/// <summary>
/// Solves the instance
/// </summary>
protected override void Solve()
{
// Initialize meta-info
VolumeOfContainers = Instance.Containers.Sum(c => c.Mesh.Volume);
// Init ordering
List <Container> containers = null;
List <VariablePiece> pieces = null;
int[][] orientationsPerPiece = null;
Init(out containers, out pieces, out orientationsPerPiece);
// Generate initial solution
ExtremePointInsertion(Solution, containers, pieces, orientationsPerPiece);
// Improve solution
if (Config.Improvement)
{
// Log visual
LogVisuals(Solution, true);
// Improve
Solution = GASP(Solution, containers, pieces, orientationsPerPiece, ExtremePointInsertion);
}
// Log
if (Config.Log != null)
{
Config.Log("EPs available: " + Solution.ExtremePoints.Sum(kvp => kvp.Count) + "\n");
Config.Log(Solution.VolumeContained.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + " / " +
VolumeOfContainers.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + "\n");
}
}
/// <summary>
/// Logs basic information about the progress
/// </summary>
/// <param name="piece">The currently added piece</param>
/// <param name="container">The container to which the piece is added</param>
protected void LogProgress(COSolution solution, Piece piece, Container container)
{
if (Config.Log != null && DateTime.Now.Ticks - LogOldMillis > 10000000)
{
LogOldMillis = DateTime.Now.Ticks;
Config.Log(solution.ExploitedVolume.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + " / " +
VolumeOfContainers.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) +
" - Piece " + piece.ID + " -> Container " + container.ID + "\n");
}
}
protected override void Solve()
{
// --> Initialization
// Initialize meta-info
VolumeOfContainers = Instance.Containers.Sum(c => c.Mesh.Volume);
// Init ordering
List <VariablePiece> pieces = null;
Init(out Solution.ConstructionContainerOrder, out pieces, out Solution.ConstructionOrientationOrder);
// --> Construction part
// Log
Config.Log?.Invoke("Starting construction ... " + Environment.NewLine);
// Generate initial solution
ExtremePointInsertion(Solution, Solution.ConstructionContainerOrder, pieces, Solution.ConstructionOrientationOrder);
// --> Improvement part
// Log
Config.Log?.Invoke("Starting improvement ... " + Environment.NewLine);
// Measure performance compared to given solution
double initialExploitedVolume = Solution.ExploitedVolume;
// TODO move the following into the config
int intervalIterationCountMax = 100;
double alpha = 0.9;
// Init counters
int currentIteration = 0;
int lastImprovement = 0;
double currentTemperature = 1000;
int currentIntervalIteration = 0;
// Init solutions
COSolution acceptedSolution = Solution.Clone();
// Main loop
do
{
// Init solution for this turn
COSolution currentSolution = acceptedSolution.Clone();
// Destroy the solution
ALNSDestroy(currentSolution);
// Repair the solution
ALNSRepair(currentSolution);
// Check whether we want to accept the solution or discard it
if (ALNSAccept(acceptedSolution.ExploitedVolume, currentSolution.ExploitedVolume, Solution.ExploitedVolume, currentTemperature))
{
acceptedSolution = currentSolution;
}
// Lower temperature if iteration limit is reached
if (currentIntervalIteration >= intervalIterationCountMax)
{
currentIntervalIteration = 0;
currentTemperature *= alpha;
}
// Store every new best solution
if (acceptedSolution.ExploitedVolume > Solution.ExploitedVolume)
{
Solution = acceptedSolution;
}
// Log visuals
LogVisuals(Solution, false);
// Log
if (DateTime.Now.Ticks - LogOldMillis > 1000000)
{
LogOldMillis = DateTime.Now.Ticks;
Config.Log?.Invoke(currentIteration + ". " +
Solution.ExploitedVolume.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + " / " +
VolumeOfContainers.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) +
" (" + (Solution.ExploitedVolume / VolumeOfContainers * 100).ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + " %) - Current: " +
acceptedSolution.ExploitedVolume.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + " / " +
VolumeOfContainers.ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) +
" (" + ((Solution.ExploitedVolume / VolumeOfContainers - initialExploitedVolume / VolumeOfContainers) * 100).ToString(ExportationConstants.EXPORT_FORMAT_SHORT, ExportationConstants.FORMATTER) + " %)" +
" Time: " + (DateTime.Now - Config.StartTimeStamp).TotalSeconds +
" \n");
Config.LogSolutionStatus?.Invoke((DateTime.Now - Config.StartTimeStamp).TotalSeconds, Solution.ExploitedVolume);
}
// Update counters
currentIteration++;
currentIntervalIteration++;
} while (currentIteration - lastImprovement < Config.StagnationDistance && !Cancelled && !TimeUp);
}
