Tastudio - proof of concept for cachine the input state during a screen refresh. A huge speed up here, about 400-500%. Implementation is a bit sloppy but works

BizHawk.Client.Common/movie/tasproj/TasMovie.cs

@@ -133,10 +133,29 @@ namespace BizHawk.Client.Common
 		/// </summary>
 		public string DisplayValue(int frame, string buttonName)
 		{
+			if (UseInputCache && InputStateCache.ContainsKey(frame))
+			{
+				return CreateDisplayValueForButton(InputStateCache[frame], buttonName);
+			}
+
 			var adapter = GetInputState(frame);
+
+			if (UseInputCache)
+			{
+				InputStateCache.Add(frame, adapter);
+			}
+
 			return CreateDisplayValueForButton(adapter, buttonName);
 		}
 
+		private readonly Dictionary<int, IController> InputStateCache = new Dictionary<int, IController>();
+
+		public bool UseInputCache { get; set; }
+		public void FlushInputCache()
+		{
+			InputStateCache.Clear();
+		}
+
 		public string CreateDisplayValueForButton(IController adapter, string buttonName)
 		{
 			if (adapter.Type.BoolButtons.Contains(buttonName))

BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.cs

@@ -153,9 +153,15 @@ namespace BizHawk.Client.EmuHawk
 
 		public void RefreshDialog()
 		{
+			_currentTasMovie.FlushInputCache();
+			_currentTasMovie.UseInputCache = true;
+
 			TasView.ItemCount = _currentTasMovie.InputLogLength + 1;
 			TasView.Refresh();
 
+			_currentTasMovie.FlushInputCache();
+			_currentTasMovie.UseInputCache = false;
+
 			if (MarkerControl != null)
 			{
 				MarkerControl.UpdateValues();