From d024f79b0e12e179e21100910957bf6ba809621d Mon Sep 17 00:00:00 2001
From: Anders Jenbo <anders@jenbo.dk>
Date: Wed, 21 Apr 2021 12:08:11 +0200
Subject: [PATCH] =?UTF-8?q?=F0=9F=A7=B9=20performance-unnecessary-value-pa?=
 =?UTF-8?q?ram?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 Source/DiabloUI/art_draw.cpp       |  2 +-
 Source/DiabloUI/art_draw.h         |  2 +-
 Source/DiabloUI/diabloui.cpp       |  6 ++---
 Source/DiabloUI/diabloui.h         |  6 ++---
 Source/DiabloUI/dialogs.cpp        | 10 +++++---
 Source/DiabloUI/dialogs.h          |  2 +-
 Source/controls/modifier_hints.cpp |  8 +++---
 Source/controls/modifier_hints.h   |  2 +-
 Source/doom.cpp                    |  2 +-
 Source/doom.h                      |  2 +-
 Source/dvlnet/tcp_server.cpp       | 25 ++++++++++---------
 Source/dvlnet/tcp_server.h         | 22 ++++++++--------
 Source/engine.cpp                  | 24 +++++++++---------
 Source/engine.h                    | 24 +++++++++---------
 Source/error.cpp                   |  2 +-
 Source/error.h                     |  2 +-
 Source/gmenu.cpp                   |  8 +++---
 Source/gmenu.h                     |  4 +--
 Source/help.cpp                    |  4 +--
 Source/help.h                      |  2 +-
 Source/inv.cpp                     |  4 +--
 Source/inv.h                       |  4 +--
 Source/items.cpp                   |  6 ++---
 Source/items.h                     |  2 +-
 Source/minitext.cpp                |  4 +--
 Source/minitext.h                  |  4 +--
 Source/plrmsg.cpp                  |  4 +--
 Source/plrmsg.h                    |  2 +-
 Source/qol.cpp                     |  2 +-
 Source/qol.h                       |  2 +-
 Source/quests.cpp                  |  4 +--
 Source/quests.h                    |  2 +-
 Source/scrollrt.cpp                | 40 +++++++++++++++---------------
 Source/scrollrt.h                  |  2 +-
 Source/stores.cpp                  |  8 +++---
 Source/stores.h                    |  4 +--
 Source/storm/storm_net.cpp         |  3 ++-
 37 files changed, 130 insertions(+), 126 deletions(-)

diff --git a/Source/DiabloUI/art_draw.cpp b/Source/DiabloUI/art_draw.cpp
index fc3cf4f7c..9e411b378 100644
--- a/Source/DiabloUI/art_draw.cpp
+++ b/Source/DiabloUI/art_draw.cpp
@@ -37,7 +37,7 @@ void DrawArt(Sint16 screenX, Sint16 screenY, Art *art, int nFrame, Uint16 srcW,
 		ErrSdl();
 }
 
-void DrawArt(CelOutputBuffer out, Sint16 screenX, Sint16 screenY, Art *art, int nFrame, Uint16 srcW, Uint16 srcH)
+void DrawArt(const CelOutputBuffer &out, Sint16 screenX, Sint16 screenY, Art *art, int nFrame, Uint16 srcW, Uint16 srcH)
 {
 	if (screenY >= gnScreenHeight || screenX >= gnScreenWidth || art->surface == nullptr)
 		return;
diff --git a/Source/DiabloUI/art_draw.h b/Source/DiabloUI/art_draw.h
index 7fc69571e..cc894cdfc 100644
--- a/Source/DiabloUI/art_draw.h
+++ b/Source/DiabloUI/art_draw.h
@@ -6,7 +6,7 @@ namespace devilution {
 
 void DrawArt(Sint16 screenX, Sint16 screenY, Art *art, int nFrame = 0, Uint16 srcW = 0, Uint16 srcH = 0);
 
-void DrawArt(CelOutputBuffer out, Sint16 screenX, Sint16 screenY, Art *art, int nFrame = 0, Uint16 srcW = 0, Uint16 srcH = 0);
+void DrawArt(const CelOutputBuffer &out, Sint16 screenX, Sint16 screenY, Art *art, int nFrame = 0, Uint16 srcW = 0, Uint16 srcH = 0);
 
 void DrawAnimatedArt(Art *art, int screenX, int screenY);
 
diff --git a/Source/DiabloUI/diabloui.cpp b/Source/DiabloUI/diabloui.cpp
index 75c2f93c3..b90e264ec 100644
--- a/Source/DiabloUI/diabloui.cpp
+++ b/Source/DiabloUI/diabloui.cpp
@@ -74,7 +74,7 @@ struct scrollBarState {
 
 } // namespace
 
-void UiInitList(int count, void (*fnFocus)(int value), void (*fnSelect)(int value), void (*fnEsc)(), std::vector<UiItemBase *> items, bool itemsWraps, bool (*fnYesNo)())
+void UiInitList(int count, void (*fnFocus)(int value), void (*fnSelect)(int value), void (*fnEsc)(), const std::vector<UiItemBase *> &items, bool itemsWraps, bool (*fnYesNo)())
 {
 	SelectedItem = 0;
 	SelectedItemMax = std::max(count - 1, 0);
@@ -916,13 +916,13 @@ void LoadPalInMem(const SDL_Color *pPal)
 	}
 }
 
-void UiRenderItems(std::vector<UiItemBase *> items)
+void UiRenderItems(const std::vector<UiItemBase *> &items)
 {
 	for (auto &item : items)
 		RenderItem(item);
 }
 
-bool UiItemMouseEvents(SDL_Event *event, std::vector<UiItemBase *> items)
+bool UiItemMouseEvents(SDL_Event *event, const std::vector<UiItemBase *> &items)
 {
 	if (items.size() == 0) {
 		return false;
diff --git a/Source/DiabloUI/diabloui.h b/Source/DiabloUI/diabloui.h
index f874def68..fdc1ea58f 100644
--- a/Source/DiabloUI/diabloui.h
+++ b/Source/DiabloUI/diabloui.h
@@ -119,7 +119,7 @@ int UiSelectProvider(GameData *gameData);
 void UiSetupPlayerInfo(char *infostr, _uiheroinfo *pInfo, Uint32 type);
 void UiFadeIn();
 void UiHandleEvents(SDL_Event *event);
-bool UiItemMouseEvents(SDL_Event *event, std::vector<UiItemBase *> items);
+bool UiItemMouseEvents(SDL_Event *event, const std::vector<UiItemBase *> &items);
 Sint16 GetCenterOffset(Sint16 w, Sint16 bw = 0);
 void LoadPalInMem(const SDL_Color *pPal);
 void DrawMouse();
@@ -129,11 +129,11 @@ void UiAddLogo(std::vector<UiItemBase *> *vecDialog, int size = LOGO_MED, int y
 void UiFocusNavigationSelect();
 void UiFocusNavigationEsc();
 void UiFocusNavigationYesNo();
-void UiInitList(int count, void (*fnFocus)(int value), void (*fnSelect)(int value), void (*fnEsc)(), std::vector<UiItemBase *> items, bool wraps = false, bool (*fnYesNo)() = NULL);
+void UiInitList(int count, void (*fnFocus)(int value), void (*fnSelect)(int value), void (*fnEsc)(), const std::vector<UiItemBase *> &items, bool wraps = false, bool (*fnYesNo)() = NULL);
 void UiInitScrollBar(UiScrollBar *ui_sb, std::size_t viewport_size, const std::size_t *current_offset);
 void UiClearScreen();
 void UiPollAndRender();
-void UiRenderItems(std::vector<UiItemBase *> items);
+void UiRenderItems(const std::vector<UiItemBase *> &items);
 void UiInitList_clear();
 
 void mainmenu_restart_repintro();
diff --git a/Source/DiabloUI/dialogs.cpp b/Source/DiabloUI/dialogs.cpp
index aaff61a36..062dae8e7 100644
--- a/Source/DiabloUI/dialogs.cpp
+++ b/Source/DiabloUI/dialogs.cpp
@@ -1,5 +1,7 @@
 #include "DiabloUI/dialogs.h"
 
+#include <utility>
+
 #include "DiabloUI/button.h"
 #include "DiabloUI/diabloui.h"
 #include "DiabloUI/errorart.h"
@@ -216,7 +218,7 @@ void Deinit()
 	vecOkDialog.clear();
 }
 
-void DialogLoop(std::vector<UiItemBase *> items, std::vector<UiItemBase *> renderBehind)
+void DialogLoop(const std::vector<UiItemBase *> &items, const std::vector<UiItemBase *> &renderBehind)
 {
 	SDL_Event event;
 	dialogEnd = false;
@@ -254,7 +256,7 @@ void DialogLoop(std::vector<UiItemBase *> items, std::vector<UiItemBase *> rende
 
 } // namespace
 
-void UiOkDialog(const char *text, const char *caption, bool error, std::vector<UiItemBase *> renderBehind)
+void UiOkDialog(const char *text, const char *caption, bool error, const std::vector<UiItemBase *> &renderBehind)
 {
 	static bool inDialog = false;
 
@@ -283,7 +285,7 @@ void UiOkDialog(const char *text, const char *caption, bool error, std::vector<U
 
 void UiErrorOkDialog(const char *text, const char *caption, std::vector<UiItemBase *> renderBehind)
 {
-	UiOkDialog(text, caption, /*error=*/true, renderBehind);
+	UiOkDialog(text, caption, /*error=*/true, std::move(renderBehind));
 }
 
 void UiErrorOkDialog(const char *text, const char *caption, bool error)
@@ -293,7 +295,7 @@ void UiErrorOkDialog(const char *text, const char *caption, bool error)
 
 void UiErrorOkDialog(const char *text, std::vector<UiItemBase *> renderBehind)
 {
-	UiErrorOkDialog(text, nullptr, renderBehind);
+	UiErrorOkDialog(text, nullptr, std::move(renderBehind));
 }
 
 } // namespace devilution
diff --git a/Source/DiabloUI/dialogs.h b/Source/DiabloUI/dialogs.h
index b0400decd..b5a3df012 100644
--- a/Source/DiabloUI/dialogs.h
+++ b/Source/DiabloUI/dialogs.h
@@ -8,6 +8,6 @@ namespace devilution {
 
 void UiErrorOkDialog(const char *text, std::vector<UiItemBase *> renderBehind);
 void UiErrorOkDialog(const char *text, const char *caption, std::vector<UiItemBase *> renderBehind);
-void UiOkDialog(const char *text, const char *caption, bool error, std::vector<UiItemBase *> renderBehind);
+void UiOkDialog(const char *text, const char *caption, bool error, const std::vector<UiItemBase *> &renderBehind);
 
 } // namespace devilution
diff --git a/Source/controls/modifier_hints.cpp b/Source/controls/modifier_hints.cpp
index a79ab64ef..8f9c2aa1f 100644
--- a/Source/controls/modifier_hints.cpp
+++ b/Source/controls/modifier_hints.cpp
@@ -93,7 +93,7 @@ text_color CircleMenuHintTextColor(bool active)
 	return active ? COL_BLUE : COL_GOLD;
 }
 
-void DrawCircleMenuHint(CelOutputBuffer out, const CircleMenuHint &hint, int x, int y)
+void DrawCircleMenuHint(const CelOutputBuffer &out, const CircleMenuHint &hint, int x, int y)
 {
 	const int kLineHeight = 25;
 	PrintGameStr(out, x + hint.x_mid - hint.top_w / 2, y, hint.top, CircleMenuHintTextColor(IsTopActive(hint)));
@@ -109,7 +109,7 @@ void DrawCircleMenuHint(CelOutputBuffer out, const CircleMenuHint &hint, int x,
 const int kCircleMarginX = 16;
 const int kCirclesTop = 76;
 
-void DrawStartModifierMenu(CelOutputBuffer out)
+void DrawStartModifierMenu(const CelOutputBuffer &out)
 {
 	if (!start_modifier_active)
 		return;
@@ -119,7 +119,7 @@ void DrawStartModifierMenu(CelOutputBuffer out)
 	DrawCircleMenuHint(out, kButtons, PANEL_LEFT + PANEL_WIDTH - kButtons.width() - kCircleMarginX, PANEL_TOP - kCirclesTop);
 }
 
-void DrawSelectModifierMenu(CelOutputBuffer out)
+void DrawSelectModifierMenu(const CelOutputBuffer &out)
 {
 	if (!select_modifier_active)
 		return;
@@ -133,7 +133,7 @@ void DrawSelectModifierMenu(CelOutputBuffer out)
 
 } // namespace
 
-void DrawControllerModifierHints(CelOutputBuffer out)
+void DrawControllerModifierHints(const CelOutputBuffer &out)
 {
 	DrawStartModifierMenu(out);
 	DrawSelectModifierMenu(out);
diff --git a/Source/controls/modifier_hints.h b/Source/controls/modifier_hints.h
index a5815f5cd..bf9376834 100644
--- a/Source/controls/modifier_hints.h
+++ b/Source/controls/modifier_hints.h
@@ -4,6 +4,6 @@
 
 namespace devilution {
 
-void DrawControllerModifierHints(CelOutputBuffer out);
+void DrawControllerModifierHints(const CelOutputBuffer &out);
 
 } // namespace devilution
diff --git a/Source/doom.cpp b/Source/doom.cpp
index d0ec778cc..0755f7d5d 100644
--- a/Source/doom.cpp
+++ b/Source/doom.cpp
@@ -88,7 +88,7 @@ void doom_close()
 	doom_cleanup();
 }
 
-void doom_draw(CelOutputBuffer out)
+void doom_draw(const CelOutputBuffer &out)
 {
 	if (!doomflag) {
 		return;
diff --git a/Source/doom.h b/Source/doom.h
index 1a0e41cc7..e1d41cf66 100644
--- a/Source/doom.h
+++ b/Source/doom.h
@@ -15,6 +15,6 @@ extern int DoomQuestState;
 int doom_get_frame_from_time();
 void doom_init();
 void doom_close();
-void doom_draw(CelOutputBuffer out);
+void doom_draw(const CelOutputBuffer &out);
 
 } // namespace devilution
diff --git a/Source/dvlnet/tcp_server.cpp b/Source/dvlnet/tcp_server.cpp
index b81246e2c..9b46fb6cf 100644
--- a/Source/dvlnet/tcp_server.cpp
+++ b/Source/dvlnet/tcp_server.cpp
@@ -3,15 +3,16 @@
 #include <chrono>
 #include <functional>
 #include <memory>
+#include <utility>
 
 #include "dvlnet/base.h"
 
 namespace devilution::net {
 
-tcp_server::tcp_server(asio::io_context &ioc, std::string bindaddr,
+tcp_server::tcp_server(asio::io_context &ioc, const std::string &bindaddr,
     unsigned short port, std::string pw)
     : ioc(ioc)
-    , pktfty(pw)
+    , pktfty(std::move(pw))
 {
 	auto addr = asio::ip::address::from_string(bindaddr);
 	auto ep = asio::ip::tcp::endpoint(addr, port);
@@ -54,7 +55,7 @@ bool tcp_server::empty()
 	return true;
 }
 
-void tcp_server::start_recv(scc con)
+void tcp_server::start_recv(const scc &con)
 {
 	con->socket.async_receive(asio::buffer(con->recv_buffer),
 	    std::bind(&tcp_server::handle_recv, this, con,
@@ -62,7 +63,7 @@ void tcp_server::start_recv(scc con)
 	        std::placeholders::_2));
 }
 
-void tcp_server::handle_recv(scc con, const asio::error_code &ec,
+void tcp_server::handle_recv(const scc &con, const asio::error_code &ec,
     size_t bytes_read)
 {
 	if (ec || bytes_read == 0) {
@@ -90,14 +91,14 @@ void tcp_server::handle_recv(scc con, const asio::error_code &ec,
 	start_recv(con);
 }
 
-void tcp_server::send_connect(scc con)
+void tcp_server::send_connect(const scc &con)
 {
 	auto pkt = pktfty.make_packet<PT_CONNECT>(PLR_MASTER, PLR_BROADCAST,
 	    con->plr);
 	send_packet(*pkt);
 }
 
-void tcp_server::handle_recv_newplr(scc con, packet &pkt)
+void tcp_server::handle_recv_newplr(const scc &con, packet &pkt)
 {
 	auto newplr = next_free();
 	if (newplr == PLR_BROADCAST)
@@ -133,7 +134,7 @@ void tcp_server::send_packet(packet &pkt)
 	}
 }
 
-void tcp_server::start_send(scc con, packet &pkt)
+void tcp_server::start_send(const scc &con, packet &pkt)
 {
 	const auto *frame = new buffer_t(frame_queue::make_frame(pkt.data()));
 	auto buf = asio::buffer(*frame);
@@ -144,7 +145,7 @@ void tcp_server::start_send(scc con, packet &pkt)
 	    });
 }
 
-void tcp_server::handle_send(scc con, const asio::error_code &ec,
+void tcp_server::handle_send(const scc &con, const asio::error_code &ec,
     size_t bytes_sent)
 {
 	// empty for now
@@ -159,7 +160,7 @@ void tcp_server::start_accept()
 	        std::placeholders::_1));
 }
 
-void tcp_server::handle_accept(scc con, const asio::error_code &ec)
+void tcp_server::handle_accept(const scc &con, const asio::error_code &ec)
 {
 	if (ec)
 		return;
@@ -175,14 +176,14 @@ void tcp_server::handle_accept(scc con, const asio::error_code &ec)
 	start_accept();
 }
 
-void tcp_server::start_timeout(scc con)
+void tcp_server::start_timeout(const scc &con)
 {
 	con->timer.expires_after(std::chrono::seconds(1));
 	con->timer.async_wait(std::bind(&tcp_server::handle_timeout, this, con,
 	    std::placeholders::_1));
 }
 
-void tcp_server::handle_timeout(scc con, const asio::error_code &ec)
+void tcp_server::handle_timeout(const scc &con, const asio::error_code &ec)
 {
 	if (ec) {
 		drop_connection(con);
@@ -199,7 +200,7 @@ void tcp_server::handle_timeout(scc con, const asio::error_code &ec)
 	start_timeout(con);
 }
 
-void tcp_server::drop_connection(scc con)
+void tcp_server::drop_connection(const scc &con)
 {
 	if (con->plr != PLR_BROADCAST) {
 		auto pkt = pktfty.make_packet<PT_DISCONNECT>(PLR_MASTER, PLR_BROADCAST,
diff --git a/Source/dvlnet/tcp_server.h b/Source/dvlnet/tcp_server.h
index b9a355860..470657908 100644
--- a/Source/dvlnet/tcp_server.h
+++ b/Source/dvlnet/tcp_server.h
@@ -25,7 +25,7 @@ public:
 
 class tcp_server {
 public:
-	tcp_server(asio::io_context &ioc, std::string bindaddr,
+	tcp_server(asio::io_context &ioc, const std::string &bindaddr,
 	    unsigned short port, std::string pw);
 	std::string localhost_self();
 	void close();
@@ -61,18 +61,18 @@ private:
 	plr_t next_free();
 	bool empty();
 	void start_accept();
-	void handle_accept(scc con, const asio::error_code &ec);
-	void start_recv(scc con);
-	void handle_recv(scc con, const asio::error_code &ec, size_t bytes_read);
-	void handle_recv_newplr(scc con, packet &pkt);
+	void handle_accept(const scc &con, const asio::error_code &ec);
+	void start_recv(const scc &con);
+	void handle_recv(const scc &con, const asio::error_code &ec, size_t bytes_read);
+	void handle_recv_newplr(const scc &con, packet &pkt);
 	void handle_recv_packet(packet &pkt);
-	void send_connect(scc con);
+	void send_connect(const scc &con);
 	void send_packet(packet &pkt);
-	void start_send(scc con, packet &pkt);
-	void handle_send(scc con, const asio::error_code &ec, size_t bytes_sent);
-	void start_timeout(scc con);
-	void handle_timeout(scc con, const asio::error_code &ec);
-	void drop_connection(scc con);
+	void start_send(const scc &con, packet &pkt);
+	void handle_send(const scc &con, const asio::error_code &ec, size_t bytes_sent);
+	void start_timeout(const scc &con);
+	void handle_timeout(const scc &con, const asio::error_code &ec);
+	void drop_connection(const scc &con);
 };
 
 } //namespace net
diff --git a/Source/engine.cpp b/Source/engine.cpp
index d9056ba7d..22c06d68f 100644
--- a/Source/engine.cpp
+++ b/Source/engine.cpp
@@ -33,7 +33,7 @@ const Uint32 RndInc = 1;
  */
 const Uint32 RndMult = 0x015A4E35;
 
-void CelDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void CelDrawTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	int nDataSize;
 	BYTE *pRLEBytes;
@@ -43,7 +43,7 @@ void CelDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, in
 	CelBlitSafeTo(out, sx, sy, pRLEBytes, nDataSize, nWidth);
 }
 
-void CelClippedDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void CelClippedDrawTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	BYTE *pRLEBytes;
 	int nDataSize;
@@ -55,7 +55,7 @@ void CelClippedDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int n
 	CelBlitSafeTo(out, sx, sy, pRLEBytes, nDataSize, nWidth);
 }
 
-void CelDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, BYTE *tbl)
+void CelDrawLightTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, BYTE *tbl)
 {
 	int nDataSize;
 	BYTE *pRLEBytes;
@@ -70,7 +70,7 @@ void CelDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCe
 		CelBlitSafeTo(out, sx, sy, pRLEBytes, nDataSize, nWidth);
 }
 
-void CelClippedDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void CelClippedDrawLightTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	int nDataSize;
 	BYTE *pRLEBytes;
@@ -158,7 +158,7 @@ void CelBlitSafeTo(CelOutputBuffer out, int sx, int sy, BYTE *pRLEBytes, int nDa
 	}
 }
 
-void CelClippedDrawSafeTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void CelClippedDrawSafeTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	BYTE *pRLEBytes;
 	int nDataSize;
@@ -365,7 +365,7 @@ static void CelBlitLightBlendedSafeTo(CelOutputBuffer out, int sx, int sy, BYTE
 	}
 }
 
-void CelClippedBlitLightTransTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void CelClippedBlitLightTransTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	int nDataSize;
 	BYTE *pRLEBytes;
@@ -516,14 +516,14 @@ void CelBlitOutlineTo(CelOutputBuffer out, BYTE col, int sx, int sy, BYTE *pCelB
 	}
 }
 
-void SetPixel(CelOutputBuffer out, int sx, int sy, BYTE col)
+void SetPixel(const CelOutputBuffer &out, int sx, int sy, BYTE col)
 {
 	if (!out.in_bounds(sx, sy))
 		return;
 	*out.at(sx, sy) = col;
 }
 
-void DrawLineTo(CelOutputBuffer out, int x0, int y0, int x1, int y1, BYTE color_index)
+void DrawLineTo(const CelOutputBuffer &out, int x0, int y0, int x1, int y1, BYTE color_index)
 {
 	int i, dx, dy, steps;
 	float ix, iy, sx, sy;
@@ -566,7 +566,7 @@ static void DrawHalfTransparentStippledRectTo(CelOutputBuffer out, int sx, int s
 	}
 }
 
-void DrawHalfTransparentRectTo(CelOutputBuffer out, int sx, int sy, int width, int height)
+void DrawHalfTransparentRectTo(const CelOutputBuffer &out, int sx, int sy, int width, int height)
 {
 	if (sgOptions.Graphics.bBlendedTransparancy) {
 		DrawHalfTransparentBlendedRectTo(out, sx, sy, width, height);
@@ -1009,7 +1009,7 @@ static void Cl2BlitLightSafe(CelOutputBuffer out, int sx, int sy, BYTE *pRLEByte
 	}
 }
 
-void Cl2Draw(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void Cl2Draw(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	BYTE *pRLEBytes;
 	int nDataSize;
@@ -1036,7 +1036,7 @@ void Cl2DrawOutline(CelOutputBuffer out, BYTE col, int sx, int sy, BYTE *pCelBuf
 	Cl2BlitOutlineSafe(out, sx, sy, pRLEBytes, nDataSize, nWidth, col);
 }
 
-void Cl2DrawLightTbl(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, char light)
+void Cl2DrawLightTbl(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, char light)
 {
 	int nDataSize, idx;
 	BYTE *pRLEBytes;
@@ -1055,7 +1055,7 @@ void Cl2DrawLightTbl(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nC
 	Cl2BlitLightSafe(out, sx, sy, pRLEBytes, nDataSize, nWidth, &pLightTbl[idx]);
 }
 
-void Cl2DrawLight(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
+void Cl2DrawLight(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth)
 {
 	int nDataSize;
 	BYTE *pRLEBytes;
diff --git a/Source/engine.h b/Source/engine.h
index 195c0af15..8c4f9e27c 100644
--- a/Source/engine.h
+++ b/Source/engine.h
@@ -223,7 +223,7 @@ struct CelOutputBuffer {
  * @param nCel CEL frame number
  * @param nWidth Width of sprite
  */
-void CelDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void CelDrawTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @briefBlit CEL sprite to the given buffer, does not perform bounds-checking.
@@ -245,7 +245,7 @@ void CelDrawUnsafeTo(CelOutputBuffer out, int x, int y, BYTE *pCelBuff, int nCel
  * @param nCel CEL frame number
  * @param nWidth Width of sprite
  */
-void CelClippedDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void CelClippedDrawTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @brief Blit CEL sprite, and apply lighting, to the back buffer at the given coordinates
@@ -256,7 +256,7 @@ void CelClippedDrawTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int n
  * @param nCel CEL frame number
  * @param nWidth Width of sprite
  */
-void CelDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, BYTE *tbl);
+void CelDrawLightTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, BYTE *tbl);
 
 /**
  * @brief Same as CelDrawLightTo but with the option to skip parts of the top and bottom of the sprite
@@ -267,7 +267,7 @@ void CelDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCe
  * @param nCel CEL frame number
  * @param nWidth Width of sprite
  */
-void CelClippedDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void CelClippedDrawLightTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @brief Same as CelBlitLightTransSafeTo
@@ -278,7 +278,7 @@ void CelClippedDrawLightTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff,
  * @param nCel CEL frame number
  * @param nWidth Width of sprite
  */
-void CelClippedBlitLightTransTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void CelClippedBlitLightTransTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @brief Blit CEL sprite, and apply lighting, to the back buffer at the given coordinates, translated to a red hue
@@ -312,7 +312,7 @@ void CelBlitSafeTo(CelOutputBuffer out, int sx, int sy, BYTE *pRLEBytes, int nDa
  * @param nCel CEL frame number
  * @param nWidth Width of sprite
  */
-void CelClippedDrawSafeTo(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void CelClippedDrawSafeTo(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @brief Blit CEL sprite, and apply lighting, to the given buffer, checks for drawing outside the buffer
@@ -369,7 +369,7 @@ void CelBlitOutlineTo(CelOutputBuffer out, BYTE col, int sx, int sy, BYTE *pCelB
  * @param sy Target buffer coordinate
  * @param col Color index from current palette
  */
-void SetPixel(CelOutputBuffer out, int sx, int sy, BYTE col);
+void SetPixel(const CelOutputBuffer &out, int sx, int sy, BYTE col);
 
 /**
  * @brief Blit CL2 sprite, to the back buffer at the given coordianates
@@ -380,7 +380,7 @@ void SetPixel(CelOutputBuffer out, int sx, int sy, BYTE col);
  * @param nCel CL2 frame number
  * @param nWidth Width of sprite
  */
-void Cl2Draw(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void Cl2Draw(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @brief Blit a solid colder shape one pixel larger then the given sprite shape, to the given buffer at the given coordianates
@@ -404,7 +404,7 @@ void Cl2DrawOutline(CelOutputBuffer out, BYTE col, int sx, int sy, BYTE *pCelBuf
  * @param nWidth Width of sprite
  * @param light Light shade to use
  */
-void Cl2DrawLightTbl(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, char light);
+void Cl2DrawLightTbl(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth, char light);
 
 /**
  * @brief Blit CL2 sprite, and apply lighting, to the given buffer at the given coordinates
@@ -415,7 +415,7 @@ void Cl2DrawLightTbl(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nC
  * @param nCel CL2 frame number
  * @param nWidth Width of sprite
  */
-void Cl2DrawLight(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
+void Cl2DrawLight(const CelOutputBuffer &out, int sx, int sy, BYTE *pCelBuff, int nCel, int nWidth);
 
 /**
  * @brief Draw a line in the target buffer
@@ -426,7 +426,7 @@ void Cl2DrawLight(CelOutputBuffer out, int sx, int sy, BYTE *pCelBuff, int nCel,
  * @param y1 Back buffer coordinate
  * @param color_index Color index from current palette
  */
-void DrawLineTo(CelOutputBuffer out, int x0, int y0, int x1, int y1, BYTE color_index);
+void DrawLineTo(const CelOutputBuffer &out, int x0, int y0, int x1, int y1, BYTE color_index);
 
 /**
  * Draws a half-transparent rectangle by blacking out odd pixels on odd lines,
@@ -439,7 +439,7 @@ void DrawLineTo(CelOutputBuffer out, int x0, int y0, int x1, int y1, BYTE color_
  * @param width Rectangle width
  * @param height Rectangle height
  */
-void DrawHalfTransparentRectTo(CelOutputBuffer out, int sx, int sy, int width, int height);
+void DrawHalfTransparentRectTo(const CelOutputBuffer &out, int sx, int sy, int width, int height);
 
 /**
  * @brief Calculate the best fit direction between two points
diff --git a/Source/error.cpp b/Source/error.cpp
index 4c7bcfb46..51e6cec0c 100644
--- a/Source/error.cpp
+++ b/Source/error.cpp
@@ -104,7 +104,7 @@ void ClrDiabloMsg()
 
 #define DIALOG_Y ((gnScreenHeight - PANEL_HEIGHT) / 2 - 18)
 
-void DrawDiabloMsg(CelOutputBuffer out)
+void DrawDiabloMsg(const CelOutputBuffer &out)
 {
 	int i, len, width, sx, sy;
 	BYTE c;
diff --git a/Source/error.h b/Source/error.h
index a21f296bc..3c267ca9c 100644
--- a/Source/error.h
+++ b/Source/error.h
@@ -74,6 +74,6 @@ extern diablo_message msgflag;
 
 void InitDiabloMsg(diablo_message e);
 void ClrDiabloMsg();
-void DrawDiabloMsg(CelOutputBuffer out);
+void DrawDiabloMsg(const CelOutputBuffer &out);
 
 } // namespace devilution
diff --git a/Source/gmenu.cpp b/Source/gmenu.cpp
index 41cdd3a1f..95a62695d 100644
--- a/Source/gmenu.cpp
+++ b/Source/gmenu.cpp
@@ -54,7 +54,7 @@ const BYTE lfontkern[] = {
 	11, 10, 12, 11, 21, 23
 };
 
-static void gmenu_print_text(CelOutputBuffer out, int x, int y, const char *pszStr)
+static void gmenu_print_text(const CelOutputBuffer &out, int x, int y, const char *pszStr)
 {
 	BYTE c;
 
@@ -67,7 +67,7 @@ static void gmenu_print_text(CelOutputBuffer out, int x, int y, const char *pszS
 	}
 }
 
-void gmenu_draw_pause(CelOutputBuffer out)
+void gmenu_draw_pause(const CelOutputBuffer &out)
 {
 	if (currlevel != 0)
 		RedBack(out);
@@ -211,7 +211,7 @@ static int gmenu_get_lfont(TMenuItem *pItem)
 	return i - 2;
 }
 
-static void gmenu_draw_menu_item(CelOutputBuffer out, TMenuItem *pItem, int y)
+static void gmenu_draw_menu_item(const CelOutputBuffer &out, TMenuItem *pItem, int y)
 {
 	DWORD w, x, nSteps, step, pos;
 	w = gmenu_get_lfont(pItem);
@@ -245,7 +245,7 @@ static void GameMenuMove()
 		gmenu_up_down(move_dir.y == AxisDirectionY_DOWN);
 }
 
-void gmenu_draw(CelOutputBuffer out)
+void gmenu_draw(const CelOutputBuffer &out)
 {
 	int y;
 	TMenuItem *i;
diff --git a/Source/gmenu.h b/Source/gmenu.h
index 31d484644..b4dc81b29 100644
--- a/Source/gmenu.h
+++ b/Source/gmenu.h
@@ -20,12 +20,12 @@ struct TMenuItem {
 
 extern TMenuItem *sgpCurrentMenu;
 
-void gmenu_draw_pause(CelOutputBuffer out);
+void gmenu_draw_pause(const CelOutputBuffer &out);
 void FreeGMenu();
 void gmenu_init_menu();
 bool gmenu_is_active();
 void gmenu_set_items(TMenuItem *pItem, void (*gmFunc)(TMenuItem *));
-void gmenu_draw(CelOutputBuffer out);
+void gmenu_draw(const CelOutputBuffer &out);
 bool gmenu_presskeys(int vkey);
 bool gmenu_on_mouse_move();
 bool gmenu_left_mouse(bool isDown);
diff --git a/Source/help.cpp b/Source/help.cpp
index 9f5b0bb53..5a82eb6d6 100644
--- a/Source/help.cpp
+++ b/Source/help.cpp
@@ -457,7 +457,7 @@ void InitHelp()
 	helpflag = false;
 }
 
-static void DrawHelpLine(CelOutputBuffer out, int x, int y, char *text, text_color color)
+static void DrawHelpLine(const CelOutputBuffer &out, int x, int y, char *text, text_color color)
 {
 	int sx, sy, width;
 	BYTE c;
@@ -478,7 +478,7 @@ static void DrawHelpLine(CelOutputBuffer out, int x, int y, char *text, text_col
 	}
 }
 
-void DrawHelp(CelOutputBuffer out)
+void DrawHelp(const CelOutputBuffer &out)
 {
 	int i, c, w;
 	const char *s;
diff --git a/Source/help.h b/Source/help.h
index 19a51c09c..cf2b4c569 100644
--- a/Source/help.h
+++ b/Source/help.h
@@ -12,7 +12,7 @@ namespace devilution {
 extern bool helpflag;
 
 void InitHelp();
-void DrawHelp(CelOutputBuffer out);
+void DrawHelp(const CelOutputBuffer &out);
 void DisplayHelp();
 void HelpScrollUp();
 void HelpScrollDown();
diff --git a/Source/inv.cpp b/Source/inv.cpp
index f273b9204..97a75a16c 100644
--- a/Source/inv.cpp
+++ b/Source/inv.cpp
@@ -168,7 +168,7 @@ static void InvDrawSlotBack(CelOutputBuffer out, int X, int Y, int W, int H)
 	}
 }
 
-void DrawInv(CelOutputBuffer out)
+void DrawInv(const CelOutputBuffer &out)
 {
 	int frame, frame_width, i, j, ii;
 	BYTE *cels;
@@ -300,7 +300,7 @@ void DrawInv(CelOutputBuffer out)
 	}
 }
 
-void DrawInvBelt(CelOutputBuffer out)
+void DrawInvBelt(const CelOutputBuffer &out)
 {
 	int i, frame, frame_width;
 	BYTE fi, ff;
diff --git a/Source/inv.h b/Source/inv.h
index e444684fb..d4f622862 100644
--- a/Source/inv.h
+++ b/Source/inv.h
@@ -84,9 +84,9 @@ void InitInv();
 /**
  * @brief Render the inventory panel to the given buffer.
  */
-void DrawInv(CelOutputBuffer out);
+void DrawInv(const CelOutputBuffer &out);
 
-void DrawInvBelt(CelOutputBuffer out);
+void DrawInvBelt(const CelOutputBuffer &out);
 bool AutoEquipEnabled(const PlayerStruct &player, const ItemStruct &item);
 bool AutoEquip(int playerNumber, const ItemStruct &item, bool persistItem = true);
 bool AutoPlaceItemInInventory(int playerNumber, const ItemStruct &item, bool persistItem = false);
diff --git a/Source/items.cpp b/Source/items.cpp
index d2aa04c5f..d14c85d50 100644
--- a/Source/items.cpp
+++ b/Source/items.cpp
@@ -3823,13 +3823,13 @@ void PrintItemPower(char plidx, ItemStruct *x)
 	}
 }
 
-static void DrawUTextBack(CelOutputBuffer out)
+static void DrawUTextBack(const CelOutputBuffer &out)
 {
 	CelDrawTo(out, RIGHT_PANEL_X - SPANEL_WIDTH + 24, 327, pSTextBoxCels, 1, 271);
 	DrawHalfTransparentRectTo(out, RIGHT_PANEL_X - SPANEL_WIDTH + 27, 28, 265, 297);
 }
 
-void PrintUString(CelOutputBuffer out, int x, int y, bool cjustflag, const char *str, text_color col)
+void PrintUString(const CelOutputBuffer &out, int x, int y, bool cjustflag, const char *str, text_color col)
 {
 	int len, width, sx, sy, i, k;
 	BYTE c;
@@ -3866,7 +3866,7 @@ static void DrawULine(CelOutputBuffer out, int y)
 		memcpy(dst, src, 267); // BUGFIX: should be 267 (fixed)
 }
 
-void DrawUniqueInfo(CelOutputBuffer out)
+void DrawUniqueInfo(const CelOutputBuffer &out)
 {
 	int uid, y;
 
diff --git a/Source/items.h b/Source/items.h
index 90b5d1d86..660aa25b7 100644
--- a/Source/items.h
+++ b/Source/items.h
@@ -420,7 +420,7 @@ void DoRepair(int pnum, int cii);
 void DoRecharge(int pnum, int cii);
 void DoOil(int pnum, int cii);
 void PrintItemPower(char plidx, ItemStruct *x);
-void DrawUniqueInfo(CelOutputBuffer out);
+void DrawUniqueInfo(const CelOutputBuffer &out);
 void PrintItemDetails(ItemStruct *x);
 void PrintItemDur(ItemStruct *x);
 void UseItem(int p, item_misc_id Mid, spell_id spl);
diff --git a/Source/minitext.cpp b/Source/minitext.cpp
index 13c95363e..94dd11dca 100644
--- a/Source/minitext.cpp
+++ b/Source/minitext.cpp
@@ -250,13 +250,13 @@ void InitQTextMsg(int m)
 	PlaySFX(alltext[m].sfxnr);
 }
 
-void DrawQTextBack(CelOutputBuffer out)
+void DrawQTextBack(const CelOutputBuffer &out)
 {
 	CelDrawTo(out, PANEL_X + 24, 327 + UI_OFFSET_Y, pTextBoxCels, 1, 591);
 	DrawHalfTransparentRectTo(out, PANEL_X + 27, UI_OFFSET_Y + 28, 585, 297);
 }
 
-void DrawQText(CelOutputBuffer out)
+void DrawQText(const CelOutputBuffer &out)
 {
 	DrawQTextBack(out);
 	DrawQTextContent();
diff --git a/Source/minitext.h b/Source/minitext.h
index 35fedb2a0..a06a8923f 100644
--- a/Source/minitext.h
+++ b/Source/minitext.h
@@ -18,11 +18,11 @@ void InitQTextMsg(int m);
 /**
  * @brief Draw the quest dialog window decoration and background.
  */
-void DrawQTextBack(CelOutputBuffer out);
+void DrawQTextBack(const CelOutputBuffer &out);
 
 /**
  * @brief Draw the quest dialog window text.
  */
-void DrawQText(CelOutputBuffer out);
+void DrawQText(const CelOutputBuffer &out);
 
 } // namespace devilution
diff --git a/Source/plrmsg.cpp b/Source/plrmsg.cpp
index ab1b5ce0e..7376573ce 100644
--- a/Source/plrmsg.cpp
+++ b/Source/plrmsg.cpp
@@ -89,7 +89,7 @@ void InitPlrMsg()
 	plr_msg_slot = 0;
 }
 
-static void PrintPlrMsg(CelOutputBuffer out, DWORD x, DWORD y, DWORD width, const char *str, text_color col)
+static void PrintPlrMsg(const CelOutputBuffer &out, DWORD x, DWORD y, DWORD width, const char *str, text_color col)
 {
 	int line = 0;
 
@@ -130,7 +130,7 @@ static void PrintPlrMsg(CelOutputBuffer out, DWORD x, DWORD y, DWORD width, cons
 	}
 }
 
-void DrawPlrMsg(CelOutputBuffer out)
+void DrawPlrMsg(const CelOutputBuffer &out)
 {
 	int i;
 	DWORD x = 10;
diff --git a/Source/plrmsg.h b/Source/plrmsg.h
index 2e086458d..dd76a513b 100644
--- a/Source/plrmsg.h
+++ b/Source/plrmsg.h
@@ -21,6 +21,6 @@ size_t EventPlrMsg(const char *pszFmt, ...);
 void SendPlrMsg(int pnum, const char *pszStr);
 void ClearPlrMsg();
 void InitPlrMsg();
-void DrawPlrMsg(CelOutputBuffer out);
+void DrawPlrMsg(const CelOutputBuffer &out);
 
 } // namespace devilution
diff --git a/Source/qol.cpp b/Source/qol.cpp
index 126e665a4..8b3d30898 100644
--- a/Source/qol.cpp
+++ b/Source/qol.cpp
@@ -68,7 +68,7 @@ void InitQol()
 	InitXPBar();
 }
 
-void DrawMonsterHealthBar(CelOutputBuffer out)
+void DrawMonsterHealthBar(const CelOutputBuffer &out)
 {
 	if (!sgOptions.Gameplay.bEnemyHealthBar)
 		return;
diff --git a/Source/qol.h b/Source/qol.h
index 64736bd42..c8617bec5 100644
--- a/Source/qol.h
+++ b/Source/qol.h
@@ -11,7 +11,7 @@ namespace devilution {
 
 void FreeQol();
 void InitQol();
-void DrawMonsterHealthBar(CelOutputBuffer out);
+void DrawMonsterHealthBar(const CelOutputBuffer &out);
 void AutoGoldPickup(int pnum);
 
 } // namespace devilution
diff --git a/Source/quests.cpp b/Source/quests.cpp
index a98e3fb36..3ebfdba3e 100644
--- a/Source/quests.cpp
+++ b/Source/quests.cpp
@@ -728,7 +728,7 @@ void ResyncQuests()
 	}
 }
 
-static void PrintQLString(CelOutputBuffer out, int x, int y, bool cjustflag, const char *str, text_color col)
+static void PrintQLString(const CelOutputBuffer &out, int x, int y, bool cjustflag, const char *str, text_color col)
 {
 	int len, width, i, k, sx, sy;
 	BYTE c;
@@ -761,7 +761,7 @@ static void PrintQLString(CelOutputBuffer out, int x, int y, bool cjustflag, con
 	}
 }
 
-void DrawQuestLog(CelOutputBuffer out)
+void DrawQuestLog(const CelOutputBuffer &out)
 {
 	int y, i;
 
diff --git a/Source/quests.h b/Source/quests.h
index f7e698a2f..2258f1f10 100644
--- a/Source/quests.h
+++ b/Source/quests.h
@@ -85,7 +85,7 @@ void GetReturnLvlPos();
 void LoadPWaterPalette();
 void ResyncMPQuests();
 void ResyncQuests();
-void DrawQuestLog(CelOutputBuffer out);
+void DrawQuestLog(const CelOutputBuffer &out);
 void StartQuestlog();
 void QuestlogUp();
 void QuestlogDown();
diff --git a/Source/scrollrt.cpp b/Source/scrollrt.cpp
index 3bc6a5e62..c22f99c45 100644
--- a/Source/scrollrt.cpp
+++ b/Source/scrollrt.cpp
@@ -248,7 +248,7 @@ static void scrollrt_draw_cursor_item(CelOutputBuffer out)
  * @param sy Output buffer coordinate
  * @param pre Is the sprite in the background
  */
-void DrawMissilePrivate(CelOutputBuffer out, MissileStruct *m, int sx, int sy, bool pre)
+void DrawMissilePrivate(const CelOutputBuffer &out, MissileStruct *m, int sx, int sy, bool pre)
 {
 	if (m->_miPreFlag != pre || !m->_miDrawFlag)
 		return;
@@ -283,7 +283,7 @@ void DrawMissilePrivate(CelOutputBuffer out, MissileStruct *m, int sx, int sy, b
  * @param sy Output buffer coordinate
  * @param pre Is the sprite in the background
  */
-void DrawMissile(CelOutputBuffer out, int x, int y, int sx, int sy, bool pre)
+void DrawMissile(const CelOutputBuffer &out, int x, int y, int sx, int sy, bool pre)
 {
 	int i;
 	MissileStruct *m;
@@ -315,7 +315,7 @@ void DrawMissile(CelOutputBuffer out, int x, int y, int sx, int sy, bool pre)
  * @param my Output buffer coordinate
  * @param m Id of monster
  */
-static void DrawMonster(CelOutputBuffer out, int x, int y, int mx, int my, int m)
+static void DrawMonster(const CelOutputBuffer &out, int x, int y, int mx, int my, int m)
 {
 	if (m < 0 || m >= MAXMONSTERS) {
 		SDL_Log("Draw Monster: tried to draw illegal monster %d", m);
@@ -370,7 +370,7 @@ static void DrawMonster(CelOutputBuffer out, int x, int y, int mx, int my, int m
  * @param sy Output buffer coordinate
  * @param lighting Should lighting be applied
  */
-static void DrawManaShield(CelOutputBuffer out, int pnum, int x, int y, bool lighting)
+static void DrawManaShield(const CelOutputBuffer &out, int pnum, int x, int y, bool lighting)
 {
 	if (!plr[pnum].pManaShield)
 		return;
@@ -405,7 +405,7 @@ static void DrawManaShield(CelOutputBuffer out, int pnum, int x, int y, bool lig
  * @param nCel frame
  * @param nWidth width
  */
-static void DrawPlayer(CelOutputBuffer out, int pnum, int x, int y, int px, int py)
+static void DrawPlayer(const CelOutputBuffer &out, int pnum, int x, int y, int px, int py)
 {
 	if ((dFlags[x][y] & BFLAG_LIT) == 0 && !plr[myplr]._pInfraFlag && leveltype != DTYPE_TOWN) {
 		return;
@@ -473,7 +473,7 @@ static void DrawPlayer(CelOutputBuffer out, int pnum, int x, int y, int px, int
  * @param sx Output buffer coordinate
  * @param sy Output buffer coordinate
  */
-void DrawDeadPlayer(CelOutputBuffer out, int x, int y, int sx, int sy)
+void DrawDeadPlayer(const CelOutputBuffer &out, int x, int y, int sx, int sy)
 {
 	int i, px, py;
 	PlayerStruct *p;
@@ -500,7 +500,7 @@ void DrawDeadPlayer(CelOutputBuffer out, int x, int y, int sx, int sy)
  * @param oy Output buffer coordinate
  * @param pre Is the sprite in the background
  */
-static void DrawObject(CelOutputBuffer out, int x, int y, int ox, int oy, bool pre)
+static void DrawObject(const CelOutputBuffer &out, int x, int y, int ox, int oy, bool pre)
 {
 	if (dObject[x][y] == 0 || light_table_index >= lightmax)
 		return;
@@ -547,7 +547,7 @@ static void DrawObject(CelOutputBuffer out, int x, int y, int ox, int oy, bool p
 	}
 }
 
-static void scrollrt_draw_dungeon(CelOutputBuffer, int, int, int, int);
+static void scrollrt_draw_dungeon(const CelOutputBuffer &, int, int, int, int);
 
 /**
  * @brief Render a cell
@@ -557,7 +557,7 @@ static void scrollrt_draw_dungeon(CelOutputBuffer, int, int, int, int);
  * @param sx Target buffer coordinate
  * @param sy Target buffer coordinate
  */
-static void drawCell(CelOutputBuffer out, int x, int y, int sx, int sy)
+static void drawCell(const CelOutputBuffer &out, int x, int y, int sx, int sy)
 {
 	MICROS *pMap = &dpiece_defs_map_2[x][y];
 	level_piece_id = dPiece[x][y];
@@ -587,7 +587,7 @@ static void drawCell(CelOutputBuffer out, int x, int y, int sx, int sy)
  * @param sx Target buffer coordinate
  * @param sy Target buffer coordinate
  */
-static void drawFloor(CelOutputBuffer out, int x, int y, int sx, int sy)
+static void drawFloor(const CelOutputBuffer &out, int x, int y, int sx, int sy)
 {
 	cel_transparency_active = 0;
 	light_table_index = dLight[x][y];
@@ -613,7 +613,7 @@ static void drawFloor(CelOutputBuffer out, int x, int y, int sx, int sy)
  * @param sy Output buffer coordinate
  * @param pre Is the sprite in the background
  */
-static void DrawItem(CelOutputBuffer out, int x, int y, int sx, int sy, bool pre)
+static void DrawItem(const CelOutputBuffer &out, int x, int y, int sx, int sy, bool pre)
 {
 	int8_t bItem = dItem[x][y];
 
@@ -653,7 +653,7 @@ static void DrawItem(CelOutputBuffer out, int x, int y, int sx, int sy, bool pre
  * @param sx Output buffer coordinate
  * @param sy Output buffer coordinate
  */
-static void DrawMonsterHelper(CelOutputBuffer out, int x, int y, int oy, int sx, int sy)
+static void DrawMonsterHelper(const CelOutputBuffer &out, int x, int y, int oy, int sx, int sy)
 {
 	int mi, px, py;
 	MonsterStruct *pMonster;
@@ -705,7 +705,7 @@ static void DrawMonsterHelper(CelOutputBuffer out, int x, int y, int oy, int sx,
  * @param sx Output buffer coordinate
  * @param sy Output buffer coordinate
  */
-static void DrawPlayerHelper(CelOutputBuffer out, int x, int y, int sx, int sy)
+static void DrawPlayerHelper(const CelOutputBuffer &out, int x, int y, int sx, int sy)
 {
 	int p = dPlayer[x][y];
 	p = p > 0 ? p - 1 : -(p + 1);
@@ -730,7 +730,7 @@ static void DrawPlayerHelper(CelOutputBuffer out, int x, int y, int sx, int sy)
  * @param dx Target buffer coordinate
  * @param dy Target buffer coordinate
  */
-static void scrollrt_draw_dungeon(CelOutputBuffer out, int sx, int sy, int dx, int dy)
+static void scrollrt_draw_dungeon(const CelOutputBuffer &out, int sx, int sy, int dx, int dy)
 {
 	assert((DWORD)sx < MAXDUNX);
 	assert((DWORD)sy < MAXDUNY);
@@ -844,7 +844,7 @@ static void scrollrt_draw_dungeon(CelOutputBuffer out, int sx, int sy, int dx, i
  * @param rows Number of rows
  * @param columns Tile in a row
  */
-static void scrollrt_drawFloor(CelOutputBuffer out, int x, int y, int sx, int sy, int rows, int columns)
+static void scrollrt_drawFloor(const CelOutputBuffer &out, int x, int y, int sx, int sy, int rows, int columns)
 {
 	for (int i = 0; i < rows; i++) {
 		for (int j = 0; j < columns; j++) {
@@ -893,7 +893,7 @@ static void scrollrt_drawFloor(CelOutputBuffer out, int x, int y, int sx, int sy
  * @param rows Number of rows
  * @param columns Tile in a row
  */
-static void scrollrt_draw(CelOutputBuffer out, int x, int y, int sx, int sy, int rows, int columns)
+static void scrollrt_draw(const CelOutputBuffer &out, int x, int y, int sx, int sy, int rows, int columns)
 {
 	// Keep evaluating until MicroTiles can't affect screen
 	rows += MicroTileLen;
@@ -1137,7 +1137,7 @@ void CalcViewportGeometry()
  * @param x Center of view in dPiece coordinate
  * @param y Center of view in dPiece coordinate
  */
-static void DrawGame(CelOutputBuffer full_out, int x, int y)
+static void DrawGame(const CelOutputBuffer &full_out, int x, int y)
 {
 	int sx, sy, columns, rows;
 
@@ -1237,9 +1237,9 @@ static void DrawGame(CelOutputBuffer full_out, int x, int y)
 }
 
 // DevilutionX extension.
-extern void DrawControllerModifierHints(CelOutputBuffer out);
+extern void DrawControllerModifierHints(const CelOutputBuffer &out);
 
-void DrawView(CelOutputBuffer out, int StartX, int StartY)
+void DrawView(const CelOutputBuffer &out, int StartX, int StartY)
 {
 	DrawGame(out, StartX, StartY);
 	if (automapflag) {
@@ -1416,7 +1416,7 @@ void EnableFrameCount()
 /**
  * @brief Display the current average FPS over 1 sec
  */
-static void DrawFPS(CelOutputBuffer out)
+static void DrawFPS(const CelOutputBuffer &out)
 {
 	DWORD tc, frames;
 	char String[12];
diff --git a/Source/scrollrt.h b/Source/scrollrt.h
index 9eb86b2fc..9ad2e072f 100644
--- a/Source/scrollrt.h
+++ b/Source/scrollrt.h
@@ -51,7 +51,7 @@ void CalcViewportGeometry();
  * @param StartX Center of view in dPiece coordinate
  * @param StartY Center of view in dPiece coordinate
  */
-void DrawView(CelOutputBuffer out, int StartX, int StartY);
+void DrawView(const CelOutputBuffer &out, int StartX, int StartY);
 
 void ClearScreenBuffer();
 #ifdef _DEBUG
diff --git a/Source/stores.cpp b/Source/stores.cpp
index 6979dc2d8..6c65bed70 100644
--- a/Source/stores.cpp
+++ b/Source/stores.cpp
@@ -79,13 +79,13 @@ text_color GetItemTextColor(ItemStruct &item)
 	return text_color::COL_WHITE;
 }
 
-void DrawSTextBack(CelOutputBuffer out)
+void DrawSTextBack(const CelOutputBuffer &out)
 {
 	CelDrawTo(out, PANEL_X + 344, 327 + UI_OFFSET_Y, pSTextBoxCels, 1, 271);
 	DrawHalfTransparentRectTo(out, PANEL_X + 347, UI_OFFSET_Y + 28, 265, 297);
 }
 
-void DrawSSlider(CelOutputBuffer out, int y1, int y2)
+void DrawSSlider(const CelOutputBuffer &out, int y1, int y2)
 {
 	int yd1, yd2, yd3;
 
@@ -2160,7 +2160,7 @@ void FreeStoreMem()
 	MemFreeDbg(pSTextSlidCels);
 }
 
-void PrintSString(CelOutputBuffer out, int x, int y, bool cjustflag, const char *str, text_color col, int val)
+void PrintSString(const CelOutputBuffer &out, int x, int y, bool cjustflag, const char *str, text_color col, int val)
 {
 	int len, width, sx, sy, i, k, s;
 	int xx, yy;
@@ -2357,7 +2357,7 @@ void StartStore(talk_id s)
 	stextflag = s;
 }
 
-void DrawSText(CelOutputBuffer out)
+void DrawSText(const CelOutputBuffer &out)
 {
 	int i;
 
diff --git a/Source/stores.h b/Source/stores.h
index 90ca6e210..37d588061 100644
--- a/Source/stores.h
+++ b/Source/stores.h
@@ -98,12 +98,12 @@ void InitStores();
 int PentSpn2Spin();
 void SetupTownStores();
 void FreeStoreMem();
-void PrintSString(CelOutputBuffer out, int x, int y, bool cjustflag, const char *str, text_color col, int val);
+void PrintSString(const CelOutputBuffer &out, int x, int y, bool cjustflag, const char *str, text_color col, int val);
 void DrawSLine(CelOutputBuffer out, int y);
 void DrawSTextHelp();
 void ClearSText(int s, int e);
 void StartStore(talk_id s);
-void DrawSText(CelOutputBuffer out);
+void DrawSText(const CelOutputBuffer &out);
 void STextESC();
 void STextUp();
 void STextDown();
diff --git a/Source/storm/storm_net.cpp b/Source/storm/storm_net.cpp
index 3a59dc8c9..475c8dc22 100644
--- a/Source/storm/storm_net.cpp
+++ b/Source/storm/storm_net.cpp
@@ -2,6 +2,7 @@
 #ifndef NONET
 #include <mutex>
 #include <thread>
+#include <utility>
 #endif
 
 #include "dvlnet/abstract_net.h"
@@ -239,7 +240,7 @@ std::vector<std::string> DvlNet_GetGamelist()
 
 void DvlNet_SetPassword(std::string pw)
 {
-	dvlnet_inst->setup_password(pw);
+	dvlnet_inst->setup_password(std::move(pw));
 }
 
 } // namespace devilution