/// <summary>
/// Processes primitive effects.
/// </summary>
/// <param name="relativeState">Relative state.</param>
/// <returns>Effect relevance (relevant, irrelevant, or anti-relevant).</returns>
private EffectRelevance ProcessPrimitiveEffects(IRelativeState relativeState)
{
bool anyRelevant = false;
foreach (var predicateAtom in relativeState.GetPredicates())
{
anyRelevant |= Effects.GroundedPositivePredicateEffects.Contains(predicateAtom);
if (Effects.GroundedNegativePredicateEffects.Contains(predicateAtom))
{
return(EffectRelevance.ANTI_RELEVANT);
}
}
foreach (var predicateAtom in relativeState.GetNegatedPredicates())
{
anyRelevant |= Effects.GroundedNegativePredicateEffects.Contains(predicateAtom);
if (Effects.GroundedPositivePredicateEffects.Contains(predicateAtom))
{
return(EffectRelevance.ANTI_RELEVANT);
}
}
foreach (var function in relativeState.GetObjectFunctions())
{
ITerm assignValue;
if (Effects.GroundedObjectFunctionAssignmentEffects.TryGetValue(function.Key, out assignValue))
{
ConstantTerm constantValue = assignValue as ConstantTerm;
if (constantValue == null || constantValue.NameId != function.Value)
{
// surely assigning different value -> anti-relevant
return(EffectRelevance.ANTI_RELEVANT);
}
anyRelevant = true;
}
}
foreach (var function in relativeState.GetNumericFunctions())
{
INumericExpression assignExpression;
if (Effects.GroundedNumericFunctionAssignmentEffects.TryGetValue(function.Key, out assignExpression))
{
Number numberValue = assignExpression as Number;
if (numberValue == null || !numberValue.Value.Equals(function.Value))
{
// surely assigning different value -> anti-relevant
return(EffectRelevance.ANTI_RELEVANT);
}
anyRelevant = true;
}
}
return((anyRelevant) ? EffectRelevance.RELEVANT : EffectRelevance.IRRELEVANT);
}
/// <summary>
/// Generates all possible PDDL states meeting conditions specified by the relative state. Lazy generated via yield return.
/// </summary>
/// <param name="relativeState">Reference relative state.</param>
/// <param name="problem">Planning problem.</param>
/// <returns>All possible PDDL states meeting the conditions.</returns>
public static IEnumerable <IState> EnumerateStates(IRelativeState relativeState, Problem problem)
{
// note: numeric function assignments are not enumerated (as it is generally infinite), but only fixed by the values of the source state
Func <IAtom, bool?> predicateChecker = (predicate) =>
{
if (relativeState.HasPredicate(predicate))
{
return(true);
}
else if (relativeState.HasNegatedPredicate(predicate))
{
return(false);
}
return(null);
};
Func <IAtom, int> objectFunctionChecker = relativeState.GetObjectFunctionValue;
IState initState = new State(problem.IdManager);
foreach (var numericFunction in relativeState.GetNumericFunctions())
{
initState.AssignNumericFunction(numericFunction.Key, numericFunction.Value);
}
var predicates = problem.EvaluationManager.GroundingManager.GetAllGroundedPredicates();
var objectFunctions = problem.EvaluationManager.GroundingManager.GetAllGroundedObjectFunctions();
foreach (var state in EnumerateStatesByPredicates(0, predicates, initState, predicateChecker))
{
foreach (var resultState in EnumerateStatesByObjectFunctions(0, objectFunctions, state, objectFunctionChecker))
{
yield return(resultState);
}
}
}