OpenTTD slowdown patch

slowdown.patch

diff --git a/src/console_cmds.cpp b/src/console_cmds.cpp
index 748e4ab..3fb4cef 100644
--- a/src/console_cmds.cpp
+++ b/src/console_cmds.cpp
@@ -2051,6 +2051,13 @@ DEF_CONSOLE_CMD(ConFramerateWindow)
 	return true;
 }
 
+DEF_CONSOLE_CMD(ConSetSlowdown)
+{
+	extern uint64 _fake_slowdown;
+	if (argc > 1) _fake_slowdown = atoi(argv[1]) * 1000;
+	return true;
+}
+
 /*******************************
  * console command registration
  *******************************/
@@ -2183,6 +2190,7 @@ void IConsoleStdLibRegister()
 #endif
 	IConsoleCmdRegister("fps",     ConFramerate);
 	IConsoleCmdRegister("fps_wnd", ConFramerateWindow);
+	IConsoleCmdRegister("slowdown", ConSetSlowdown);
 
 	/* NewGRF development stuff */
 	IConsoleCmdRegister("reload_newgrfs",  ConNewGRFReload, ConHookNewGRFDeveloperTool);
diff --git a/src/openttd.cpp b/src/openttd.cpp
index ffd30cf..04310a1 100644
--- a/src/openttd.cpp
+++ b/src/openttd.cpp
@@ -1320,6 +1320,9 @@ static void CheckCaches()
 	}
 }
 
+uint64 _fake_slowdown = 0;
+char _fake_slowdown_buf[100];
+
 /**
  * State controlling game loop.
  * The state must not be changed from anywhere but here.
@@ -1348,6 +1351,11 @@ void StateGameLoop()
 	PerformanceAccumulator::Reset(PFE_GL_LANDSCAPE);
 	if (HasModalProgress()) return;
 
+	for (uint64 slow = 0; slow < _fake_slowdown; slow++) {
+		SetDParam(0, slow);
+		GetString(_fake_slowdown_buf, STR_FRAMERATE_MS_GOOD, lastof(_fake_slowdown_buf));
+	}
+
 	Layouter::ReduceLineCache();
 
 	if (_game_mode == GM_EDITOR) {