Migrate Singletons to ExplicitSingleton

2025-08-11 02:43:58 +02:00 · 2023-01-19 19:43:33 +01:00
parent 8680f0d4a7
commit 3cb6b26d1d
9 changed files with 140 additions and 122 deletions
--- a/src/PowderToyFontEditor.cpp
+++ b/src/PowderToyFontEditor.cpp
@@ -17,6 +17,8 @@
 #include "client/GameSave.h"
 #include "client/SaveFile.h"

+#include "common/Platform.h"
+#include "common/tpt-rand.h"
 #include "gui/game/GameController.h"
 #include "gui/game/GameView.h"
 #include "gui/font/FontEditor.h"
@@ -409,8 +411,34 @@ void EngineProcess()
 	}
 }

+struct ExplicitSingletons
+{
+	// These need to be listed in the order they are populated in main.
+	std::unique_ptr<RNG> rng;
+	std::unique_ptr<ui::Engine> engine;
+};
+static std::unique_ptr<ExplicitSingletons> explicitSingletons;
+
 int main(int argc, char * argv[])
 {
+	Platform::SetupCrt();
+	atexit([]() {
+		ui::Engine::Ref().CloseWindow();
+		explicitSingletons.reset();
+		if (SDL_GetWindowFlags(sdl_window) & SDL_WINDOW_OPENGL)
+		{
+			// * nvidia-460 egl registers callbacks with x11 that end up being called
+			//   after egl is unloaded unless we grab it here and release it after
+			//   sdl closes the display. this is an nvidia driver weirdness but
+			//   technically an sdl bug. glfw has this fixed:
+			//   https://github.com/glfw/glfw/commit/9e6c0c747be838d1f3dc38c2924a47a42416c081
+			SDL_GL_LoadLibrary(NULL);
+			SDL_QuitSubSystem(SDL_INIT_VIDEO);
+			SDL_GL_UnloadLibrary();
+		}
+		SDL_Quit();
+	});
+	explicitSingletons = std::make_unique<ExplicitSingletons>();
 	currentWidth = WINDOWW;
 	currentHeight = WINDOWH;
 	
@@ -433,6 +461,9 @@ int main(int argc, char * argv[])
 	if(scale < 1 || scale > 10)
 		scale = 1;

+	explicitSingletons->rng = std::make_unique<RNG>();
+	explicitSingletons->engine = std::make_unique<ui::Engine>();
+
 	SDLOpen();

 	StopTextInput();
@@ -449,8 +480,6 @@ int main(int argc, char * argv[])
 	engine->Begin(WINDOWW, WINDOWH);
 	engine->SetFastQuit(true);

-	GameController * gameController = NULL;
-
 	if (argc >= 2)
 	{
 		engine->ShowWindow(new FontEditor(argv[1]));
@@ -462,20 +491,5 @@ int main(int argc, char * argv[])
 	}

 	EngineProcess();
-	ui::Engine::Ref().CloseWindow();
-	delete gameController;
-	delete ui::Engine::Ref().g;
-	if (SDL_GetWindowFlags(sdl_window) & SDL_WINDOW_OPENGL)
-	{
-		// * nvidia-460 egl registers callbacks with x11 that end up being called
-		//   after egl is unloaded unless we grab it here and release it after
-		//   sdl closes the display. this is an nvidia driver weirdness but
-		//   technically an sdl bug. glfw has this fixed:
-		//   https://github.com/glfw/glfw/commit/9e6c0c747be838d1f3dc38c2924a47a42416c081
-		SDL_GL_LoadLibrary(NULL);
-		SDL_QuitSubSystem(SDL_INIT_VIDEO);
-		SDL_GL_UnloadLibrary();
-	}
-	SDL_Quit();
 	return 0;
 }
--- a/src/PowderToyRenderer.cpp
+++ b/src/PowderToyRenderer.cpp
@@ -8,6 +8,7 @@
 #include <vector>

 #include "common/String.h"
+#include "common/tpt-rand.h"
 #include "Format.h"
 #include "gui/interface/Engine.h"

@@ -64,6 +65,7 @@ int main(int argc, char *argv[])
 			throw e;
 	}

+	auto rng = std::make_unique<RNG>();
 	Simulation * sim = new Simulation();
 	Renderer * ren = new Renderer(new Graphics(), sim);

--- a/src/PowderToySDL.cpp
+++ b/src/PowderToySDL.cpp
@@ -28,6 +28,9 @@
 #include "client/http/RequestManager.h"
 #include "common/Platform.h"
 #include "graphics/Graphics.h"
+#include "simulation/SaveRenderer.h"
+#include "common/tpt-rand.h"
+#include "gui/game/Favorite.h"
 #include "gui/Style.h"

 #include "gui/game/GameController.h"
@@ -277,7 +280,6 @@ int elapsedTime = 0, currentTime = 0, lastTime = 0, currentFrame = 0;
 uint64_t lastTick = 0;
 uint64_t lastFpsUpdate = 0;
 float fps = 0;
-ui::Engine * engine = NULL;
 bool showLargeScreenDialog = false;
 float currentWidth, currentHeight;

@@ -290,11 +292,12 @@ bool hasMouseMoved = false;

 void EventProcess(SDL_Event event)
 {
+	auto &engine = ui::Engine::Ref();
 	switch (event.type)
 	{
 	case SDL_QUIT:
-		if (engine->GetFastQuit() || engine->CloseWindow())
-			engine->Exit();
+		if (engine.GetFastQuit() || engine.CloseWindow())
+			engine.Exit();
 		break;
 	case SDL_KEYDOWN:
 		if (SDL_GetModState() & KMOD_GUI)
@@ -302,30 +305,30 @@ void EventProcess(SDL_Event event)
 			break;
 		}
 		if (!event.key.repeat && event.key.keysym.sym == 'q' && (event.key.keysym.mod&KMOD_CTRL))
-			engine->ConfirmExit();
+			engine.ConfirmExit();
 		else
-			engine->onKeyPress(event.key.keysym.sym, event.key.keysym.scancode, event.key.repeat, event.key.keysym.mod&KMOD_SHIFT, event.key.keysym.mod&KMOD_CTRL, event.key.keysym.mod&KMOD_ALT);
+			engine.onKeyPress(event.key.keysym.sym, event.key.keysym.scancode, event.key.repeat, event.key.keysym.mod&KMOD_SHIFT, event.key.keysym.mod&KMOD_CTRL, event.key.keysym.mod&KMOD_ALT);
 		break;
 	case SDL_KEYUP:
 		if (SDL_GetModState() & KMOD_GUI)
 		{
 			break;
 		}
-		engine->onKeyRelease(event.key.keysym.sym, event.key.keysym.scancode, event.key.repeat, event.key.keysym.mod&KMOD_SHIFT, event.key.keysym.mod&KMOD_CTRL, event.key.keysym.mod&KMOD_ALT);
+		engine.onKeyRelease(event.key.keysym.sym, event.key.keysym.scancode, event.key.repeat, event.key.keysym.mod&KMOD_SHIFT, event.key.keysym.mod&KMOD_CTRL, event.key.keysym.mod&KMOD_ALT);
 		break;
 	case SDL_TEXTINPUT:
 		if (SDL_GetModState() & KMOD_GUI)
 		{
 			break;
 		}
-		engine->onTextInput(ByteString(event.text.text).FromUtf8());
+		engine.onTextInput(ByteString(event.text.text).FromUtf8());
 		break;
 	case SDL_TEXTEDITING:
 		if (SDL_GetModState() & KMOD_GUI)
 		{
 			break;
 		}
-		engine->onTextEditing(ByteString(event.edit.text).FromUtf8(), event.edit.start);
+		engine.onTextEditing(ByteString(event.edit.text).FromUtf8(), event.edit.start);
 		break;
 	case SDL_MOUSEWHEEL:
 	{
@@ -337,18 +340,18 @@ void EventProcess(SDL_Event event)
 			y *= -1;
 		}

-		engine->onMouseWheel(mousex, mousey, y); // TODO: pass x?
+		engine.onMouseWheel(mousex, mousey, y); // TODO: pass x?
 		break;
 	}
 	case SDL_MOUSEMOTION:
 		mousex = event.motion.x;
 		mousey = event.motion.y;
-		engine->onMouseMove(mousex, mousey);
+		engine.onMouseMove(mousex, mousey);

 		hasMouseMoved = true;
 		break;
 	case SDL_DROPFILE:
-		engine->onFileDrop(event.drop.file);
+		engine.onFileDrop(event.drop.file);
 		SDL_free(event.drop.file);
 		break;
 	case SDL_MOUSEBUTTONDOWN:
@@ -359,7 +362,7 @@ void EventProcess(SDL_Event event)
 			mousey = event.button.y;
 		}
 		mouseButton = event.button.button;
-		engine->onMouseClick(mousex, mousey, mouseButton);
+		engine.onMouseClick(mousex, mousey, mouseButton);

 		mouseDown = true;
 		if constexpr (!DEBUG)
@@ -375,7 +378,7 @@ void EventProcess(SDL_Event event)
 			mousey = event.button.y;
 		}
 		mouseButton = event.button.button;
-		engine->onMouseUnclick(mousex, mousey, mouseButton);
+		engine.onMouseUnclick(mousex, mousey, mouseButton);

 		mouseDown = false;
 		if constexpr (!DEBUG)
@@ -392,8 +395,8 @@ void EventProcess(SDL_Event event)
 			{
 				//initial mouse coords, sdl won't tell us this if mouse hasn't moved
 				CalculateMousePosition(&mousex, &mousey);
-				engine->initialMouse(mousex, mousey);
-				engine->onMouseMove(mousex, mousey);
+				engine.initialMouse(mousex, mousey);
+				engine.onMouseMove(mousex, mousey);
 				calculatedInitialMouse = true;
 			}
 			break;
@@ -421,7 +424,7 @@ void EventProcess(SDL_Event event)
 			if (mouseDown)
 			{
 				mouseDown = false;
-				engine->onMouseUnclick(mousex, mousey, mouseButton);
+				engine.onMouseUnclick(mousex, mousey, mouseButton);
 			}
 			break;*/
 		}
@@ -439,7 +442,7 @@ void LargeScreenDialog()
 	if (!ConfirmPrompt::Blocking("Large screen detected", message.Build()))
 	{
 		GlobalPrefs::Ref().Set("Scale", 1);
-		engine->SetScale(1);
+		ui::Engine::Ref().SetScale(1);
 	}
 }

@@ -451,34 +454,35 @@ void EngineProcess()
 	uint64_t drawingTimer = 0;
 	auto frameStart = uint64_t(SDL_GetTicks()) * UINT64_C(1'000'000);

-	while(engine->Running())
+	auto &engine = ui::Engine::Ref();
+	while(engine.Running())
 	{
-		if(engine->Broken()) { engine->UnBreak(); break; }
+		if(engine.Broken()) { engine.UnBreak(); break; }
 		event.type = 0;
 		while (SDL_PollEvent(&event))
 		{
 			EventProcess(event);
 			event.type = 0; //Clear last event
 		}
-		if(engine->Broken()) { engine->UnBreak(); break; }
+		if(engine.Broken()) { engine.UnBreak(); break; }

-		engine->Tick();
+		engine.Tick();

 		int drawcap = ui::Engine::Ref().GetDrawingFrequencyLimit();
 		if (!drawcap || drawingTimer > 1e9f / drawcap)
 		{
-			engine->Draw();
+			engine.Draw();
 			drawingTimer = 0;

-			if (scale != engine->Scale || fullscreen != engine->Fullscreen ||
-					altFullscreen != engine->GetAltFullscreen() ||
-					forceIntegerScaling != engine->GetForceIntegerScaling() || resizable != engine->GetResizable())
+			if (scale != engine.Scale || fullscreen != engine.Fullscreen ||
+					altFullscreen != engine.GetAltFullscreen() ||
+					forceIntegerScaling != engine.GetForceIntegerScaling() || resizable != engine.GetResizable())
 			{
-				SDLSetScreen(engine->Scale, engine->GetResizable(), engine->Fullscreen, engine->GetAltFullscreen(),
-							 engine->GetForceIntegerScaling());
+				SDLSetScreen(engine.Scale, engine.GetResizable(), engine.Fullscreen, engine.GetAltFullscreen(),
+							 engine.GetForceIntegerScaling());
 			}

-			blit(engine->g->vid);
+			blit(engine.g->vid);
 		}
 		auto fpsLimit = ui::Engine::Ref().FpsLimit;
 		auto now = uint64_t(SDL_GetTicks()) * UINT64_C(1'000'000);
@@ -497,7 +501,7 @@ void EngineProcess()
 		correctedFrameTimeAvg = correctedFrameTimeAvg + (correctedFrameTime - correctedFrameTimeAvg) * 0.05;
 		if (frameStart - lastFpsUpdate > UINT64_C(200'000'000))
 		{
-			engine->SetFps(1e9f / correctedFrameTimeAvg);
+			engine.SetFps(1e9f / correctedFrameTimeAvg);
 			lastFpsUpdate = frameStart;
 		}
 		if (frameStart - lastTick > UINT64_C(100'000'000))
@@ -519,8 +523,8 @@ void EngineProcess()

 void BlueScreen(String detailMessage)
 {
-	ui::Engine * engine = &ui::Engine::Ref();
-	engine->g->fillrect(0, 0, engine->GetWidth(), engine->GetHeight(), 17, 114, 169, 210);
+	auto &engine = ui::Engine::Ref();
+	engine.g->fillrect(0, 0, engine.GetWidth(), engine.GetHeight(), 17, 114, 169, 210);

 	String errorTitle = "ERROR";
 	String errorDetails = "Details: " + detailMessage;
@@ -529,15 +533,15 @@ void BlueScreen(String detailMessage)
 	int errorWidth = 0;
 	Graphics::textsize(errorHelp, errorWidth, height);

-	engine->g->drawtext((engine->GetWidth()/2)-(errorWidth/2), ((engine->GetHeight()/2)-100) + currentY, errorTitle.c_str(), 255, 255, 255, 255);
+	engine.g->drawtext((engine.GetWidth()/2)-(errorWidth/2), ((engine.GetHeight()/2)-100) + currentY, errorTitle.c_str(), 255, 255, 255, 255);
 	Graphics::textsize(errorTitle, width, height);
 	currentY += height + 4;

-	engine->g->drawtext((engine->GetWidth()/2)-(errorWidth/2), ((engine->GetHeight()/2)-100) + currentY, errorDetails.c_str(), 255, 255, 255, 255);
+	engine.g->drawtext((engine.GetWidth()/2)-(errorWidth/2), ((engine.GetHeight()/2)-100) + currentY, errorDetails.c_str(), 255, 255, 255, 255);
 	Graphics::textsize(errorTitle, width, height);
 	currentY += height + 4;

-	engine->g->drawtext((engine->GetWidth()/2)-(errorWidth/2), ((engine->GetHeight()/2)-100) + currentY, errorHelp.c_str(), 255, 255, 255, 255);
+	engine.g->drawtext((engine.GetWidth()/2)-(errorWidth/2), ((engine.GetHeight()/2)-100) + currentY, errorHelp.c_str(), 255, 255, 255, 255);
 	Graphics::textsize(errorTitle, width, height);
 	currentY += height + 4;

@@ -548,7 +552,7 @@ void BlueScreen(String detailMessage)
 		while (SDL_PollEvent(&event))
 			if(event.type == SDL_QUIT)
 				exit(-1);
-		blit(engine->g->vid);
+		blit(engine.g->vid);
 	}
 }

@@ -592,8 +596,13 @@ struct ExplicitSingletons
 {
 	// These need to be listed in the order they are populated in main.
 	std::unique_ptr<GlobalPrefs> globalPrefs;
-	std::unique_ptr<Client> client;
 	http::RequestManagerPtr requestManager;
+	std::unique_ptr<Client> client;
+	std::unique_ptr<SaveRenderer> saveRenderer;
+	std::unique_ptr<RNG> rng;
+	std::unique_ptr<Favorite> favorite;
+	std::unique_ptr<ui::Engine> engine;
+	std::unique_ptr<GameController> gameController;
 };
 static std::unique_ptr<ExplicitSingletons> explicitSingletons;

@@ -601,7 +610,20 @@ int main(int argc, char * argv[])
 {
 	Platform::SetupCrt();
 	atexit([]() {
+		ui::Engine::Ref().CloseWindow();
 		explicitSingletons.reset();
+		if (SDL_GetWindowFlags(sdl_window) & SDL_WINDOW_OPENGL)
+		{
+			// * nvidia-460 egl registers callbacks with x11 that end up being called
+			//   after egl is unloaded unless we grab it here and release it after
+			//   sdl closes the display. this is an nvidia driver weirdness but
+			//   technically an sdl bug. glfw has this fixed:
+			//   https://github.com/glfw/glfw/commit/9e6c0c747be838d1f3dc38c2924a47a42416c081
+			SDL_GL_LoadLibrary(NULL);
+			SDL_QuitSubSystem(SDL_INIT_VIDEO);
+			SDL_GL_UnloadLibrary();
+		}
+		SDL_Quit();
 	});
 	explicitSingletons = std::make_unique<ExplicitSingletons>();
 	currentWidth = WINDOWW;
@@ -769,6 +791,11 @@ int main(int argc, char * argv[])
 	explicitSingletons->client = std::make_unique<Client>();
 	Client::Ref().Initialize();

+	explicitSingletons->saveRenderer = std::make_unique<SaveRenderer>();
+	explicitSingletons->rng = std::make_unique<RNG>();
+	explicitSingletons->favorite = std::make_unique<Favorite>();
+	explicitSingletons->engine = std::make_unique<ui::Engine>();
+
 	// TODO: maybe bind the maximum allowed scale to screen size somehow
 	if(scale < 1 || scale > SCALE_MAXIMUM)
 		scale = 1;
@@ -788,19 +815,18 @@ int main(int argc, char * argv[])

 	StopTextInput();

-	ui::Engine::Ref().g = new Graphics();
-	ui::Engine::Ref().Scale = scale;
-	ui::Engine::Ref().SetResizable(resizable);
-	ui::Engine::Ref().Fullscreen = fullscreen;
-	ui::Engine::Ref().SetAltFullscreen(altFullscreen);
-	ui::Engine::Ref().SetForceIntegerScaling(forceIntegerScaling);
-	ui::Engine::Ref().MomentumScroll = momentumScroll;
-	ui::Engine::Ref().ShowAvatars = showAvatars;
-
-	engine = &ui::Engine::Ref();
-	engine->SetMaxSize(desktopWidth, desktopHeight);
-	engine->Begin(WINDOWW, WINDOWH);
-	engine->SetFastQuit(prefs.Get("FastQuit", true));
+	auto &engine = ui::Engine::Ref();
+	engine.g = new Graphics();
+	engine.Scale = scale;
+	engine.SetResizable(resizable);
+	engine.Fullscreen = fullscreen;
+	engine.SetAltFullscreen(altFullscreen);
+	engine.SetForceIntegerScaling(forceIntegerScaling);
+	engine.MomentumScroll = momentumScroll;
+	engine.ShowAvatars = showAvatars;
+	engine.SetMaxSize(desktopWidth, desktopHeight);
+	engine.Begin(WINDOWW, WINDOWH);
+	engine.SetFastQuit(prefs.Get("FastQuit", true));

 	bool enableBluescreen = !DEBUG && !true_arg(arguments["disable-bluescreen"]);
 	if (enableBluescreen)
@@ -817,11 +843,10 @@ int main(int argc, char * argv[])
 		X86KillDenormals();
 	}

-	GameController * gameController = NULL;
-
 	auto wrapWithBluescreen = [&]() {
-		gameController = new GameController();
-		engine->ShowWindow(gameController->GetView());
+		explicitSingletons->gameController = std::make_unique<GameController>();
+		auto *gameController = explicitSingletons->gameController.get();
+		engine.ShowWindow(gameController->GetView());

 		auto openArg = arguments["open"];
 		if (openArg.has_value())
@@ -863,12 +888,12 @@ int main(int argc, char * argv[])
 		auto ptsaveArg = arguments["ptsave"];
 		if (ptsaveArg.has_value())
 		{
-			engine->g->Clear();
-			engine->g->fillrect((engine->GetWidth()/2)-101, (engine->GetHeight()/2)-26, 202, 52, 0, 0, 0, 210);
-			engine->g->drawrect((engine->GetWidth()/2)-100, (engine->GetHeight()/2)-25, 200, 50, 255, 255, 255, 180);
-			engine->g->drawtext((engine->GetWidth()/2)-(Graphics::textwidth("Loading save...")/2), (engine->GetHeight()/2)-5, "Loading save...", style::Colour::InformationTitle.Red, style::Colour::InformationTitle.Green, style::Colour::InformationTitle.Blue, 255);
+			engine.g->Clear();
+			engine.g->fillrect((engine.GetWidth()/2)-101, (engine.GetHeight()/2)-26, 202, 52, 0, 0, 0, 210);
+			engine.g->drawrect((engine.GetWidth()/2)-100, (engine.GetHeight()/2)-25, 200, 50, 255, 255, 255, 180);
+			engine.g->drawtext((engine.GetWidth()/2)-(Graphics::textwidth("Loading save...")/2), (engine.GetHeight()/2)-5, "Loading save...", style::Colour::InformationTitle.Red, style::Colour::InformationTitle.Green, style::Colour::InformationTitle.Blue, 255);

-			blit(engine->g->vid);
+			blit(engine.g->vid);
 			try
 			{
 				ByteString saveIdPart;
@@ -926,21 +951,5 @@ int main(int argc, char * argv[])
 	{
 		wrapWithBluescreen();
 	}
-
-	ui::Engine::Ref().CloseWindow();
-	delete gameController;
-	delete ui::Engine::Ref().g;
-	if (SDL_GetWindowFlags(sdl_window) & SDL_WINDOW_OPENGL)
-	{
-		// * nvidia-460 egl registers callbacks with x11 that end up being called
-		//   after egl is unloaded unless we grab it here and release it after
-		//   sdl closes the display. this is an nvidia driver weirdness but
-		//   technically an sdl bug. glfw has this fixed:
-		//   https://github.com/glfw/glfw/commit/9e6c0c747be838d1f3dc38c2924a47a42416c081
-		SDL_GL_LoadLibrary(NULL);
-		SDL_QuitSubSystem(SDL_INIT_VIDEO);
-		SDL_GL_UnloadLibrary();
-	}
-	SDL_Quit();
 	return 0;
 }
--- a/src/common/Singleton.h
+++ b/src/common/Singleton.h
@@ -1,12 +0,0 @@
-#pragma once
-
-template<typename T>
-class Singleton
-{
-public:
-	static T& Ref()
-	{
-		static T instance;
-		return instance;
-	}
-};
--- a/src/common/tpt-rand.cpp
+++ b/src/common/tpt-rand.cpp
@@ -9,7 +9,7 @@ static inline uint64_t rotl(const uint64_t x, int k)
 	return (x << k) | (x >> (64 - k));
 }

-uint64_t RNG::next()
+uint64_t RNGType::next()
 {
 	const uint64_t s0 = s[0];
 	uint64_t s1 = s[1];
@@ -22,44 +22,44 @@ uint64_t RNG::next()
 	return result;
 }

-unsigned int RNG::gen()
+unsigned int RNGType::gen()
 {
 	return next() & 0x7FFFFFFF;
 }

-unsigned int RNG::operator()()
+unsigned int RNGType::operator()()
 {
 	return next()&0xFFFFFFFF;
 }

-int RNG::between(int lower, int upper)
+int RNGType::between(int lower, int upper)
 {
 	unsigned int r = next();
 	return static_cast<int>(r % (upper - lower + 1)) + lower;
 }

-bool RNG::chance(int nominator, unsigned int denominator)
+bool RNGType::chance(int nominator, unsigned int denominator)
 {
 	if (nominator < 0)
 		return false;
 	return next() % denominator < static_cast<unsigned int>(nominator);
 }

-float RNG::uniform01()
+float RNGType::uniform01()
 {
 	return static_cast<float>(next()&0xFFFFFFFF)/(float)0xFFFFFFFF;
 }

-RNG::RNG()
+RNGType::RNGType()
 {
 	s[0] = time(NULL);
 	s[1] = 614;
 }

-void RNG::seed(unsigned int sd)
+void RNGType::seed(unsigned int sd)
 {
 	s[0] = sd;
 	s[1] = sd;
 }

-RNG random_gen;
+RNGType random_gen;
--- a/src/common/tpt-rand.h
+++ b/src/common/tpt-rand.h
@@ -2,9 +2,9 @@
 #include "Config.h"

 #include <stdint.h>
-#include "Singleton.h"
+#include "ExplicitSingleton.h"

-class RNG : public Singleton<RNG>
+class RNGType
 {
 private:
 	uint64_t s[2];
@@ -16,8 +16,13 @@ public:
 	bool chance(int nominator, unsigned int denominator);
 	float uniform01();

-	RNG();
+	RNGType();
 	void seed(unsigned int sd);
 };

-extern RNG random_gen;
+// Needed because we also have random_gen, and that would take the singleton role if RNGType had an ExplicitSingleton base.
+class RNG : public RNGType, public ExplicitSingleton<RNG>
+{
+};
+
+extern RNGType random_gen;
--- a/src/gui/game/Favorite.h
+++ b/src/gui/game/Favorite.h
@@ -4,9 +4,9 @@
 #include "common/String.h"
 #include <vector>

-#include "common/Singleton.h"
+#include "common/ExplicitSingleton.h"

-class Favorite : public Singleton<Favorite>
+class Favorite : public ExplicitSingleton<Favorite>
 {
 	std::vector<ByteString> favoritesList;
 public:
--- a/src/gui/interface/Engine.h
+++ b/src/gui/interface/Engine.h
@@ -2,7 +2,7 @@

 #include <stack>
 #include "common/String.h"
-#include "common/Singleton.h"
+#include "common/ExplicitSingleton.h"
 #include "graphics/Pixel.h"
 #include "gui/interface/Point.h"

@@ -16,7 +16,7 @@ namespace ui
 	 * Controls the User Interface.
 	 * Send user inputs to the Engine and the appropriate controls and components will interact.
 	 */
-	class Engine: public Singleton<Engine>
+	class Engine: public ExplicitSingleton<Engine>
 	{
 	public:
 		Engine();
--- a/src/simulation/SaveRenderer.h
+++ b/src/simulation/SaveRenderer.h
@@ -1,6 +1,6 @@
 #pragma once
 #include "Config.h"
-#include "common/Singleton.h"
+#include "common/ExplicitSingleton.h"
 #include <mutex>

 class GameSave;
@@ -9,7 +9,7 @@ class Graphics;
 class Simulation;
 class Renderer;

-class SaveRenderer: public Singleton<SaveRenderer> {
+class SaveRenderer: public ExplicitSingleton<SaveRenderer> {
 	Graphics * g;
 	Simulation * sim;
 	Renderer * ren;