diff --git a/src/guiscalingfilter.h b/src/guiscalingfilter.h
index 7408ff5eb..4661bf8da 100644
--- a/src/guiscalingfilter.h
+++ b/src/guiscalingfilter.h
@@ -46,5 +46,5 @@ video::ITexture *guiScalingImageButton(video::IVideoDriver *driver, video::IText
  */
 void draw2DImageFilterScaled(video::IVideoDriver *driver, video::ITexture *txr,
 		const core::rect<s32> &destrect, const core::rect<s32> &srcrect,
-		const core::rect<s32> *cliprect = 0, video::SColor *const colors = 0,
+		const core::rect<s32> *cliprect = 0, const video::SColor *const colors = 0,
 		bool usealpha = false);
diff --git a/src/httpfetch.h b/src/httpfetch.h
index 206576849..db43e3a4b 100644
--- a/src/httpfetch.h
+++ b/src/httpfetch.h
@@ -76,7 +76,7 @@ struct HTTPFetchResult
 	unsigned long caller = HTTPFETCH_DISCARD;
 	unsigned long request_id = 0;
 
-	HTTPFetchResult() {}
+	HTTPFetchResult() = default;
 
 	HTTPFetchResult(const HTTPFetchRequest &fetch_request)
 	    : caller(fetch_request.caller), request_id(fetch_request.request_id)
diff --git a/src/hud.cpp b/src/hud.cpp
index 70903ce15..14e784a62 100644
--- a/src/hud.cpp
+++ b/src/hud.cpp
@@ -55,8 +55,8 @@ Hud::Hud(gui::IGUIEnvironment *guienv, Client *client, LocalPlayer *player,
 	m_hotbar_imagesize *= m_hud_scaling;
 	m_padding = m_hotbar_imagesize / 12;
 
-	for (unsigned int i = 0; i < 4; i++)
-		hbar_colors[i] = video::SColor(255, 255, 255, 255);
+	for (auto &hbar_color : hbar_colors)
+		hbar_color = video::SColor(255, 255, 255, 255);
 
 	tsrc = client->getTextureSource();
 
@@ -220,7 +220,7 @@ void Hud::drawItems(v2s32 upperleftpos, v2s32 screen_offset, s32 itemcount,
 	// Store hotbar_image in member variable, used by drawItem()
 	if (hotbar_image != player->hotbar_image) {
 		hotbar_image = player->hotbar_image;
-		if (hotbar_image != "")
+		if (!hotbar_image.empty())
 			use_hotbar_image = tsrc->isKnownSourceImage(hotbar_image);
 		else
 			use_hotbar_image = false;
@@ -229,7 +229,7 @@ void Hud::drawItems(v2s32 upperleftpos, v2s32 screen_offset, s32 itemcount,
 	// Store hotbar_selected_image in member variable, used by drawItem()
 	if (hotbar_selected_image != player->hotbar_selected_image) {
 		hotbar_selected_image = player->hotbar_selected_image;
-		if (hotbar_selected_image != "")
+		if (!hotbar_selected_image.empty())
 			use_hotbar_selected_image = tsrc->isKnownSourceImage(hotbar_selected_image);
 		else
 			use_hotbar_selected_image = false;
@@ -572,7 +572,7 @@ void Hud::updateSelectionMesh(const v3s16 &camera_offset)
 		m_selection_mesh = NULL;
 	}
 
-	if (!m_selection_boxes.size()) {
+	if (m_selection_boxes.empty()) {
 		// No pointed object
 		return;
 	}
@@ -597,10 +597,8 @@ void Hud::updateSelectionMesh(const v3s16 &camera_offset)
 	aabb3f halo_box(100.0, 100.0, 100.0, -100.0, -100.0, -100.0);
 	m_halo_boxes.clear();
 
-	for (std::vector<aabb3f>::iterator
-			i = m_selection_boxes.begin();
-			i != m_selection_boxes.end(); ++i) {
-		halo_box.addInternalBox(*i);
+	for (const auto &selection_box : m_selection_boxes) {
+		halo_box.addInternalBox(selection_box);
 	}
 
 	m_halo_boxes.push_back(halo_box);
diff --git a/src/imagefilters.cpp b/src/imagefilters.cpp
index b34027725..dd029628f 100644
--- a/src/imagefilters.cpp
+++ b/src/imagefilters.cpp
@@ -18,7 +18,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #include "imagefilters.h"
 #include "util/numeric.h"
-#include <math.h>
+#include <cmath>
 
 /* Fill in RGB values for transparent pixels, to correct for odd colors
  * appearing at borders when blending.  This is because many PNG optimizers
diff --git a/src/intlGUIEditBox.cpp b/src/intlGUIEditBox.cpp
index 2aacc7259..671b37c5d 100644
--- a/src/intlGUIEditBox.cpp
+++ b/src/intlGUIEditBox.cpp
@@ -630,8 +630,7 @@ bool intlGUIEditBox::processKey(const SEvent& event)
 		if ( !this->IsEnabled )
 			break;
 
-		if (Text.size())
-		{
+		if (!Text.empty()) {
 			core::stringw s;
 
 			if (MarkBegin != MarkEnd)
@@ -670,8 +669,7 @@ bool intlGUIEditBox::processKey(const SEvent& event)
 		if ( !this->IsEnabled )
 			break;
 
-		if (Text.size() != 0)
-		{
+		if (!Text.empty()) {
 			core::stringw s;
 
 			if (MarkBegin != MarkEnd)
@@ -820,8 +818,7 @@ void intlGUIEditBox::draw()
 		const bool prevOver = OverrideColorEnabled;
 		const video::SColor prevColor = OverrideColor;
 
-		if (Text.size())
-		{
+		if (!Text.empty()) {
 			if (!IsEnabled && !OverrideColorEnabled)
 			{
 				OverrideColorEnabled = true;
@@ -908,7 +905,7 @@ void intlGUIEditBox::draw()
 					// draw marked text
 					s = txtLine->subString(lineStartPos, lineEndPos - lineStartPos);
 
-					if (s.size())
+					if (!s.empty())
 						font->draw(s.c_str(), CurrentTextRect,
 							OverrideColorEnabled ? OverrideColor : skin->getColor(EGDC_HIGH_LIGHT_TEXT),
 							false, true, &localClipRect);
@@ -1057,24 +1054,22 @@ bool intlGUIEditBox::processMouse(const SEvent& event)
 		else
 		{
 			if (!AbsoluteClippingRect.isPointInside(
-				core::position2d<s32>(event.MouseInput.X, event.MouseInput.Y)))
-			{
+				core::position2d<s32>(event.MouseInput.X, event.MouseInput.Y))) {
 				return false;
 			}
-			else
-			{
-				// move cursor
-				CursorPos = getCursorPos(event.MouseInput.X, event.MouseInput.Y);
 
-                s32 newMarkBegin = MarkBegin;
-				if (!MouseMarking)
-					newMarkBegin = CursorPos;
 
-				MouseMarking = true;
-				setTextMarkers( newMarkBegin, CursorPos);
-				calculateScrollPos();
-				return true;
-			}
+			// move cursor
+			CursorPos = getCursorPos(event.MouseInput.X, event.MouseInput.Y);
+
+			s32 newMarkBegin = MarkBegin;
+			if (!MouseMarking)
+				newMarkBegin = CursorPos;
+
+			MouseMarking = true;
+			setTextMarkers( newMarkBegin, CursorPos);
+			calculateScrollPos();
+			return true;
 		}
 	default:
 		break;
@@ -1185,8 +1180,7 @@ void intlGUIEditBox::breakText()
 
 		if (c == L' ' || c == 0 || i == (size-1))
 		{
-			if (word.size())
-			{
+			if (!word.empty()) {
 				// here comes the next whitespace, look if
 				// we can break the last word to the next line.
 				s32 whitelgth = font->getDimension(whitespace.c_str()).Width;
@@ -1488,7 +1482,7 @@ void intlGUIEditBox::deserializeAttributes(io::IAttributes* in, io::SAttributeRe
 	setAutoScroll(in->getAttributeAsBool("AutoScroll"));
 	core::stringw ch = in->getAttributeAsStringW("PasswordChar");
 
-	if (!ch.size())
+	if (ch.empty())
 		setPasswordBox(in->getAttributeAsBool("PasswordBox"));
 	else
 		setPasswordBox(in->getAttributeAsBool("PasswordBox"), ch[0]);
diff --git a/src/inventory.cpp b/src/inventory.cpp
index 4da380a24..82325997e 100644
--- a/src/inventory.cpp
+++ b/src/inventory.cpp
@@ -35,11 +35,9 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 static content_t content_translate_from_19_to_internal(content_t c_from)
 {
-	for(u32 i=0; i<sizeof(trans_table_19)/sizeof(trans_table_19[0]); i++)
-	{
-		if(trans_table_19[i][1] == c_from)
-		{
-			return trans_table_19[i][0];
+	for (const auto &tt : trans_table_19) {
+		if(tt[1] == c_from) {
+			return tt[0];
 		}
 	}
 	return c_from;
@@ -116,7 +114,7 @@ void ItemStack::deSerialize(std::istream &is, IItemDefManager *itemdef)
 		NameIdMapping legacy_nimap;
 		content_mapnode_get_name_id_mapping(&legacy_nimap);
 		legacy_nimap.getName(material, name);
-		if(name == "")
+		if(name.empty())
 			name = "unknown_block";
 		if (itemdef)
 			name = itemdef->getAlias(name);
@@ -136,7 +134,7 @@ void ItemStack::deSerialize(std::istream &is, IItemDefManager *itemdef)
 		NameIdMapping legacy_nimap;
 		content_mapnode_get_name_id_mapping(&legacy_nimap);
 		legacy_nimap.getName(material, name);
-		if(name == "")
+		if(name.empty())
 			name = "unknown_block";
 		if (itemdef)
 			name = itemdef->getAlias(name);
@@ -207,21 +205,20 @@ void ItemStack::deSerialize(std::istream &is, IItemDefManager *itemdef)
 			// Read the count
 			std::string count_str;
 			std::getline(is, count_str, ' ');
-			if(count_str.empty())
-			{
+			if (count_str.empty()) {
 				count = 1;
 				break;
 			}
-			else
-				count = stoi(count_str);
+
+			count = stoi(count_str);
 
 			// Read the wear
 			std::string wear_str;
 			std::getline(is, wear_str, ' ');
 			if(wear_str.empty())
 				break;
-			else
-				wear = stoi(wear_str);
+
+			wear = stoi(wear_str);
 
 			// Read metadata
 			metadata.deSerialize(is);
@@ -388,17 +385,12 @@ InventoryList::InventoryList(const std::string &name, u32 size, IItemDefManager
 	clearItems();
 }
 
-InventoryList::~InventoryList()
-{
-}
-
 void InventoryList::clearItems()
 {
 	m_items.clear();
 
-	for(u32 i=0; i<m_size; i++)
-	{
-		m_items.push_back(ItemStack());
+	for (u32 i=0; i < m_size; i++) {
+		m_items.emplace_back();
 	}
 
 	//setDirty(true);
@@ -427,15 +419,10 @@ void InventoryList::serialize(std::ostream &os) const
 
 	os<<"Width "<<m_width<<"\n";
 
-	for(u32 i=0; i<m_items.size(); i++)
-	{
-		const ItemStack &item = m_items[i];
-		if(item.empty())
-		{
+	for (const auto &item : m_items) {
+		if (item.empty()) {
 			os<<"Empty";
-		}
-		else
-		{
+		} else {
 			os<<"Item ";
 			item.serialize(os);
 		}
@@ -464,17 +451,16 @@ void InventoryList::deSerialize(std::istream &is)
 		std::string name;
 		std::getline(iss, name, ' ');
 
-		if(name == "EndInventoryList")
-		{
+		if (name == "EndInventoryList") {
 			break;
 		}
+
 		// This is a temporary backwards compatibility fix
-		else if(name == "end")
-		{
+		if (name == "end") {
 			break;
 		}
-		else if(name == "Width")
-		{
+
+		if (name == "Width") {
 			iss >> m_width;
 			if (iss.fail())
 				throw SerializationError("incorrect width property");
@@ -551,9 +537,8 @@ u32 InventoryList::getWidth() const
 u32 InventoryList::getUsedSlots() const
 {
 	u32 num = 0;
-	for(u32 i=0; i<m_items.size(); i++)
-	{
-		if(!m_items[i].empty())
+	for (const auto &m_item : m_items) {
+		if (!m_item.empty())
 			num++;
 	}
 	return num;
@@ -672,20 +657,17 @@ bool InventoryList::roomForItem(const ItemStack &item_) const
 bool InventoryList::containsItem(const ItemStack &item, bool match_meta) const
 {
 	u32 count = item.count;
-	if(count == 0)
+	if (count == 0)
 		return true;
-	for(std::vector<ItemStack>::const_reverse_iterator
-			i = m_items.rbegin();
-			i != m_items.rend(); ++i)
-	{
-		if(count == 0)
+
+	for (auto i = m_items.rbegin(); i != m_items.rend(); ++i) {
+		if (count == 0)
 			break;
-		if (i->name == item.name
-				&& (!match_meta || (i->metadata == item.metadata))) {
+		if (i->name == item.name && (!match_meta || (i->metadata == item.metadata))) {
 			if (i->count >= count)
 				return true;
-			else
-				count -= i->count;
+
+			count -= i->count;
 		}
 	}
 	return false;
@@ -694,15 +676,11 @@ bool InventoryList::containsItem(const ItemStack &item, bool match_meta) const
 ItemStack InventoryList::removeItem(const ItemStack &item)
 {
 	ItemStack removed;
-	for(std::vector<ItemStack>::reverse_iterator
-			i = m_items.rbegin();
-			i != m_items.rend(); ++i)
-	{
-		if(i->name == item.name)
-		{
+	for (auto i = m_items.rbegin(); i != m_items.rend(); ++i) {
+		if (i->name == item.name) {
 			u32 still_to_remove = item.count - removed.count;
 			removed.addItem(i->takeItem(still_to_remove), m_itemdef);
-			if(removed.count == item.count)
+			if (removed.count == item.count)
 				break;
 		}
 	}
@@ -815,9 +793,8 @@ Inventory::~Inventory()
 void Inventory::clear()
 {
 	m_dirty = true;
-	for(u32 i=0; i<m_lists.size(); i++)
-	{
-		delete m_lists[i];
+	for (auto &m_list : m_lists) {
+		delete m_list;
 	}
 	m_lists.clear();
 }
@@ -825,11 +802,8 @@ void Inventory::clear()
 void Inventory::clearContents()
 {
 	m_dirty = true;
-	for(u32 i=0; i<m_lists.size(); i++)
-	{
-		InventoryList *list = m_lists[i];
-		for(u32 j=0; j<list->getSize(); j++)
-		{
+	for (InventoryList *list : m_lists) {
+		for (u32 j=0; j<list->getSize(); j++) {
 			list->deleteItem(j);
 		}
 	}
@@ -855,9 +829,8 @@ Inventory & Inventory::operator = (const Inventory &other)
 		m_dirty = true;
 		clear();
 		m_itemdef = other.m_itemdef;
-		for(u32 i=0; i<other.m_lists.size(); i++)
-		{
-			m_lists.push_back(new InventoryList(*other.m_lists[i]));
+		for (InventoryList *list : other.m_lists) {
+			m_lists.push_back(new InventoryList(*list));
 		}
 	}
 	return *this;
@@ -878,9 +851,7 @@ bool Inventory::operator == (const Inventory &other) const
 
 void Inventory::serialize(std::ostream &os) const
 {
-	for(u32 i=0; i<m_lists.size(); i++)
-	{
-		InventoryList *list = m_lists[i];
+	for (InventoryList *list : m_lists) {
 		os<<"List "<<list->getName()<<" "<<list->getSize()<<"\n";
 		list->serialize(os);
 	}
@@ -902,17 +873,16 @@ void Inventory::deSerialize(std::istream &is)
 		std::string name;
 		std::getline(iss, name, ' ');
 
-		if(name == "EndInventory")
-		{
+		if (name == "EndInventory") {
 			break;
 		}
+
 		// This is a temporary backwards compatibility fix
-		else if(name == "end")
-		{
+		if (name == "end") {
 			break;
 		}
-		else if(name == "List")
-		{
+
+		if (name == "List") {
 			std::string listname;
 			u32 listsize;
 
@@ -944,15 +914,14 @@ InventoryList * Inventory::addList(const std::string &name, u32 size)
 		}
 		return m_lists[i];
 	}
-	else
-	{
-		//don't create list with invalid name
-		if (name.find(" ") != std::string::npos) return NULL;
 
-		InventoryList *list = new InventoryList(name, size, m_itemdef);
-		m_lists.push_back(list);
-		return list;
-	}
+
+	//don't create list with invalid name
+	if (name.find(' ') != std::string::npos) return NULL;
+
+	InventoryList *list = new InventoryList(name, size, m_itemdef);
+	m_lists.push_back(list);
+	return list;
 }
 
 InventoryList * Inventory::getList(const std::string &name)
@@ -966,9 +935,7 @@ InventoryList * Inventory::getList(const std::string &name)
 std::vector<const InventoryList*> Inventory::getLists()
 {
 	std::vector<const InventoryList*> lists;
-	for(u32 i=0; i<m_lists.size(); i++)
-	{
-		InventoryList *list = m_lists[i];
+	for (auto list : m_lists) {
 		lists.push_back(list);
 	}
 	return lists;
diff --git a/src/inventory.h b/src/inventory.h
index c11264213..aff0ce20f 100644
--- a/src/inventory.h
+++ b/src/inventory.h
@@ -172,7 +172,7 @@ class InventoryList
 {
 public:
 	InventoryList(const std::string &name, u32 size, IItemDefManager *itemdef);
-	~InventoryList();
+	~InventoryList() = default;
 	void clearItems();
 	void setSize(u32 newsize);
 	void setWidth(u32 newWidth);
diff --git a/src/inventorymanager.cpp b/src/inventorymanager.cpp
index 0d44e9cda..d4315f7a4 100644
--- a/src/inventorymanager.cpp
+++ b/src/inventorymanager.cpp
@@ -774,17 +774,15 @@ void ICraftAction::apply(InventoryManager *mgr,
 
 		// Add the new replacements to the list
 		IItemDefManager *itemdef = gamedef->getItemDefManager();
-		for (std::vector<ItemStack>::iterator it = temp.begin();
-				it != temp.end(); ++it) {
-			for (std::vector<ItemStack>::iterator jt = output_replacements.begin();
-					jt != output_replacements.end(); ++jt) {
-				if (it->name == jt->name) {
-					*it = jt->addItem(*it, itemdef);
-					if (it->empty())
+		for (auto &itemstack : temp) {
+			for (auto &output_replacement : output_replacements) {
+				if (itemstack.name == output_replacement.name) {
+					itemstack = output_replacement.addItem(itemstack, itemdef);
+					if (itemstack.empty())
 						continue;
 				}
 			}
-			output_replacements.push_back(*it);
+			output_replacements.push_back(itemstack);
 		}
 
 		actionstream << player->getDescription()
@@ -795,7 +793,8 @@ void ICraftAction::apply(InventoryManager *mgr,
 		// Decrement counter
 		if (count_remaining == 1)
 			break;
-		else if (count_remaining > 1)
+
+		if (count_remaining > 1)
 			count_remaining--;
 
 		// Get next crafting result
@@ -806,24 +805,23 @@ void ICraftAction::apply(InventoryManager *mgr,
 
 	// Put the replacements in the inventory or drop them on the floor, if
 	// the invenotry is full
-	for (std::vector<ItemStack>::iterator it = output_replacements.begin();
-			it != output_replacements.end(); ++it) {
+	for (auto &output_replacement : output_replacements) {
 		if (list_main)
-			*it = list_main->addItem(*it);
-		if (it->empty())
+			output_replacement = list_main->addItem(output_replacement);
+		if (output_replacement.empty())
 			continue;
-		u16 count = it->count;
+		u16 count = output_replacement.count;
 		do {
-			PLAYER_TO_SA(player)->item_OnDrop(*it, player,
+			PLAYER_TO_SA(player)->item_OnDrop(output_replacement, player,
 				player->getBasePosition());
-			if (count >= it->count) {
+			if (count >= output_replacement.count) {
 				errorstream << "Couldn't drop replacement stack " <<
-					it->getItemString() << " because drop loop didn't "
+					output_replacement.getItemString() << " because drop loop didn't "
 					"decrease count." << std::endl;
 
 				break;
 			}
-		} while (!it->empty());
+		} while (!output_replacement.empty());
 	}
 
 	infostream<<"ICraftAction::apply(): crafted "
diff --git a/src/inventorymanager.h b/src/inventorymanager.h
index 53830d5c1..9ae92e5f4 100644
--- a/src/inventorymanager.h
+++ b/src/inventorymanager.h
@@ -54,7 +54,7 @@ struct InventoryLocation
 		type = PLAYER;
 		name = name_;
 	}
-	void setNodeMeta(v3s16 p_)
+	void setNodeMeta(const v3s16 &p_)
 	{
 		type = NODEMETA;
 		p = p_;
@@ -105,8 +105,8 @@ struct InventoryAction;
 class InventoryManager
 {
 public:
-	InventoryManager(){}
-	virtual ~InventoryManager(){}
+	InventoryManager() = default;
+	virtual ~InventoryManager() = default;
 
 	// Get an inventory (server and client)
 	virtual Inventory* getInventory(const InventoryLocation &loc){return NULL;}
@@ -131,7 +131,7 @@ struct InventoryAction
 	virtual void apply(InventoryManager *mgr, ServerActiveObject *player,
 			IGameDef *gamedef) = 0;
 	virtual void clientApply(InventoryManager *mgr, IGameDef *gamedef) = 0;
-	virtual ~InventoryAction() {};
+	virtual ~InventoryAction() = default;;
 };
 
 struct IMoveAction : public InventoryAction
@@ -151,7 +151,7 @@ struct IMoveAction : public InventoryAction
 	bool caused_by_move_somewhere = false;
 	u32 move_count = 0;
 
-	IMoveAction() {}
+	IMoveAction() = default;
 
 	IMoveAction(std::istream &is, bool somewhere);
 
@@ -189,7 +189,7 @@ struct IDropAction : public InventoryAction
 	std::string from_list;
 	s16 from_i = -1;
 
-	IDropAction() {}
+	IDropAction() = default;
 
 	IDropAction(std::istream &is);
 
@@ -218,7 +218,7 @@ struct ICraftAction : public InventoryAction
 	u16 count = 0;
 	InventoryLocation craft_inv;
 
-	ICraftAction() {}
+	ICraftAction() = default;
 
 	ICraftAction(std::istream &is);
 
diff --git a/src/itemstackmetadata.cpp b/src/itemstackmetadata.cpp
index 65829fd68..02c548abb 100644
--- a/src/itemstackmetadata.cpp
+++ b/src/itemstackmetadata.cpp
@@ -13,11 +13,9 @@ void ItemStackMetadata::serialize(std::ostream &os) const
 {
 	std::ostringstream os2;
 	os2 << DESERIALIZE_START;
-	for (StringMap::const_iterator
-			it = m_stringvars.begin();
-			it != m_stringvars.end(); ++it) {
-		os2 << it->first << DESERIALIZE_KV_DELIM
-		    << it->second << DESERIALIZE_PAIR_DELIM;
+	for (const auto &stringvar : m_stringvars) {
+		os2 << stringvar.first << DESERIALIZE_KV_DELIM
+		    << stringvar.second << DESERIALIZE_PAIR_DELIM;
 	}
 	os << serializeJsonStringIfNeeded(os2.str());
 }