false)
+						else if(!ndef->get(m).light_propagates)
 							c = 'X';
 						else
 						{
@@ -322,23 +318,13 @@ void VoxelManipulator::clearFlag(u8 flags)
 void VoxelManipulator::unspreadLight(enum LightBank bank, v3s16 p, u8 oldlight,
 		std::set<v3s16> & light_sources, INodeDefManager *nodemgr)
 {
-	v3s16 dirs[6] = {
-		v3s16(0,0,1), // back
-		v3s16(0,1,0), // top
-		v3s16(1,0,0), // right
-		v3s16(0,0,-1), // front
-		v3s16(0,-1,0), // bottom
-		v3s16(-1,0,0), // left
-	};
-
 	VoxelArea voxel_area(p - v3s16(1,1,1), p + v3s16(1,1,1));
 	addArea(voxel_area);
 
 	// Loop through 6 neighbors
-	for(u16 i=0; i<6; i++)
-	{
+	for (const v3s16 &dir : g_6dirs) {
 		// Get the position of the neighbor node
-		v3s16 n2pos = p + dirs[i];
+		v3s16 n2pos = p + dir;
 
 		u32 n2i = m_area.index(n2pos);
 
@@ -387,15 +373,6 @@ void VoxelManipulator::unspreadLight(enum LightBank bank, v3s16 p, u8 oldlight,
 void VoxelManipulator::spreadLight(enum LightBank bank, v3s16 p,
 		INodeDefManager *nodemgr)
 {
-	const v3s16 dirs[6] = {
-		v3s16(0,0,1), // back
-		v3s16(0,1,0), // top
-		v3s16(1,0,0), // right
-		v3s16(0,0,-1), // front
-		v3s16(0,-1,0), // bottom
-		v3s16(-1,0,0), // left
-	};
-
 	VoxelArea voxel_area(p - v3s16(1,1,1), p + v3s16(1,1,1));
 	addArea(voxel_area);
 
@@ -410,10 +387,9 @@ void VoxelManipulator::spreadLight(enum LightBank bank, v3s16 p,
 	u8 newlight = diminish_light(oldlight);
 
 	// Loop through 6 neighbors
-	for(u16 i=0; i<6; i++)
-	{
+	for (const auto &dir : g_6dirs) {
 		// Get the position of the neighbor node
-		v3s16 n2pos = p + dirs[i];
+		v3s16 n2pos = p + dir;
 
 		u32 n2i = m_area.index(n2pos);
 
@@ -457,25 +433,12 @@ const MapNode VoxelManipulator::ContentIgnoreNode = MapNode(CONTENT_IGNORE);
 void VoxelManipulator::spreadLight(enum LightBank bank,
 		std::set<v3s16> & from_nodes, INodeDefManager *nodemgr)
 {
-	const v3s16 dirs[6] = {
-		v3s16(0,0,1), // back
-		v3s16(0,1,0), // top
-		v3s16(1,0,0), // right
-		v3s16(0,0,-1), // front
-		v3s16(0,-1,0), // bottom
-		v3s16(-1,0,0), // left
-	};
-
 	if(from_nodes.empty())
 		return;
 
 	std::set<v3s16> lighted_nodes;
 
-	for(std::set<v3s16>::iterator j = from_nodes.begin();
-		j != from_nodes.end(); ++j)
-	{
-		v3s16 pos = *j;
-
+	for (const v3s16 &pos : from_nodes) {
 		VoxelArea voxel_area(pos - v3s16(1,1,1), pos + v3s16(1,1,1));
 		addArea(voxel_area);
 
@@ -490,10 +453,9 @@ void VoxelManipulator::spreadLight(enum LightBank bank,
 		u8 newlight = diminish_light(oldlight);
 
 		// Loop through 6 neighbors
-		for(u16 i=0; i<6; i++)
-		{
+		for (const v3s16 &dir : g_6dirs) {
 			// Get the position of the neighbor node
-			v3s16 n2pos = pos + dirs[i];
+			v3s16 n2pos = pos + dir;
 
 			try
 			{
diff --git a/src/voxel.h b/src/voxel.h
index 49a75c95f..d03cecd95 100644
--- a/src/voxel.h
+++ b/src/voxel.h
@@ -59,7 +59,7 @@ class VoxelArea
 {
 public:
 	// Starts as zero sized
-	VoxelArea() {}
+	VoxelArea() = default;
 
 	VoxelArea(const v3s16 &min_edge, const v3s16 &max_edge):
 		MinEdge(min_edge),
@@ -175,12 +175,12 @@ public:
 
 	VoxelArea operator+(const v3s16 &off) const
 	{
-		return VoxelArea(MinEdge+off, MaxEdge+off);
+		return {MinEdge+off, MaxEdge+off};
 	}
 
 	VoxelArea operator-(const v3s16 &off) const
 	{
-		return VoxelArea(MinEdge-off, MaxEdge-off);
+		return {MinEdge-off, MaxEdge-off};
 	}
 
 	/*
@@ -344,7 +344,7 @@ enum VoxelPrintMode
 class VoxelManipulator
 {
 public:
-	VoxelManipulator();
+	VoxelManipulator() = default;
 	virtual ~VoxelManipulator();
 
 	/*
@@ -374,7 +374,7 @@ public:
 		addArea(voxel_area);
 
 		if (m_flags[m_area.index(p)] & VOXELFLAG_NO_DATA) {
-			return MapNode(CONTENT_IGNORE);
+			return {CONTENT_IGNORE};
 		}
 
 		return m_data[m_area.index(p)];
@@ -382,9 +382,9 @@ public:
 	MapNode getNodeNoExNoEmerge(const v3s16 &p)
 	{
 		if (!m_area.contains(p))
-			return MapNode(CONTENT_IGNORE);
+			return {CONTENT_IGNORE};
 		if (m_flags[m_area.index(p)] & VOXELFLAG_NO_DATA)
-			return MapNode(CONTENT_IGNORE);
+			return {CONTENT_IGNORE};
 		return m_data[m_area.index(p)];
 	}
 	// Stuff explodes if non-emerged area is touched with this.
diff --git a/src/voxelalgorithms.cpp b/src/voxelalgorithms.cpp
index 74c165dd3..250a57cb2 100644
--- a/src/voxelalgorithms.cpp
+++ b/src/voxelalgorithms.cpp
@@ -118,7 +118,7 @@ SunlightPropagateResult propagateSunlight(VoxelManipulator &v, VoxelArea a,
 			} else if(incoming_light == LIGHT_SUN &&
 					ndef->get(n).sunlight_propagates){
 				// Do nothing
-			} else if(ndef->get(n).sunlight_propagates == false){
+			} else if(!ndef->get(n).sunlight_propagates){
 				incoming_light = 0;
 			} else {
 				incoming_light = diminish_light(incoming_light);
@@ -152,7 +152,7 @@ SunlightPropagateResult propagateSunlight(VoxelManipulator &v, VoxelArea a,
 		}
 	}
 
-	return SunlightPropagateResult(bottom_sunlight_valid);
+	return {bottom_sunlight_valid};
 }
 
 /*!
@@ -186,21 +186,16 @@ struct ChangingLight {
 	//! Position of the node's block.
 	mapblock_v3 block_position;
 	//! Pointer to the node's block.
-	MapBlock *block;
+	MapBlock *block = NULL;
 	/*!
 	 * Direction from the node that caused this node's changing
 	 * to this node.
 	 */
-	direction source_direction;
+	direction source_direction = 6;
 
-	ChangingLight() :
-		rel_position(),
-		block_position(),
-		block(NULL),
-		source_direction(6)
-	{}
+	ChangingLight() = default;
 
-	ChangingLight(relative_v3 rel_pos, mapblock_v3 block_pos,
+	ChangingLight(const relative_v3 &rel_pos, const mapblock_v3 &block_pos,
 		MapBlock *b, direction source_dir) :
 		rel_position(rel_pos),
 		block_position(block_pos),
@@ -265,8 +260,7 @@ struct LightQueue {
 		direction source_dir)
 	{
 		assert(light <= LIGHT_SUN);
-		lights[light].push_back(
-			ChangingLight(rel_pos, block_pos, block, source_dir));
+		lights[light].emplace_back(rel_pos, block_pos, block, source_dir);
 	}
 };
 
@@ -611,8 +605,7 @@ void update_lighting_nodes(Map *map,
 	bool is_valid_position;
 
 	// Process each light bank separately
-	for (s32 i = 0; i < 2; i++) {
-		LightBank bank = banks[i];
+	for (LightBank bank : banks) {
 		UnlightQueue disappearing_lights(256);
 		ReLightQueue light_sources(256);
 		// Nodes that are brighter than the brightest modified node was
@@ -663,8 +656,8 @@ void update_lighting_nodes(Map *map,
 					new_light = LIGHT_SUN;
 				} else {
 					new_light = ndef->get(n).light_source;
-					for (int i = 0; i < 6; i++) {
-						v3s16 p2 = p + neighbor_dirs[i];
+					for (const v3s16 &neighbor_dir : neighbor_dirs) {
+						v3s16 p2 = p + neighbor_dir;
 						bool is_valid;
 						MapNode n2 = map->getNodeNoEx(p2, &is_valid);
 						if (is_valid) {
@@ -813,8 +806,8 @@ bool is_light_locally_correct(Map *map, INodeDefManager *ndef, LightBank bank,
 	u8 light = n.getLightNoChecks(bank, &f);
 	assert(f.light_source <= LIGHT_MAX);
 	u8 brightest_neighbor = f.light_source + 1;
-	for (direction d = 0; d < 6; ++d) {
-		MapNode n2 = map->getNodeNoEx(pos + neighbor_dirs[d],
+	for (const v3s16 &neighbor_dir : neighbor_dirs) {
+		MapNode n2 = map->getNodeNoEx(pos + neighbor_dir,
 			&is_valid_position);
 		u8 light2 = n2.getLight(bank, ndef);
 		if (brightest_neighbor < light2) {
@@ -830,8 +823,7 @@ void update_block_border_lighting(Map *map, MapBlock *block,
 {
 	INodeDefManager *ndef = map->getNodeDefManager();
 	bool is_valid_position;
-	for (s32 i = 0; i < 2; i++) {
-		LightBank bank = banks[i];
+	for (LightBank bank : banks) {
 		// Since invalid light is not common, do not allocate
 		// memory if not needed.
 		UnlightQueue disappearing_lights(0);
@@ -1213,8 +1205,7 @@ void blit_back_with_light(ServerMap *map, MMVManip *vm,
 		data.target_block = v3s16(x, minblock.Y - 1, z);
 		for (s16 z = 0; z < MAP_BLOCKSIZE; z++)
 		for (s16 x = 0; x < MAP_BLOCKSIZE; x++)
-			data.data.push_back(
-				SunlightPropagationUnit(v2s16(x, z), lights[z][x]));
+			data.data.emplace_back(v2s16(x, z), lights[z][x]);
 		// Propagate sunlight and shadow below the voxel manipulator.
 		while (!data.data.empty()) {
 			if (propagate_block_sunlight(map, ndef, &data, &unlight[0],
@@ -1241,8 +1232,7 @@ void blit_back_with_light(ServerMap *map, MMVManip *vm,
 			continue;
 		v3s16 offset = block->getPosRelative();
 		// For each border of the block:
-		for (direction d = 0; d < 6; d++) {
-			VoxelArea a = block_pad[d];
+		for (const VoxelArea &a : block_pad) {
 			// For each node of the border:
 			for (s32 x = a.MinEdge.X; x <= a.MaxEdge.X; x++)
 			for (s32 z = a.MinEdge.Z; z <= a.MaxEdge.Z; z++)
@@ -1353,8 +1343,7 @@ void repair_block_light(ServerMap *map, MapBlock *block,
 	data.target_block = v3s16(blockpos.X, blockpos.Y - 1, blockpos.Z);
 	for (s16 z = 0; z < MAP_BLOCKSIZE; z++)
 	for (s16 x = 0; x < MAP_BLOCKSIZE; x++) {
-		data.data.push_back(
-			SunlightPropagationUnit(v2s16(x, z), lights[z][x]));
+		data.data.emplace_back(v2s16(x, z), lights[z][x]);
 	}
 	// Propagate sunlight and shadow below the voxel manipulator.
 	while (!data.data.empty()) {
@@ -1369,8 +1358,7 @@ void repair_block_light(ServerMap *map, MapBlock *block,
 	// --- STEP 2: Get nodes from borders to unlight
 
 	// For each border of the block:
-	for (direction d = 0; d < 6; d++) {
-		VoxelArea a = block_pad[d];
+	for (const VoxelArea &a : block_pad) {
 		// For each node of the border:
 		for (s32 x = a.MinEdge.X; x <= a.MaxEdge.X; x++)
 		for (s32 z = a.MinEdge.Z; z <= a.MaxEdge.Z; z++)
diff --git a/src/wieldmesh.cpp b/src/wieldmesh.cpp
index dbec4a177..332c8ba22 100644
--- a/src/wieldmesh.cpp
+++ b/src/wieldmesh.cpp
@@ -146,10 +146,8 @@ public:
 	// Destructor
 	virtual ~ExtrusionMeshCache()
 	{
-		for (std::map<int, scene::IMesh*>::iterator
-				it = m_extrusion_meshes.begin();
-				it != m_extrusion_meshes.end(); ++it) {
-			it->second->drop();
+		for (auto &extrusion_meshe : m_extrusion_meshes) {
+			extrusion_meshe.second->drop();
 		}
 		m_cube->drop();
 	}
@@ -309,14 +307,15 @@ void WieldMeshSceneNode::setItem(const ItemStack &item, Client *client)
 	m_base_color = idef->getItemstackColor(item, client);
 
 	// If wield_image is defined, it overrides everything else
-	if (def.wield_image != "") {
+	if (!def.wield_image.empty()) {
 		setExtruded(def.wield_image, def.wield_scale, tsrc, 1);
-		m_colors.push_back(ItemPartColor());
+		m_colors.emplace_back();
 		return;
 	}
+
 	// Handle nodes
 	// See also CItemDefManager::createClientCached()
-	else if (def.type == ITEM_NODE) {
+	if (def.type == ITEM_NODE) {
 		if (f.mesh_ptr[0]) {
 			// e.g. mesh nodes and nodeboxes
 			scene::SMesh *mesh = cloneMesh(f.mesh_ptr[0]);
@@ -377,9 +376,9 @@ void WieldMeshSceneNode::setItem(const ItemStack &item, Client *client)
 		}
 		return;
 	}
-	else if (def.inventory_image != "") {
+	else if (!def.inventory_image.empty()) {
 		setExtruded(def.inventory_image, def.wield_scale, tsrc, 1);
-		m_colors.push_back(ItemPartColor());
+		m_colors.emplace_back();
 		return;
 	}
 
@@ -455,9 +454,9 @@ void getItemMesh(Client *client, const ItemStack &item, ItemMesh *result)
 	result->needs_shading = true;
 
 	// If inventory_image is defined, it overrides everything else
-	if (def.inventory_image != "") {
+	if (!def.inventory_image.empty()) {
 		mesh = getExtrudedMesh(tsrc, def.inventory_image);
-		result->buffer_colors.push_back(ItemPartColor());
+		result->buffer_colors.emplace_back();
 		// Items with inventory images do not need shading
 		result->needs_shading = false;
 	} else if (def.type == ITEM_NODE) {
@@ -560,7 +559,7 @@ scene::SMesh *getExtrudedMesh(ITextureSource *tsrc, const std::string &imagename
 }
 
 void postProcessNodeMesh(scene::SMesh *mesh, const ContentFeatures &f,
-	bool use_shaders, bool set_material, video::E_MATERIAL_TYPE *mattype,
+	bool use_shaders, bool set_material, const video::E_MATERIAL_TYPE *mattype,
 	std::vector<ItemPartColor> *colors)
 {
 	u32 mc = mesh->getMeshBufferCount();
diff --git a/src/wieldmesh.h b/src/wieldmesh.h
index 51ba20536..828625075 100644
--- a/src/wieldmesh.h
+++ b/src/wieldmesh.h
@@ -44,7 +44,7 @@ struct ItemPartColor
 	 */
 	video::SColor color = 0;
 
-	ItemPartColor() {}
+	ItemPartColor() = default;
 
 	ItemPartColor(bool override, video::SColor color)
 	    : override_base(override), color(color)
@@ -65,7 +65,7 @@ struct ItemMesh
 	 */
 	bool needs_shading = true;
 
-	ItemMesh() {}
+	ItemMesh() = default;
 };
 
 /*
@@ -135,5 +135,5 @@ scene::SMesh *getExtrudedMesh(ITextureSource *tsrc, const std::string &imagename
  * \param colors returns the colors of the mesh buffers in the mesh.
  */
 void postProcessNodeMesh(scene::SMesh *mesh, const ContentFeatures &f, bool use_shaders,
-		bool set_material, video::E_MATERIAL_TYPE *mattype,
+		bool set_material, const video::E_MATERIAL_TYPE *mattype,
 		std::vector<ItemPartColor> *colors);