Lua - implement emu.displayvsync, also add on screen message when limit frame rate is toggled

BizHawk.MultiClient/LuaImplementation.cs

@@ -290,6 +290,7 @@ namespace BizHawk.MultiClient
 			"frameskip",
 			"minimizeframeskip",
 			"limitframerate",
+			"displayvsync",
 		};
 
 		public static string[] MemoryFunctions = new string[]
@@ -880,6 +881,23 @@ namespace BizHawk.MultiClient
 			}
 		}
 
+		public void emu_displayvsync(object boolean)
+		{
+			string temp = boolean.ToString();
+			if (!String.IsNullOrWhiteSpace(temp))
+			{
+				if (temp == "0" || temp.ToLower() == "false")
+				{
+					Global.Config.DisplayVSync = false;
+				}
+				else
+				{
+					Global.Config.DisplayVSync = true;
+				}
+				Global.MainForm.VsyncMessage();
+			}
+		}
+
 		public void emu_frameskip(object num_frames)
 		{
 			try

BizHawk.MultiClient/MainForm.MenuItems.cs

@@ -72,6 +72,19 @@ namespace BizHawk.MultiClient
 		{
 			Global.Config.DisplayVSync ^= true;
 			Global.RenderPanel.Resized = true;
+			VsyncMessage();
+		}
+
+		public void VsyncMessage()
+		{
+			if (Global.Config.DisplayVSync)
+			{
+				Global.OSD.AddMessage("Display Vsync is set to on");
+			}
+			else
+			{
+				Global.OSD.AddMessage("Display Vsync is set to off");
+			}
 		}
 
 		private void miAutoMinimizeSkipping_Click(object sender, EventArgs e)