/// <summary>
/// Creates a brain based on the genes of 2 parent brains.
/// For each gene in parent1 we check if parent2 has a gene with the same innovation number, if this is the case we randomly choose a parent to get the gene from.
/// If a gene only exists in one parent we add it no matter what.
/// </summary>
/// <param name="parent2Brain">The other parent.</param>
/// <returns>Returns a child brain based on the genes of this brain and the passed brain.</returns>
public Brain Crossover(Brain parent2Brain)
{
_childGenes.Clear();
List <ConnectionGene> parent2 = new List <ConnectionGene>(parent2Brain.ConnectionGenes);
foreach (ConnectionGene gene in ConnectionGenes)
{
ConnectionGene geneToRemove = default;
ConnectionGene geneToAdd = gene;
ConnectionGene gene2 = parent2Brain.ConnectionGenes.SingleOrDefault(gen => gen.InnovationNumber == gene.InnovationNumber);
if (gene2 != default)
{
geneToRemove = gene2;
geneToAdd = TrainingRoom.Random.NextDouble() < 0.5 ? gene : gene2;
}
geneToAdd = geneToAdd.Clone();
if (geneToRemove != default)
{
parent2.Remove(geneToRemove);
}
if (!geneToAdd.Enabled && TrainingRoom.Random.NextDouble() < TrainingRoom.TrainingRoomSettings.EnableConnectionChance)
{
geneToAdd.Enabled = true;
}
_childGenes.Add(geneToAdd);
}
_childGenes.AddRange(parent2);
return(new Brain(Guid.NewGuid(), TrainingRoom, _childGenes));
}
/// <summary>
/// Creates an organism based on the genes of 2 parent organisms.
/// For each gene in parent1 we check if parent2 has a gene with the same innovation number, if this is the case we randomly choose a parent to get the gene from.
/// If a gene only exists in one parent we add it no matter what.
/// </summary>
/// <param name="parent2Organism">The other parent.</param>
/// <param name="trainingRoomSettings">The training room settings.</param>
/// <returns>Returns a child organism based on the genes of this organism and the passed organism.</returns>
public Organism Crossover(Organism parent2Organism, TrainingRoomSettings trainingRoomSettings)
{
// Clears the temporary child genes list for re-use.
_childGenes.Clear();
// Copies the organisms from parent2.
List <ConnectionGene> parent2 = new List <ConnectionGene>(parent2Organism.ConnectionGenes);
// Pre-generates a child id for creating connection genes.
Guid childId = Guid.NewGuid();
foreach (ConnectionGene gene in ConnectionGenes)
{
// Prepares a gene to remove and add.
ConnectionGene geneToRemove = default;
ConnectionGene geneToAdd = gene;
// Tries to find a connection gene based on the current connection gene in the parent, and if not found, gives a default.
ConnectionGene gene2 = parent2Organism.ConnectionGenes.SingleOrDefault(gen => gen.InnovationNumber == gene.InnovationNumber);
// If the gene is not a default connection gene.
if (gene2 != default)
{
// Set it for removal.
geneToRemove = gene2;
// Depending on a random set the current gene or a random gene to add.
geneToAdd = trainingRoomSettings.Random.NextDouble() < 0.5 ? gene : gene2;
}
// Clone the gene to add with the new id.
geneToAdd = geneToAdd.Clone(childId);
// If the gene to remove is not default, remove it from its parent.
if (geneToRemove != default)
{
parent2.Remove(geneToRemove);
}
// If the gene to add is not enabled and a random is lower than the enable connection chance, enable the gene.
if (!geneToAdd.Enabled && trainingRoomSettings.Random.NextDouble() < trainingRoomSettings.EnableConnectionChance)
{
geneToAdd.Enabled = true;
}
// Add gene to the temporary child genes list.
_childGenes.Add(geneToAdd);
}
// Add all remaining genes in the parent to the child genes.
_childGenes.AddRange(parent2);
// Return a new organism with all new genes.
return(new Organism(childId, trainingRoomSettings, Generation + 1, _childGenes));
}