/// <summary>
/// Add a ConnectionGene to the builder, but only if the connection is not already present (as determined by it's neuron ID endpoints).
/// </summary>
/// <param name="connectionGene">The connection to add.</param>
/// <param name="parentGenome">The connection's parent genome. This is used to obtain NeuronGene(s) for the connection endpoints.</param>
/// <param name="overwriteExisting">A flag that indicates if this connection should take precedence over an existing connection with
/// the same endpoints.</param>
public void TryAddGene(ConnectionGene connectionGene, NeatGenome parentGenome, bool overwriteExisting)
{
// Check if a matching gene has already been added.
ConnectionEndpointsStruct connectionKey = new ConnectionEndpointsStruct(connectionGene.SourceNodeId, connectionGene.TargetNodeId);
ConnectionGene existingConnectionGene;
if (!_connectionGeneDictionary.TryGetValue(connectionKey, out existingConnectionGene))
{ // Add new connection gene.
ConnectionGene connectionGeneCopy = new ConnectionGene(connectionGene);
_connectionGeneDictionary.Add(connectionKey, connectionGeneCopy);
// Insert connection gene into a list. Use more efficient approach (append to end) if we know the gene belongs at the end.
if (connectionGeneCopy.InnovationId > _highestConnectionGeneId)
{
_connectionGeneList.Add(connectionGeneCopy);
_highestConnectionGeneId = connectionGeneCopy.InnovationId;
}
else
{
_connectionGeneList.InsertIntoPosition(connectionGeneCopy);
}
// Add neuron genes (if not already added).
// Source neuron.
NeuronGene srcNeuronGene;
if (!_neuronDictionary.TryGetValue(connectionGene.SourceNodeId, out srcNeuronGene))
{
srcNeuronGene = parentGenome.NeuronGeneList.GetNeuronById(connectionGene.SourceNodeId);
srcNeuronGene = new NeuronGene(srcNeuronGene, false); // Make a copy.
_neuronDictionary.Add(srcNeuronGene.Id, srcNeuronGene);
}
// Target neuron.
NeuronGene tgtNeuronGene;
if (!_neuronDictionary.TryGetValue(connectionGene.TargetNodeId, out tgtNeuronGene))
{
tgtNeuronGene = parentGenome.NeuronGeneList.GetNeuronById(connectionGene.TargetNodeId);
tgtNeuronGene = new NeuronGene(tgtNeuronGene, false); // Make a copy.
_neuronDictionary.Add(tgtNeuronGene.Id, tgtNeuronGene);
}
// Register connectivity with each neuron.
srcNeuronGene.TargetNeurons.Add(tgtNeuronGene.Id);
tgtNeuronGene.SourceNeurons.Add(srcNeuronGene.Id);
}
else if (overwriteExisting)
{ // The genome we are building already has a connection with the same neuron endpoints as the one we are
// trying to add. It didn't match up during correlation because it has a different innovation number, this
// is possible because the innovation history buffers throw away old innovations in a FIFO manner in order
// to prevent them from bloating.
// Here the 'overwriteExisting' flag is set so the gene we are currently trying to add is probably from the
// fitter parent, and therefore we want to use its connection weight in place of the existing gene's weight.
existingConnectionGene.Weight = connectionGene.Weight;
}
}
public void ConectionBufferTest()
{
NeatGenomeFactory genomeFactory = new NeatGenomeFactory(3, 1);
for (uint i = 0; i < 200000; i++)
{
ConnectionEndpointsStruct endpointsStruct = new ConnectionEndpointsStruct(i, i+1);
AddedNeuronGeneStruct addedNeuronGeneStruct = new AddedNeuronGeneStruct(genomeFactory.InnovationIdGenerator);
genomeFactory.AddedConnectionBuffer.Enqueue(endpointsStruct, i);
genomeFactory.AddedNeuronBuffer.Enqueue(i, addedNeuronGeneStruct);
}
//Assert.Fail();
}
/// <summary>
/// Performs an integrity check on the network definition.
/// Returns true if OK.
/// </summary>
public bool PerformIntegrityCheck()
{
// We will always have at least a bias and an output.
int count = _nodeList.Count;
if(count < 2) {
Debug.WriteLine(string.Format("Node list has less than the minimum number of neuron genes [{0}]", count));
return false;
}
// Check bias neuron.
if(NodeType.Bias != _nodeList[0].NodeType) {
Debug.WriteLine("Missing bias gene");
return false;
}
if(0u != _nodeList[0].Id) {
Debug.WriteLine(string.Format("Bias neuron ID != 0. [{0}]", _nodeList[0].Id));
return false;
}
// Check input nodes.
uint prevId = 0u;
int idx = 1;
for(int i=0; i<_inputNodeCount; i++, idx++)
{
if(NodeType.Input != _nodeList[idx].NodeType) {
Debug.WriteLine(string.Format("Invalid node type. Expected Input, got [{0}]", _nodeList[idx].NodeType));
return false;
}
if(_nodeList[idx].Id <= prevId) {
Debug.WriteLine("Input node is out of order and/or a duplicate.");
return false;
}
prevId = _nodeList[idx].Id;
}
// Check output neurons.
for(int i=0; i<_outputNodeCount; i++, idx++)
{
if(NodeType.Output != _nodeList[idx].NodeType) {
Debug.WriteLine(string.Format("Invalid node type. Expected Output, got [{0}]", _nodeList[idx].NodeType));
return false;
}
if(_nodeList[idx].Id <= prevId) {
Debug.WriteLine("Output node is out of order and/or a duplicate.");
return false;
}
prevId = _nodeList[idx].Id;
}
// Check hidden neurons.
// All remaining neurons should be hidden neurons.
for(; idx<count; idx++)
{
if(NodeType.Hidden != _nodeList[idx].NodeType) {
Debug.WriteLine(string.Format("Invalid node type. Expected Hidden, got [{0}]", _nodeList[idx].NodeType));
return false;
}
if(_nodeList[idx].Id <= prevId) {
Debug.WriteLine("Hidden node is out of order and/or a duplicate.");
return false;
}
prevId = _nodeList[idx].Id;
}
// Check connections.
count = _connectionList.Count;
if(0 == count)
{ // At least one connection is required, connectionless genomes are pointless.
Debug.WriteLine("Zero connections.");
return false;
}
// Check for multiple connections between nodes.
// Build a dictionary of connection endpoints.
Dictionary<ConnectionEndpointsStruct, object> endpointDict = new Dictionary<ConnectionEndpointsStruct,object>(count);
foreach(NetworkConnection conn in _connectionList)
{
ConnectionEndpointsStruct key = new ConnectionEndpointsStruct(conn.SourceNodeId, conn.TargetNodeId);
if(endpointDict.ContainsKey(key))
{
Debug.WriteLine("Connection error. A connection between the specified endpoints already exists.");
return false;
}
endpointDict.Add(key, null);
}
// Integrity check OK.
return true;
}
/// <summary>
/// Add a ConnectionGene to the builder, but only if the connection is not already present (as determined by it's neuron ID endpoints).
/// </summary>
/// <param name="connectionGene">The connection to add.</param>
/// <param name="parentGenome">The conenction's parent genome. This is used to obtain NeuronGene(s) for the connection endpoints.</param>
/// <param name="overwriteExisting">A flag that indicates if this connection should take precedence oevr an existing connection with
/// the same endpoints.</param>
public void TryAddGene(ConnectionGene connectionGene, NeatGenome parentGenome, bool overwriteExisting)
{
// Check if a matching gene has already been added.
ConnectionEndpointsStruct connectionKey = new ConnectionEndpointsStruct(connectionGene.SourceNodeId, connectionGene.TargetNodeId);
ConnectionGene existingConnectionGene;
if(!_connectionGeneDictionary.TryGetValue(connectionKey, out existingConnectionGene))
{ // Add new connection gene.
ConnectionGene connectionGeneCopy = new ConnectionGene(connectionGene);
_connectionGeneDictionary.Add(connectionKey, connectionGeneCopy);
// Insert connection gene into a list. Use more efficient approach (append to end) if we know the gene belongs at the end.
if(connectionGeneCopy.InnovationId > _highestConnectionGeneId) {
_connectionGeneList.Add(connectionGeneCopy);
_highestConnectionGeneId = connectionGeneCopy.InnovationId;
} else {
_connectionGeneList.InsertIntoPosition(connectionGeneCopy);
}
// Add neuron genes (if not already added).
// Source neuron.
NeuronGene srcNeuronGene;
if(!_neuronDictionary.TryGetValue(connectionGene.SourceNodeId, out srcNeuronGene))
{
srcNeuronGene = parentGenome.NeuronGeneList.GetNeuronById(connectionGene.SourceNodeId);
srcNeuronGene = new NeuronGene(srcNeuronGene, false); // Make a copy.
_neuronDictionary.Add(srcNeuronGene.Id, srcNeuronGene);
}
// Target neuron.
NeuronGene tgtNeuronGene;
if(!_neuronDictionary.TryGetValue(connectionGene.TargetNodeId, out tgtNeuronGene))
{
tgtNeuronGene = parentGenome.NeuronGeneList.GetNeuronById(connectionGene.TargetNodeId);
tgtNeuronGene = new NeuronGene(tgtNeuronGene, false); // Make a copy.
_neuronDictionary.Add(tgtNeuronGene.Id, tgtNeuronGene);
}
// Register connectivity with each neuron.
srcNeuronGene.TargetNeurons.Add(tgtNeuronGene.Id);
tgtNeuronGene.SourceNeurons.Add(srcNeuronGene.Id);
}
else if(overwriteExisting)
{ // The genome we are building already has a connection with the same neuron endpoints as the one we are
// trying to add. It didn't match up during correlation because it has a different innovation number, this
// is possible because the innovation history buffers throw away old innovations in a FIFO manner in order
// to prevent them from bloating.
// Here the 'overwriteExisting' flag is set so the gene we are currently trying to add is probably from the
// fitter parent, and therefore we want to use its connection weight in place of the existing gene's weight.
existingConnectionGene.Weight = connectionGene.Weight;
}
}
