/// <summary>
/// Mutates a random connection by inverting its current Enabled status.
/// </summary>
public void Mutate_LinkToggle()
{
if (ConnectionGenes.Count == 0) //There are no connections, nothing to toggle.
{
return;
}
ConnectionGene connectionGene = ConnectionGenes.RandomValue(Random).Take(1).ElementAt(0);
if (connectionGene != null)
{
connectionGene.Enabled = !connectionGene.Enabled;
}
}
/// <summary>
/// Mutates a random connection by shifting its weight up or down by a radom value. Creates connection if there is none.
/// </summary>
public void Mutate_WeightShift()
{
if (ConnectionGenes.Count == 0)
{
Mutate_Link();
}
else
{
ConnectionGene connectionGene = ConnectionGenes.RandomValue(Random).Take(1).ElementAt(0);
if (connectionGene != null)
{
connectionGene.Weight = connectionGene.Weight + Pedigree.Mutation_WeightShift * (Random.NextDouble() * 2 - 1);
}
}
}
/// <summary>
/// Mutates a random connection splitting it with a node.
/// </summary>
public void Mutate_Node()
{
if (NodeGenes.Count >= Pedigree.MaxNodes)
{
return; //Do nothing if we have max nodes.
}
else if (ConnectionGenes.Count == 0)
{
return; //Literally cannot make a node.
}
ConnectionGene connectionGene = ConnectionGenes.RandomValue(Random).Take(1).ElementAt(0);
if (connectionGene == null)
{
return;
}
NodeGene from = NodeGenes[connectionGene.ConnectionGenePattern.From.InnovationNumber];
NodeGene to = NodeGenes[connectionGene.ConnectionGenePattern.To.InnovationNumber];
NodeGene created = Pedigree.Create_NodeGene(connectionGene);
if (NodeGenes.ContainsKey(created.NodeGenePattern.InnovationNumber))
{
return; //TODO maybe retry here as well?
}
NodeGenes.Add(created.NodeGenePattern.InnovationNumber, created);
ConnectionGene created_connectionGene_1 = Pedigree.Create_ConnectionGene(from, created, 1, true); //Default weight of 1.
ConnectionGene created_connectionGene_2 = Pedigree.Create_ConnectionGene(created, to, connectionGene.Weight, connectionGene.Enabled);
ConnectionGenes.Remove(connectionGene.ConnectionGenePattern.InnovationNumber);
ConnectionGenes.Add(created_connectionGene_1.ConnectionGenePattern.InnovationNumber, created_connectionGene_1);
ConnectionGenes.Add(created_connectionGene_2.ConnectionGenePattern.InnovationNumber, created_connectionGene_2);
}