Improve efficiency of command list execution #96

Changed the Block and Command classes to use a simple execution loop
inside a coroutine.
The Call command now has a ‘Stop Parent Block’ parameter for when you
want to continue executing the current block after a Call command.

Assets/Fungus/Flowchart/Editor/CallEditor.cs

@@ -9,10 +9,12 @@ namespace Fungus
 	public class CallEditor : CommandEditor 
 	{
 		protected SerializedProperty targetBlockProp;
+		protected SerializedProperty stopParentBlockProp;
 
 		protected virtual void OnEnable()
 		{
 			targetBlockProp = serializedObject.FindProperty("targetBlock");
+			stopParentBlockProp = serializedObject.FindProperty("stopParentBlock");
 		}
 
 		public override void DrawCommandGUI()
@@ -32,6 +34,8 @@ namespace Fungus
 										 new GUIContent("<Continue>"), 
 										 flowchart);
 
+			EditorGUILayout.PropertyField(stopParentBlockProp);
+
 			serializedObject.ApplyModifiedProperties();
 		}
 	}

Assets/Fungus/Flowchart/Editor/CommandListAdaptor.cs

@@ -362,7 +362,7 @@ namespace Fungus
 				GUI.Label(commandLabelRect, commandName, commandLabelStyle);
 			}
 			
-			if (command.IsExecuting())
+			if (command.isExecuting)
 			{
 				Rect iconRect = new Rect(commandLabelRect);
 				iconRect.x += iconRect.width - commandLabelRect.width - 20;

Assets/Fungus/Flowchart/Editor/FlowchartWindow.cs

@@ -581,7 +581,7 @@ namespace Fungus
 					}
 				}
 
-				bool highlight = command.IsExecuting() || (blockIsSelected && commandIsSelected);
+				bool highlight = command.isExecuting || (blockIsSelected && commandIsSelected);
 
 				if (highlightedOnly && !highlight ||
 				    !highlightedOnly && highlight)

Assets/Fungus/Flowchart/Scripts/Block.cs

@@ -21,6 +21,15 @@ namespace Fungus
 	[AddComponentMenu("")]
 	public class Block : Node 
 	{
+		public enum ExecutionState
+		{
+			Idle,
+			Executing,
+		}
+
+		[NonSerialized]
+		public ExecutionState executionState;
+
 		[HideInInspector]
 		public int itemId = -1; // Invalid flowchart item id
 
@@ -55,6 +64,12 @@ namespace Fungus
 
 		protected int executionCount;
 
+		/**
+		 * Controls the next command to execute in the block execution coroutine.
+		 */
+		[NonSerialized]
+		public int jumpToCommandIndex = -1;
+
 		protected virtual void Awake()
 		{
 			// Give each child command a reference back to its parent block
@@ -117,13 +132,7 @@ namespace Fungus
 
 		public virtual bool IsExecuting()
 		{
-			Flowchart flowchart = GetFlowchart();
-			if (flowchart == null)
-			{
-				return false;
-			}
-
-			return (activeCommand != null);
+			return (executionState == ExecutionState.Executing);
 		}
 
 		public virtual int GetExecutionCount()
@@ -131,100 +140,101 @@ namespace Fungus
 			return executionCount;
 		}
 
-		public virtual void ExecuteCommand(int commandIndex)
+		public virtual bool Execute()
 		{
-			if (activeCommand == null)
-			{
-				previousActiveCommandIndex = -1;
-			}
-			else
+			if (executionState != ExecutionState.Idle)
 			{
-				previousActiveCommandIndex = activeCommand.commandIndex;
+				return false;
 			}
 
-			if (commandIndex >= commandList.Count)
-			{
-				Stop();
-				return;
-			}
+			executionCount++;
+			StartCoroutine(ExecuteBlock());
 
-			if (commandIndex == 0)
-			{
-				executionCount++;
-			}
+			return true;
+		}
 
+		protected virtual IEnumerator ExecuteBlock()
+		{
 			Flowchart flowchart = GetFlowchart();
+			executionState = ExecutionState.Executing;
 
-			// Skip disabled commands, comments and labels
-			while (commandIndex < commandList.Count &&
-				   (!commandList[commandIndex].enabled || 
-			 		commandList[commandIndex].GetType() == typeof(Comment) ||
-			 	    commandList[commandIndex].GetType() == typeof(Label)))
+			int i = 0;
+			while (true)
 			{
-				commandIndex = commandList[commandIndex].commandIndex + 1;
-			}
+				// Executing commands specify the next command to skip to by setting jumpToCommandIndex using Command.Continue()
+				if (jumpToCommandIndex > -1)
+				{
+					i = jumpToCommandIndex;
+					jumpToCommandIndex = -1;
+				}
 
-			if (commandIndex >= commandList.Count)
-			{
-				Stop();
-				return;
-			}
+				// Skip disabled commands, comments and labels
+				while (i < commandList.Count &&
+				       (!commandList[i].enabled || 
+				 		commandList[i].GetType() == typeof(Comment) ||
+				 		commandList[i].GetType() == typeof(Label)))
+				{
+					i = commandList[i].commandIndex + 1;
+				}
 
-			Command nextCommand = commandList[commandIndex];
+				if (i >= commandList.Count)
+				{
+					break;
+				}
 
-			activeCommand = null;
-			executingIconTimer = 0.5f;
+				// The previous active command is needed for if / else / else if commands
+				if (activeCommand == null)
+				{
+					previousActiveCommandIndex = -1;
+				}
+				else
+				{
+					previousActiveCommandIndex = activeCommand.commandIndex;
+				}
+
+				Command command = commandList[i];
+				activeCommand = command;
+				executingIconTimer = 0.5f;
 
-			if (nextCommand == null)
-			{
-				Stop();
-			}
-			else
-			{
 				if (flowchart.gameObject.activeInHierarchy)
 				{
 					// Auto select a command in some situations
-					if ((flowchart.selectedCommands.Count == 0 && commandIndex == 0) ||
+					if ((flowchart.selectedCommands.Count == 0 && i == 0) ||
 					    (flowchart.selectedCommands.Count == 1 && flowchart.selectedCommands[0].commandIndex == previousActiveCommandIndex))
 					{
 						flowchart.ClearSelectedCommands();
-						flowchart.AddSelectedCommand(nextCommand);
-					}
-
-					if (runSlowInEditor &&
-					    nextCommand.RunSlowInEditor())
-					{
-						StartCoroutine(ExecuteAfterDelay(nextCommand, flowchart.runSlowDuration));
-					}
-					else
-					{
-						activeCommand = nextCommand;
-						nextCommand.Execute();
+						flowchart.AddSelectedCommand(commandList[i]);
 					}
 				}
-			}
 
-		}
+				command.isExecuting = true;
+				command.Execute();
 
-		IEnumerator ExecuteAfterDelay(Command nextCommand, float delay)
-		{
-			activeCommand = nextCommand;
-			yield return new WaitForSeconds(delay);
-			nextCommand.Execute();
-		}
+				// Wait until the executing command sets another command to jump to via Command.Continue()
+				while (jumpToCommandIndex == -1)
+				{
+					yield return null;
+				}
 
-		public virtual void Stop()
-		{
-			Flowchart flowchart = GetFlowchart();
-			if (flowchart == null)
-			{
-				return;
+				if (runSlowInEditor)
+				{
+					yield return new WaitForSeconds(flowchart.runSlowDuration);
+				}
+
+				command.isExecuting = false;
 			}
 
+			executionState = ExecutionState.Idle;
 			activeCommand = null;
 			flowchart.ClearSelectedCommands();
 		}
 
+		public virtual void Stop()
+		{
+			// This will cause the execution loop to break on the next iteration
+			jumpToCommandIndex = int.MaxValue;
+		}
+
 		public virtual List<Block> GetConnectedBlocks()
 		{
 			List<Block> connectedBlocks = new List<Block>();

Assets/Fungus/Flowchart/Scripts/Command.cs

@@ -45,6 +45,12 @@ namespace Fungus
 		[NonSerialized]
 		public int commandIndex;
 
+		/**
+		 * Set to true by the parent block while the command is executing.
+		 */
+		[NonSerialized]
+		public bool isExecuting;
+
 		/**
 		 * Reference to the Block object that this command belongs to.
 		 * This reference is only populated at runtime and in the editor when the 
@@ -64,16 +70,6 @@ namespace Fungus
 			return flowchart;
 		}
 
-		public virtual bool IsExecuting()
-		{
-			if (parentBlock == null)
-			{
-				return false;
-			}
-
-			return (parentBlock.activeCommand == this);
-		}
-
 		public virtual void Execute()
 		{
 			OnEnter();
@@ -89,7 +85,7 @@ namespace Fungus
 			OnExit();
 			if (parentBlock != null)
 			{
-				parentBlock.ExecuteCommand(nextCommandIndex);
+				parentBlock.jumpToCommandIndex = nextCommandIndex;
 			}
 		}
 
@@ -102,28 +98,30 @@ namespace Fungus
 			}
 		}
 
-		public virtual void ExecuteBlock(Block s)
+		public virtual void ExecuteBlock(Block s, bool stopParentBlock)
 		{
 			OnExit();
 			if (parentBlock != null)
 			{
 				Flowchart flowchart = parentBlock.GetFlowchart();
+				if (flowchart == null)
+				{
+					return;
+				}
 
-				// Record the currently selected block because Stop() will clear it.
-				Block selectedBlock = flowchart.selectedBlock;
-
-				parentBlock.Stop();
-				if (flowchart != null)
+				if (stopParentBlock)
 				{
+					parentBlock.Stop();
+
 					// If the executing block is currently selected then follow the execution 
 					// onto the next block in the inspector.
-					if (selectedBlock == parentBlock)
+					if (flowchart.selectedBlock == parentBlock)
 					{
 						flowchart.selectedBlock = s;
 					}
-
-					flowchart.ExecuteBlock(s);
 				}
+
+				flowchart.ExecuteBlock(s);
 			}
 		}
 

Assets/Fungus/Flowchart/Scripts/Commands/Call.cs

@@ -13,14 +13,21 @@ namespace Fungus
 	public class Call : Command
 	{	
 		[FormerlySerializedAs("targetSequence")]
-		[Tooltip("Block to execute")]
+		[Tooltip("Block to start executing")]
 		public Block targetBlock;
 	
+		[Tooltip("Stop executing the parent block that contains this command")]
+		public bool stopParentBlock = true;
+
 		public override void OnEnter()
 		{
 			if (targetBlock != null)
 			{
-				ExecuteBlock(targetBlock);
+				ExecuteBlock(targetBlock, stopParentBlock);
+				if (!stopParentBlock)
+				{
+					Continue();
+				}
 			}
 			else
 			{		

Assets/Fungus/Flowchart/Scripts/Flowchart.cs

@@ -242,7 +242,7 @@ namespace Fungus
 			}
 
 			// Execute the first command in the command list
-			block.ExecuteCommand(0);
+			block.Execute();
 
 			return true;
 		}

Assets/Fungus/Narrative/Deprecated/Choose.cs

@@ -100,7 +100,7 @@ namespace Fungus
 						}
 						else
 						{
-							ExecuteBlock(onSelectBlock);
+							ExecuteBlock(onSelectBlock, true);
 						}
 					};
 					
@@ -131,7 +131,7 @@ namespace Fungus
 		public override void GetConnectedBlocks (ref List<Block> connectedBlocks)
 		{
 			// Show connected blocks from preceding AddOption commands
-			if (IsExecuting())
+			if (isExecuting)
 			{
 				foreach (Option option in options)
 				{
@@ -175,7 +175,7 @@ namespace Fungus
 				{
 					options.Clear();
 					showBasicGUI = false;
-					ExecuteBlock(option.targetBlock);
+					ExecuteBlock(option.targetBlock, true);
 				}
 			}
 			

Assets/Fungus/Narrative/Scripts/MenuDialog.cs

@@ -126,7 +126,7 @@ namespace Fungus
 
 							gameObject.SetActive(false);
 
-							block.ExecuteCommand(0);
+							block.Execute();
 						}
 					});
 
@@ -199,7 +199,7 @@ namespace Fungus
 
 			if (targetBlock != null)
 			{
-				targetBlock.ExecuteCommand(0);
+				targetBlock.Execute();
 			}
 		}
 	}