public DistanceItem()
{
Item1 = new ItemBin();
Item2 = new ItemBin();
SquareDistance = 0;
Distance = 0;
}
public DistanceItem(ItemBin bin1, ItemBin bin2)
{
Item1 = bin1;
Item2 = bin2;
SquareDistance = Item1.Location.GetSquareDistance(Item2.Location);
Distance = System.Math.Sqrt(SquareDistance);
}
public Route(ItemBin bin, double dist = 0)
{
StartPoint = bin;
Length = dist;
}
public Route()
{
StartPoint = new ItemBin();
Length = 0;
}
private List <Route> NearestAddition(Request request)
{
// Initial result contains the starting position of the robot ang route length 0
var result = new List <Route>()
{
new Route()
};
if (request.Targets.Count > 0)
{
// Create copy of targets so that the original version doesn't change
var targets = new List <int>();
request.Targets.ForEach(t => targets.Add(t));
// Go through the current route and find the nearest requested bin to add
// Add first target
ItemBin currentBestBin = null;
DistanceItem currentBestDistance = null;
foreach (var target in targets)
{
var bin = Layout.ItemBins.Find(b => b.Identifier == target);
var distanceItem = Layout.DistanceTable.Find(d => (d.Item1.Identifier == 0 && d.Item2.Identifier == target) || (d.Item1.Identifier == target && d.Item2.Identifier == 0));
if (bin != null && distanceItem != null && (currentBestDistance == null || distanceItem.SquareDistance < currentBestDistance.SquareDistance))
{
currentBestBin = bin;
currentBestDistance = distanceItem;
}
}
if (currentBestBin != null && currentBestDistance != null)
{
// Update distance to adjacent bin
result[0].Length = currentBestDistance.Distance;
// Add new bin
result.Add(new Route(currentBestBin, currentBestDistance.Distance));
// Remove found target
targets.RemoveAll(t => t == currentBestBin.Identifier);
}
var allTargetsAdded = (targets.Count == 0);
while (!allTargetsAdded)
{
currentBestBin = null;
DistanceItem distLeft = null;
DistanceItem distRight = null;
DistanceItem currentBestLeft = null;
DistanceItem currentBestRight = null;
double currentBestAddedDistance = -1;
int currentPosToAdd = -1;
for (int i = 0; i < result.Count; i++)
{
// For each pair of adjacent points in the route,
// find a target that increases the route distance the least
var currentRouteItem = result[i];
var nextRouteItem = (i + 1 >= result.Count) ? result[0] : result[i + 1];
foreach (var target in targets)
{
// Fing the nearest target for this pair
distLeft = Layout.DistanceTable.Find(d => (d.Item1.Identifier == currentRouteItem.StartPoint.Identifier && d.Item2.Identifier == target) ||
(d.Item1.Identifier == target && d.Item2.Identifier == currentRouteItem.StartPoint.Identifier));
distRight = Layout.DistanceTable.Find(d => (d.Item1.Identifier == nextRouteItem.StartPoint.Identifier && d.Item2.Identifier == target) ||
(d.Item1.Identifier == target && d.Item2.Identifier == nextRouteItem.StartPoint.Identifier));
if (currentBestAddedDistance < 0 || currentBestAddedDistance > (distLeft.Distance + distRight.Distance - currentRouteItem.Length))
{
currentPosToAdd = i;
currentBestAddedDistance = distLeft.Distance + distRight.Distance - currentRouteItem.Length;
currentBestBin = (distLeft.Item1.Identifier == target) ? distLeft.Item1 : distLeft.Item2;
currentBestLeft = distLeft;
currentBestRight = distRight;
}
}
}
if (currentBestBin != null && currentBestLeft != null && currentBestRight != null &&
currentBestAddedDistance > -1 && currentPosToAdd >= 0)
{
// Update distance to adjacent bin
result[currentPosToAdd].Length = currentBestLeft.Distance;
// Add new bin between i and i + 1
result.Insert(currentPosToAdd + 1, new Route(currentBestBin, currentBestRight.Distance));
// Remove found target
targets.RemoveAll(t => t == currentBestBin.Identifier);
}
allTargetsAdded = (targets.Count == 0);
}
}
return(result);
}
