private AIOption ChooseOption(AbstractAIBrain abstractAiBrain)
{
// Calcul maxWeight and return null if equal to zero
int maxWeight = Options[abstractAiBrain].Max(option => option.Weight);
if (maxWeight == 0)
{
return(null);
}
// Returning best option for no random
if (AlwaysPickBestChoice)
{
return(Options[abstractAiBrain].FirstOrDefault());
}
// Rolling probability on weighted random
_lastProbabilityResult = Random.Range(0f, 1f);
float probabilitySum = 0f;
foreach (AIOption dualUtility in Options[abstractAiBrain].FindAll(option => option.Weight == maxWeight))
{
probabilitySum += dualUtility.Probability;
if (probabilitySum >= _lastProbabilityResult)
{
return(dualUtility);
}
}
return(null);
}
private void CalculateOptions(AbstractAIBrain utilityAiBrain)
{
if (utilityAiBrain == null)
{
return;
}
// Setup Contexts
utilityAiBrain.GetNodes <EntryNode>().ForEach(node => node.SetContext(this));
utilityAiBrain.GetNodes <ActionNode>().ForEach(node => node.SetContext(this));
// Add the brain to the option dictionary
if (Options.ContainsKey(utilityAiBrain))
{
Options[utilityAiBrain].Clear();
}
else
{
Options.Add(utilityAiBrain, new List <AIOption>());
}
utilityAiBrain.GetNodes <OptionNode>().ForEach(node => Options[utilityAiBrain]
.AddRange(node.GetOptions()));
// Return if no option found
if (Options[utilityAiBrain].Count == 0)
{
return;
}
// Calculate Probability
foreach (AIOption aiOption in Options[utilityAiBrain])
{
aiOption.Probability = aiOption.Utility / Options[utilityAiBrain]
.Where(option => option.Weight == aiOption.Weight)
.Sum(option => option.Utility);
}
// Order by Weight then Utility
Options[utilityAiBrain] = Options[utilityAiBrain].OrderByDescending(option => option.Weight).ThenByDescending(option => option.Utility).ToList();
}
