add emu.yield, which when used allows a script to run while emulation is paused and interact with the gui/main window in realtime

BizHawk.MultiClient/LuaImplementation.cs

@@ -20,7 +20,7 @@ namespace BizHawk.MultiClient
 		public EventWaitHandle LuaWait;
 		public bool isRunning;
 		private int CurrentMemoryDomain = 0; //Main memory by default
-		//List<Lua> runningThreads = new List<Lua>();
+		public bool FrameAdvanceRequested;
 		Lua currThread;
 
 		public LuaImplementation(LuaConsole passed)
@@ -141,11 +141,20 @@ namespace BizHawk.MultiClient
 			return lua_result;
 		}
 
-		public void ResumeScript(Lua script)
+		public class ResumeResult
+		{
+			public bool WaitForFrame;
+		}
+
+		public ResumeResult ResumeScript(Lua script)
 		{
 			currThread = script;
 			script.Resume(0);
 			currThread = null;
+			var result = new ResumeResult();
+			result.WaitForFrame = FrameAdvanceRequested;
+			FrameAdvanceRequested = false;
+			return result;
 		}
 
 		public void print(string s)
@@ -173,6 +182,7 @@ namespace BizHawk.MultiClient
 		public static string[] EmuFunctions = new string[]
 		{
 			"frameadvance",
+			"yield",
 			"pause",
 			"unpause",
 			"togglepause",
@@ -339,6 +349,12 @@ namespace BizHawk.MultiClient
 		//Emu library
 		//----------------------------------------------------
 		public void emu_frameadvance()
+		{
+			FrameAdvanceRequested = true;
+			currThread.Yield(0);
+		}
+
+		public void emu_yield()
 		{
 			currThread.Yield(0);
 		}

BizHawk.MultiClient/MainForm.cs

@@ -372,6 +372,10 @@ namespace BizHawk.MultiClient
 				Global.AutoFireController.LatchFromPhysical(Global.ControllerInputCoalescer);
 				Global.ClickyVirtualPadController.FrameTick();
 
+#if WINDOWS
+				LuaConsole1.ResumeScripts(false);
+#endif
+
 				StepRunLoop_Core();
 				//if(!IsNullEmulator())
 				StepRunLoop_Throttle();
@@ -1682,11 +1686,9 @@ namespace BizHawk.MultiClient
 			{
 				Global.RenderPanel.ClearGUIText();
 				//client input-related duties
+
 #if WINDOWS
-				//if (LuaConsole1.IsRunning())
-				{
-					LuaConsole1.ResumeScripts();
-				}
+				LuaConsole1.ResumeScripts(true);
 #endif
 
 				runloop_fps++; 

BizHawk.MultiClient/tools/LuaConsole.cs

@@ -725,12 +725,24 @@ namespace BizHawk.MultiClient
 			OpenLuaSession();
 		}
 
-		public void ResumeScripts()
+		/// <summary>
+		/// resumes suspended coroutines
+		/// </summary>
+		/// <param name="includeFrameWaiters">should frame waiters be waken up? only use this immediately before a frame of emulation</param>
+		public void ResumeScripts(bool includeFrameWaiters)
 		{
 			foreach (var s in luaList)
 			{
 				if (s.Enabled && s.Thread != null)
-					LuaImp.ResumeScript(s.Thread);
+				{
+					bool prohibit = false;
+					if (s.FrameWaiting && !includeFrameWaiters)
+						prohibit = true;
+
+					if (prohibit) continue;
+					var result = LuaImp.ResumeScript(s.Thread);
+					s.FrameWaiting = result.WaitForFrame;
+				}
 			}
 		}
 

BizHawk.MultiClient/tools/LuaFiles.cs

@@ -12,12 +12,14 @@ namespace BizHawk.MultiClient
 		public bool Enabled;
 		public bool IsSeparator;
 		public LuaInterface.Lua Thread;
+		public bool FrameWaiting;
 
 		public LuaFile(string path)
 		{
 			Name = "";
 			Path = path;
 			Enabled = true;
+			FrameWaiting = false;
 		}
 
 		public void Stop()