Significantly improved performance by adding caching of combinational chips

Assets/Scripts/Description/Types/ChipDescription.cs

@@ -14,6 +14,7 @@ public class ChipDescription
 		public string Name;
 		public NameDisplayLocation NameLocation;
 		public ChipType ChipType;
+		public bool ShouldBeCached;
 		public Vector2 Size;
 		public Color Colour;
 		public PinDescription[] InputPins;

Assets/Scripts/Game/Project/DevChipInstance.cs

@@ -212,6 +212,9 @@ public void NotifySaved(ChipDescription savedDescription)
 			LastSavedDescription = savedDescription;
 
 			RegenerateParentChipNamesHash();
+
+			Simulator.combinationalChipCaches.Remove(savedDescription.Name);
+			Simulator.chipsKnowToNotBeCombinational.Remove(savedDescription.Name);
 		}
 
 		public void AddNewSubChip(SubChipInstance subChip, bool isLoading)
@@ -228,7 +231,7 @@ public void AddNewDevPin(DevPinInstance pin, bool isLoadingFromFile)
 			AddElement(pin);
 			if (!isLoadingFromFile)
 			{
-				Simulator.AddPin(SimChip, pin.ID, pin.IsInputPin);
+				Simulator.AddPin(SimChip, pin.ID, pin.IsInputPin, pin.BitCount);
 			}
 		}
 

Assets/Scripts/Game/Project/Project.cs

@@ -122,6 +122,9 @@ public void EnterViewMode(SubChipInstance subchip)
 		{
 			if (chipLibrary.TryGetChipDescription(subchip.Description.Name, out ChipDescription description))
 			{
+				Simulator.useCaching = false; // Disable caching while viewing so subchips actually show what they are doing
+				Simulator.isCreatingACache = false; // Cancel any cache creation that might be going on
+
 				SimChip simChipToView = ViewedChip.SimChip.GetSubChipFromID(subchip.ID);
 
 				DevChipInstance viewChip = DevChipInstance.LoadFromDescriptionTest(description, chipLibrary).devChip;
@@ -140,6 +143,8 @@ public void ReturnToPreviousViewedChip()
 				chipViewStack.Pop();
 				controller.CancelEverything();
 				UpdateViewedChipsString();
+
+				if (chipViewStack.Count == 1) Simulator.useCaching = true; // Left View mode, so turn caching back on
 			}
 		}
 

Assets/Scripts/Graphics/UI/Menus/BottomBarUI.cs

@@ -13,7 +13,7 @@ public static class BottomBarUI
 	{
 		public const float barHeight = 3;
 		const float padY = 0.3f;
-		const float buttonSpacing = 0.25f;
+		public const float buttonSpacing = 0.25f;
 		const float buttonHeight = barHeight - padY * 2;
 
 		const string shortcutTextCol = "<color=#666666ff>";

Assets/Scripts/Graphics/UI/Menus/ChipCustomizationMenu.cs

@@ -3,6 +3,7 @@
 using System.Linq;
 using DLS.Description;
 using DLS.Game;
+using DLS.Simulation;
 using Seb.Helpers;
 using Seb.Vis;
 using Seb.Vis.UI;
@@ -19,6 +20,7 @@ public static class ChipCustomizationMenu
 			"Name: Hidden"
 		};
 
+		static readonly string[] cachingOptions = { "Caching: Off", "Caching: On" };
 
 		// ---- State ----
 		static SubChipInstance[] subChipsWithDisplays;
@@ -29,6 +31,7 @@ public static class ChipCustomizationMenu
 		static readonly UIHandle ID_ColourPicker = new("CustomizeMenu_ChipCol");
 		static readonly UIHandle ID_ColourHexInput = new("CustomizeMenu_ChipColHexInput");
 		static readonly UIHandle ID_NameDisplayOptions = new("CustomizeMenu_NameDisplayOptions");
+		static readonly UIHandle ID_CachingOptions = new("CustomizeMenu_CachingOptions");
 		static readonly UI.ScrollViewDrawElementFunc drawDisplayScrollEntry = DrawDisplayScroll;
 		static readonly Func<string, bool> hexStringInputValidator = ValidateHexStringInput;
 
@@ -78,6 +81,40 @@ public static void DrawMenu()
 				UpdateChipColFromHexString(hexColInput.text);
 			}
 
+			// ---- Chip caching UI ----
+			UI.DrawText("Chip Caching:", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeDefault, NextPos(1), Anchor.TopLeft, Color.white);
+			SimChip chip = Project.ActiveProject.ViewedChip.SimChip;
+			if (chip.IsCombinational())
+			{
+				int numberOfInputBits = chip.CalculateNumberOfInputBits();
+				if (numberOfInputBits <= Simulator.MAX_NUM_INPUT_BITS_WHEN_AUTO_CACHING)
+				{
+					UI.DrawText("This chip is being cached.", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+				}
+				else if (numberOfInputBits <= Simulator.MAX_NUM_INPUT_BITS_WHEN_USER_CACHING)
+				{
+					int shouldBeCachedNum = UI.WheelSelector(ID_CachingOptions, cachingOptions, NextPos(), new Vector2(pw, DrawSettings.ButtonHeight), theme.OptionsWheel, Anchor.TopLeft);
+					bool shouldBeCached = false;
+					if (shouldBeCachedNum == 1) shouldBeCached = true;
+					ChipSaveMenu.ActiveCustomizeDescription.ShouldBeCached = shouldBeCached;
+					UI.DrawText("WARNING: Caching chips with many", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+					UI.DrawText("input bits significantly", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+					UI.DrawText("increases the time required to", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+					UI.DrawText("create the cache and may also", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+					UI.DrawText("increase memory consumption!", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+				}
+				else
+				{
+					UI.DrawText("This chip has too many input", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+					UI.DrawText("bits to be cached.", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+				}
+			}
+			else
+			{
+				UI.DrawText("Non-combinational chips", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+				UI.DrawText("can not be cached.", UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeSmall, NextPos(), Anchor.TopLeft, Color.white);
+			}
+
 			// ---- Displays UI ----
 			Color labelCol = ColHelper.Darken(theme.MenuPanelCol, 0.01f);
 			Vector2 labelPos = NextPos(1);
@@ -151,6 +188,13 @@ static void InitUIFromChipDescription()
 			// Init name display mode
 			WheelSelectorState nameDisplayWheelState = UI.GetWheelSelectorState(ID_NameDisplayOptions);
 			nameDisplayWheelState.index = (int)ChipSaveMenu.ActiveCustomizeDescription.NameLocation;
+
+			// Init cache setting
+			WheelSelectorState cacheSettingWheelState = UI.GetWheelSelectorState(ID_CachingOptions);
+			bool cacheBool = ChipSaveMenu.ActiveCustomizeDescription.ShouldBeCached;
+			int cacheInt = 0;
+			if (cacheBool) cacheInt = 1;
+			cacheSettingWheelState.index = cacheInt;
 		}
 
 		static void UpdateCustomizeDescription()

Assets/Scripts/Graphics/UI/Menus/CreateCacheUI.cs

@@ -0,0 +1,20 @@
+using DLS.Simulation;
+using Seb.Helpers;
+using Seb.Vis;
+using Seb.Vis.UI;
+using UnityEngine;
+
+namespace DLS.Graphics
+{
+	public static class CreateCacheUI
+	{
+		public static void DrawCreatingCacheInfo()
+		{
+			string chipName = Simulator.nameOfChipWhoseCacheIsBeingCreated;
+			int percentage = (int)(Simulator.cacheCreatingProgress * 100);
+			string text = $"Creating Cache ({percentage}%): {chipName}";
+			Vector2 textSize = UI.CalculateTextSize(text, UIThemeLibrary.FontSizeDefault, UIThemeLibrary.DefaultFont);
+			UI.TextWithBackground(new Vector2(BottomBarUI.buttonSpacing, BottomBarUI.barHeight + BottomBarUI.buttonSpacing), new Vector2(textSize.x + 1, textSize.y + 1), Anchor.BottomLeft, text, UIThemeLibrary.DefaultFont, UIThemeLibrary.FontSizeDefault, Color.yellow, ColHelper.MakeCol255(40));
+		}
+	}
+}

Assets/Scripts/Graphics/UI/UIDrawer.cs

@@ -1,4 +1,5 @@
 using DLS.Game;
+using DLS.Simulation;
 using Seb.Vis.UI;
 
 namespace DLS.Graphics
@@ -57,6 +58,7 @@ static void DrawProjectMenus(Project project)
 
 			if (menuToDraw != MenuType.ChipCustomization) BottomBarUI.DrawUI(project);
 
+			bool aMenuIsOpen = true;
 			if (menuToDraw == MenuType.ChipSave) ChipSaveMenu.DrawMenu();
 			else if (menuToDraw == MenuType.ChipLibrary) ChipLibraryMenu.DrawMenu();
 			else if (menuToDraw == MenuType.ChipCustomization) ChipCustomizationMenu.DrawMenu();
@@ -73,8 +75,12 @@ static void DrawProjectMenus(Project project)
 				bool showSimPausedBanner = project.simPaused;
 				if (showSimPausedBanner) SimPausedUI.DrawPausedBanner();
 				if (project.chipViewStack.Count > 1) ViewedChipsBar.DrawViewedChipsBanner(project, showSimPausedBanner);
+				if (Simulator.isCreatingACache) CreateCacheUI.DrawCreatingCacheInfo();
+				aMenuIsOpen = false;
 			}
 
+			if (aMenuIsOpen) Simulator.isCreatingACache = false; // Cancel current caching process when a menu gets opened
+
 			ContextMenu.Update();
 		}
 

Assets/Scripts/SaveSystem/DescriptionCreator.cs

@@ -37,6 +37,7 @@ public static ChipDescription CreateChipDescription(DevChipInstance chip)
 				NameLocation = hasSavedDesc ? descOld.NameLocation : NameDisplayLocation.Centre,
 				Size = size,
 				Colour = col,
+				ShouldBeCached = hasSavedDesc ? descOld.ShouldBeCached : false,
 
 				SubChips = subchips,
 				InputPins = inputPins,

Assets/Scripts/SaveSystem/Loader.cs

@@ -4,6 +4,7 @@
 using System.Linq;
 using DLS.Description;
 using DLS.Game;
+using DLS.Simulation;
 
 namespace DLS.SaveSystem
 {
@@ -24,6 +25,10 @@ public static Project LoadProject(string projectName)
 		{
 			ProjectDescription projectDescription = LoadProjectDescription(projectName);
 			ChipLibrary chipLibrary = LoadChipLibrary(projectDescription);
+
+			Simulator.combinationalChipCaches.Clear();
+			Simulator.chipsKnowToNotBeCombinational.Clear();
+
 			return new Project(projectDescription, chipLibrary);
 		}
 

Assets/Scripts/Simulation/SimChip.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using DLS.Description;
 
@@ -8,13 +9,15 @@ public class SimChip
 	{
 		public readonly ChipType ChipType;
 		public readonly int ID;
+		public readonly string Name;
 
 		// Some builtin chips, such as RAM, require an internal state for memory
 		// (can also be used for other arbitrary chip-specific data)
 		public readonly uint[] InternalState = Array.Empty<uint>();
 		public readonly bool IsBuiltin;
 		public SimPin[] InputPins = Array.Empty<SimPin>();
 		public int numConnectedInputs;
+		public bool shouldBeCached; // True, if the user specifically wanted this chip to be cached
 
 		public int numInputsReady;
 		public SimPin[] OutputPins = Array.Empty<SimPin>();
@@ -30,7 +33,9 @@ public SimChip(ChipDescription desc, int id, uint[] internalState, SimChip[] sub
 		{
 			SubChips = subChips;
 			ID = id;
+			Name = desc.Name;
 			ChipType = desc.ChipType;
+			shouldBeCached = desc.ShouldBeCached;
 			IsBuiltin = ChipType != ChipType.Custom;
 
 			// ---- Create pins (don't allocate unnecessarily as very many sim chips maybe created!) ----
@@ -85,6 +90,133 @@ public SimChip(ChipDescription desc, int id, uint[] internalState, SimChip[] sub
 			}
 		}
 
+		// Returns true, when this chip is purely combinational / stateless. This is the case, when the outputs of this chip depend entirely on the inputs and on nothing else.
+		public bool IsCombinational()
+		{
+			// Handle built in chips
+			switch (ChipType)
+			{
+				case ChipType.Nand:
+				case ChipType.TriStateBuffer:
+				case ChipType.Merge_1To4Bit:
+				case ChipType.Merge_1To8Bit:
+				case ChipType.Merge_4To8Bit:
+				case ChipType.Split_4To1Bit:
+				case ChipType.Split_8To4Bit:
+				case ChipType.Split_8To1Bit:
+					return true;
+				case ChipType.Clock:
+				case ChipType.Pulse:
+				case ChipType.dev_Ram_8Bit:
+				case ChipType.Rom_256x16:
+				case ChipType.SevenSegmentDisplay:
+				case ChipType.DisplayRGB:
+				case ChipType.DisplayDot:
+				case ChipType.DisplayLED:
+				case ChipType.Key:
+				case ChipType.Buzzer:
+					return false;
+			}
+
+			// Chip isn't combinational, if any of the subChips inputPins has more than one connection
+			foreach (SimChip subChip in SubChips)
+			{
+				foreach (SimPin inputPin in subChip.InputPins)
+				{
+					if (inputPin.numInputConnections > 1) return false;
+				}
+			}
+
+			// Can only be combinational if all subchips are combinational
+			foreach (SimChip subChip in SubChips)
+			{
+				// recursively make sure, that subchip is combinational
+				if (!subChip.IsCombinational()) return false;
+			}
+
+			// Check for loops in wiring using topo sort
+			Dictionary<int, List<int>> graph = new();     // chipID -> list of dependent chipIDs
+			Dictionary<int, int> inDegree = new();        // chipID -> number of incoming edges
+			// Build Graph
+			foreach (SimChip chip in SubChips)
+			{
+				int chipID = chip.ID;
+				if (!graph.ContainsKey(chipID)) graph[chipID] = new List<int>();
+				if (!inDegree.ContainsKey(chipID)) inDegree[chipID] = 0;
+
+				foreach (SimPin output in chip.OutputPins)
+				{
+					foreach (SimPin target in output.ConnectedTargetPins)
+					{
+						SimChip targetChip = target.parentChip;
+						if (targetChip == null || targetChip.ID == chipID) continue;
+
+						// Add edge: chip -> targetChip
+						if (!graph[chipID].Contains(targetChip.ID))
+						{
+							graph[chipID].Add(targetChip.ID);
+
+							// Update in-degree for topological sort
+							if (!inDegree.ContainsKey(targetChip.ID)) inDegree[targetChip.ID] = 0;
+
+							inDegree[targetChip.ID]++;
+						}
+					}
+				}
+			}
+			// Run topo sort
+			Queue<int> zeroInDegree = new();
+			foreach (var kvp in inDegree)
+			{
+				if (kvp.Value == 0) zeroInDegree.Enqueue(kvp.Key);
+			}
+			int visitedCount = 0;
+			while (zeroInDegree.Count > 0)
+			{
+				int chipID = zeroInDegree.Dequeue();
+				visitedCount++;
+
+				if (!graph.ContainsKey(chipID)) continue;
+
+				foreach (int neighborID in graph[chipID])
+				{
+					inDegree[neighborID]--;
+					if (inDegree[neighborID] == 0) zeroInDegree.Enqueue(neighborID);
+				}
+			}
+
+			// If we couldn't visit all chips, a cycle exists
+			if (visitedCount != inDegree.Count) return false;
+
+			return true;
+		}
+
+		public int CalculateNumberOfInputBits()
+		{
+			int numberOfBits = 0;
+			foreach (SimPin pin in InputPins)
+			{
+				numberOfBits += (int)pin.numberOfBits;
+			}
+			return numberOfBits;
+		}
+
+		public void ResetReceivedFlagsOnAllPins()
+		{
+			foreach(SimPin pin in InputPins)
+			{
+				pin.numInputsReceivedThisFrame = 0;
+			}
+			foreach (SimPin pin in OutputPins)
+			{
+				pin.numInputsReceivedThisFrame = 0;
+			}
+			foreach (SimChip subChip in SubChips)
+			{
+				subChip.ResetReceivedFlagsOnAllPins();
+			}
+		}
+
 		public void UpdateInternalState(uint[] source) => Array.Copy(source, InternalState, InternalState.Length);
 
 
@@ -218,7 +350,7 @@ public void AddPin(SimPin pin, bool isInput)
 			}
 		}
 
-		static SimPin CreateSimPinFromDescription(PinDescription desc, bool isInput, SimChip parent) => new(desc.ID, isInput, parent);
+		static SimPin CreateSimPinFromDescription(PinDescription desc, bool isInput, SimChip parent) => new(desc.ID, isInput, desc.BitCount, parent);
 
 		public void RemovePin(int removePinID)
 		{