Merge pull request #29 from giollord/main

Fixed delta cost calculation in ActionAStar.Heuristic

Examples/Properties/launchSettings.json

@@ -19,6 +19,10 @@
     "comparative happiness": {
       "commandName": "Project",
       "commandLineArgs": "comparativeHappiness"
+    },
+    "car": {
+      "commandName": "Project",
+      "commandLineArgs": "car"
     }
   }
 }

MountainGoap/Action.cs

@@ -91,7 +91,8 @@ public class Action {
         /// <param name="parameterPostconditions">Parameter postconditions copied to state after the action is successfully executed.</param>
         /// <param name="stateMutator">Callback for modifying state after action execution or evaluation.</param>
         /// <param name="stateChecker">Callback for checking state before action execution or evaluation.</param>
-        public Action(string? name = null, Dictionary<string, PermutationSelectorCallback>? permutationSelectors = null, ExecutorCallback? executor = null, float cost = 1f, CostCallback? costCallback = null, Dictionary<string, object?>? preconditions = null, Dictionary<string, ComparisonValuePair>? comparativePreconditions = null, Dictionary<string, object?>? postconditions = null, Dictionary<string, object>? arithmeticPostconditions = null, Dictionary<string, string>? parameterPostconditions = null, StateMutatorCallback? stateMutator = null, StateCheckerCallback? stateChecker = null) {
+        /// <param name="stateCostDeltaMultiplier">Callback for multiplier for delta value to provide delta cost.</param>
+        public Action(string? name = null, Dictionary<string, PermutationSelectorCallback>? permutationSelectors = null, ExecutorCallback? executor = null, float cost = 1f, CostCallback? costCallback = null, Dictionary<string, object?>? preconditions = null, Dictionary<string, ComparisonValuePair>? comparativePreconditions = null, Dictionary<string, object?>? postconditions = null, Dictionary<string, object>? arithmeticPostconditions = null, Dictionary<string, string>? parameterPostconditions = null, StateMutatorCallback? stateMutator = null, StateCheckerCallback? stateChecker = null, StateCostDeltaMultiplierCallback? stateCostDeltaMultiplier = null) {
             if (permutationSelectors == null) this.permutationSelectors = new();
             else this.permutationSelectors = permutationSelectors;
             if (executor == null) this.executor = DefaultExecutorCallback;
@@ -106,8 +107,16 @@ public Action(string? name = null, Dictionary<string, PermutationSelectorCallbac
             if (parameterPostconditions != null) this.parameterPostconditions = parameterPostconditions;
             if (stateMutator != null) this.stateMutator = stateMutator;
             if (stateChecker != null) this.stateChecker = stateChecker;
+            StateCostDeltaMultiplier = stateCostDeltaMultiplier ?? DefaultStateCostDeltaMultiplier;
         }
 
+        /// <summary>
+        /// Gets or sets multiplier for delta value to provide delta cost.
+        /// </summary>
+        public StateCostDeltaMultiplierCallback? StateCostDeltaMultiplier { get; set; }
+
+        public static float DefaultStateCostDeltaMultiplier(Action? action, string stateKey) => 1f;
+
         /// <summary>
         /// Event that triggers when an action begins executing.
         /// </summary>
@@ -128,7 +137,7 @@ public Action(string? name = null, Dictionary<string, PermutationSelectorCallbac
         /// </summary>
         /// <returns>A copy of the action.</returns>
         public Action Copy() {
-            var newAction = new Action(Name, permutationSelectors, executor, cost, costCallback, preconditions.Copy(), comparativePreconditions.Copy(), postconditions.Copy(), arithmeticPostconditions.CopyNonNullable(), parameterPostconditions.Copy(), stateMutator, stateChecker) {
+            var newAction = new Action(Name, permutationSelectors, executor, cost, costCallback, preconditions.Copy(), comparativePreconditions.Copy(), postconditions.Copy(), arithmeticPostconditions.CopyNonNullable(), parameterPostconditions.Copy(), stateMutator, stateChecker, StateCostDeltaMultiplier) {
                 parameters = parameters.Copy()
             };
             return newAction;

MountainGoap/CallbackDelegates/StateCostDeltaMultiplierCallback.cs

@@ -0,0 +1,13 @@
+// <copyright file="StateMutatorCallback.cs" company="Chris Muller">
+// Copyright (c) Chris Muller. All rights reserved.
+// </copyright>
+
+namespace MountainGoap {
+    /// <summary>
+    /// Delegate type for a callback that provides multiplier for delta value of the respective key to obtain delta cost to use with ExtremeGoal and ComparativeGoal.
+    /// </summary>
+    /// <param name="action">Action being executed or evaluated.</param>
+    /// <param name="stateKey">Key to provide multiplier for</param>
+    /// <returns>Multiplier for the delta value to get delta cost</returns>
+    public delegate float StateCostDeltaMultiplierCallback(Action? action, string stateKey);
+}

MountainGoap/Internals/ActionAStar.cs

@@ -76,29 +76,31 @@ private static float Heuristic(ActionNode actionNode, BaseGoal goal, ActionNode
             else if (goal is ExtremeGoal extremeGoal) {
                 foreach (var kvp in extremeGoal.DesiredState) {
                     var valueDiff = 0f;
+                    var valueDiffMultiplier = (actionNode?.Action?.StateCostDeltaMultiplier ?? Action.DefaultStateCostDeltaMultiplier).Invoke(actionNode?.Action, kvp.Key);
                     if (actionNode.State.ContainsKey(kvp.Key) && actionNode.State[kvp.Key] == null) {
                         cost += float.PositiveInfinity;
                         continue;
                     }
                     if (actionNode.State.ContainsKey(kvp.Key) && extremeGoal.DesiredState.ContainsKey(kvp.Key)) valueDiff = Convert.ToSingle(actionNode.State[kvp.Key]) - Convert.ToSingle(current.State[kvp.Key]);
                     if (!actionNode.State.ContainsKey(kvp.Key)) cost += float.PositiveInfinity;
                     else if (!current.State.ContainsKey(kvp.Key)) cost += float.PositiveInfinity;
-                    else if (kvp.Value && actionNode.State[kvp.Key] is object a && current.State[kvp.Key] is object b && IsLowerThanOrEquals(a, b)) cost += 1f / valueDiff;
-                    else if (!kvp.Value && actionNode.State[kvp.Key] is object a2 && current.State[kvp.Key] is object b2 && IsHigherThanOrEquals(a2, b2)) cost += 1f / (1 - valueDiff);
+                    else if (!kvp.Value && actionNode.State[kvp.Key] is object a && current.State[kvp.Key] is object b && IsLowerThanOrEquals(a, b)) cost += valueDiff * valueDiffMultiplier;
+                    else if (kvp.Value && actionNode.State[kvp.Key] is object a2 && current.State[kvp.Key] is object b2 && IsHigherThanOrEquals(a2, b2)) cost -= valueDiff * valueDiffMultiplier;
                 }
             }
             else if (goal is ComparativeGoal comparativeGoal) {
                 foreach (var kvp in comparativeGoal.DesiredState) {
                     var valueDiff2 = 0f;
-                    if (actionNode.State.ContainsKey(kvp.Key) && comparativeGoal.DesiredState.ContainsKey(kvp.Key)) valueDiff2 = Math.Abs(Convert.ToSingle(kvp.Value.Value) - Convert.ToSingle(actionNode.State[kvp.Key]));
+                    var valueDiffMultiplier = (actionNode?.Action?.StateCostDeltaMultiplier ?? Action.DefaultStateCostDeltaMultiplier).Invoke(actionNode?.Action, kvp.Key);
+                    if (actionNode.State.ContainsKey(kvp.Key) && comparativeGoal.DesiredState.ContainsKey(kvp.Key)) valueDiff2 = Math.Abs(Convert.ToSingle(actionNode.State[kvp.Key]) - Convert.ToSingle(current.State[kvp.Key]));
                     if (!actionNode.State.ContainsKey(kvp.Key)) cost += float.PositiveInfinity;
                     else if (!current.State.ContainsKey(kvp.Key)) cost += float.PositiveInfinity;
                     else if (kvp.Value.Operator == ComparisonOperator.Undefined) cost += float.PositiveInfinity;
-                    else if (kvp.Value.Operator == ComparisonOperator.Equals && actionNode.State[kvp.Key] is object obj && !obj.Equals(comparativeGoal.DesiredState[kvp.Key].Value)) cost += valueDiff2;
-                    else if (kvp.Value.Operator == ComparisonOperator.LessThan && actionNode.State[kvp.Key] is object a && comparativeGoal.DesiredState[kvp.Key].Value is object b && !IsLowerThan(a, b)) cost += valueDiff2;
-                    else if (kvp.Value.Operator == ComparisonOperator.GreaterThan && actionNode.State[kvp.Key] is object a2 && comparativeGoal.DesiredState[kvp.Key].Value is object b2 && !IsHigherThan(a2, b2)) cost += valueDiff2;
-                    else if (kvp.Value.Operator == ComparisonOperator.LessThanOrEquals && actionNode.State[kvp.Key] is object a3 && comparativeGoal.DesiredState[kvp.Key].Value is object b3 && !IsLowerThanOrEquals(a3, b3)) cost += valueDiff2;
-                    else if (kvp.Value.Operator == ComparisonOperator.GreaterThanOrEquals && actionNode.State[kvp.Key] is object a4 && comparativeGoal.DesiredState[kvp.Key].Value is object b4 && !IsHigherThanOrEquals(a4, b4)) cost += valueDiff2;
+                    else if (kvp.Value.Operator == ComparisonOperator.Equals && actionNode.State[kvp.Key] is object obj && !obj.Equals(comparativeGoal.DesiredState[kvp.Key].Value)) cost += valueDiff2 * valueDiffMultiplier;
+                    else if (kvp.Value.Operator == ComparisonOperator.LessThan && actionNode.State[kvp.Key] is object a && comparativeGoal.DesiredState[kvp.Key].Value is object b && !IsLowerThan(a, b)) cost += valueDiff2 * valueDiffMultiplier;
+                    else if (kvp.Value.Operator == ComparisonOperator.GreaterThan && actionNode.State[kvp.Key] is object a2 && comparativeGoal.DesiredState[kvp.Key].Value is object b2 && !IsHigherThan(a2, b2)) cost += valueDiff2 * valueDiffMultiplier;
+                    else if (kvp.Value.Operator == ComparisonOperator.LessThanOrEquals && actionNode.State[kvp.Key] is object a3 && comparativeGoal.DesiredState[kvp.Key].Value is object b3 && !IsLowerThanOrEquals(a3, b3)) cost += valueDiff2 * valueDiffMultiplier;
+                    else if (kvp.Value.Operator == ComparisonOperator.GreaterThanOrEquals && actionNode.State[kvp.Key] is object a4 && comparativeGoal.DesiredState[kvp.Key].Value is object b4 && !IsHigherThanOrEquals(a4, b4)) cost += valueDiff2 * valueDiffMultiplier;
                 }
             }
             return cost;