/// <summary>
/// Create a directed graph based on the provided connections (between node IDs) and a predefined set of input/output
/// node IDs defined as being in a contiguous sequence starting at ID zero.
/// </summary>
/// <param name="connections">The connections that define the structure and weights of the weighted directed graph.</param>
/// <param name="inputCount">Input node count.</param>
/// <param name="outputCount">Output node count.</param>
/// <returns>A new instance of <see cref="DirectedGraph"/>.</returns>
/// <remarks>
/// <paramref name="connections"/> is required to be sorted by sourceId, TargetId.
/// </remarks>
public static DirectedGraph Create(
Span <DirectedConnection> connections,
int inputCount, int outputCount)
{
// Debug assert that the connections are sorted.
Debug.Assert(SortUtils.IsSortedAscending <DirectedConnection>(connections));
// Determine the full set of hidden node IDs.
int inputOutputCount = inputCount + outputCount;
var hiddenNodeIdArr = GetHiddenNodeIdArray(connections, inputOutputCount);
// Compile a mapping from current nodeIDs to new IDs (i.e. removing gaps in the ID space).
INodeIdMap nodeIdMap = DirectedGraphBuilderUtils.CompileNodeIdMap(
inputOutputCount, hiddenNodeIdArr);
// Extract/copy the neat genome connectivity graph into an array of DirectedConnection.
// Notes.
// The array contents will be manipulated, so copying this avoids modification of the genome's
// connection gene list.
// The IDs are substituted for node indexes here.
ConnectionIds connIds = CopyAndMapIds(connections, nodeIdMap);
// Construct and return a new DirectedGraph.
int totalNodeCount = inputOutputCount + hiddenNodeIdArr.Length;
return(new DirectedGraph(inputCount, outputCount, totalNodeCount, connIds));
}
/// <summary>
/// Create a NeatGenome with the given meta data, connection genes and supplementary data.
/// </summary>
/// <param name="id">Genome ID.</param>
/// <param name="birthGeneration">Birth generation.</param>
/// <param name="connGenes">Connection genes.</param>
/// <param name="hiddenNodeIdArr">An array of the hidden node IDs in the genome, in ascending order.</param>
/// <returns>A new NeatGenome instance.</returns>
public NeatGenome <T> Create(
int id, int birthGeneration,
ConnectionGenes <T> connGenes,
int[] hiddenNodeIdArr)
{
// Create a mapping from node IDs to node indexes.
INodeIdMap nodeIndexByIdMap = DirectedGraphBuilderUtils.CompileNodeIdMap(
_metaNeatGenome.InputOutputNodeCount, hiddenNodeIdArr);
return(Create(id, birthGeneration, connGenes, hiddenNodeIdArr, nodeIndexByIdMap));
}