//---------------------------------------------------------------------
IEnumerator <ActiveSite> IEnumerable <ActiveSite> .GetEnumerator()
{
// initialize and declare variables
areaSelected = 0;
double patchAreaSelected = 0;
List <ActiveSite> sites = stand.GetActiveSites(); // this stand's sites
Queue <ActiveSite> sitesToHarvest = new Queue <ActiveSite>(); // for harvesting
Queue <ActiveSite> sitesToConsider = new Queue <ActiveSite>(); // sites to harvest
Queue <ActiveSite> sitesConsidered = new Queue <ActiveSite>(); // all considered
Queue <ActiveSite> sitesToForbidAdjacency = new Queue <ActiveSite>(); // all sites harvested each patch which will be used to create borders around their neighbors
ActiveSite crntSite;
int random;
double standTargetArea = Model.Core.CellArea * stand.SiteCount * percent;
//get a random site from the stand
//random = (int) (Model.Core.GenerateUniform() *
// (stand.SiteCount - 1));
//get a random active site from the stand
random = (int)(Model.Core.GenerateUniform() * (sites.Count - 1));
crntSite = sites[random];
//while (!(((Site)crntSite).IsActive) && sites.Count > 0) {
//while (sites.Count > 0) {
// //Model.Core.UI.WriteLine(" ERROR: Non-active site included in stand {0}.", stand.MapCode);
// sitesConsidered.Enqueue(crntSite);
// sites.Remove(crntSite);
// random = (int)(Model.Core.GenerateUniform() * (sites.Count - 1));
// crntSite = sites[random];
//} // while (!(((Site)crntSite).IsActive) && sites.Count > 0)
//put initial pivot site on queue
sitesToConsider.Enqueue(crntSite);
sites.Remove(crntSite);
// loop through stand, harvesting patches of size patch_size at a time
while (areaSelected < standTargetArea && sites.Count > 0)
{
while (patchAreaSelected < patch_size &&
areaSelected < standTargetArea &&
sites.Count > 0)
{
//loop through the site's neighbors enqueueing them too
foreach (RelativeLocation loc in all_neighbor_locations)
{
// get a neighbor site
Site tempSite = crntSite.GetNeighbor(loc);
if (tempSite != null && tempSite.IsActive)
{
ActiveSite nbrSite = (ActiveSite)tempSite;
if (sites.Contains(nbrSite))
{
//get a neighbor site (if it's non-null and active)
if (!sitesToConsider.Contains(nbrSite) &&
!sitesConsidered.Contains(nbrSite))
{
//then enqueue the neighbor
sitesToConsider.Enqueue(nbrSite);
}
//Always remove the site if it's in the sites list.
sites.Remove(nbrSite);
}
}
}
//check if there's anything left on the queue
if (sitesToConsider.Count > 1)
{
ActiveSite crntConsideredSite = sitesToConsider.Dequeue();
if (SiteVars.TimeSinceLastDamage(crntConsideredSite) >=
stand.MinTimeSinceDamage)
{
// now after looping through all of the current
// site's neighbors dequeue the current site and
// put it on the sitesToHarvest queue (used later)
sitesToHarvest.Enqueue(crntConsideredSite);
sitesToForbidAdjacency.Enqueue(crntConsideredSite);
// increment area selected and total_areaSelected
patchAreaSelected += Model.Core.CellArea;
areaSelected += Model.Core.CellArea;
}
// Whether harvestable or not, it has been considered
sitesConsidered.Enqueue(crntConsideredSite);
//and set the new crntSite to the head of the queue (by peeking)
crntSite = sitesToConsider.Peek();
}
else if (sitesToConsider.Count == 1) //get another site from the queue
{
crntSite = sitesToConsider.Peek();
ActiveSite crntConsideredSite = sitesToConsider.Dequeue();
if (SiteVars.TimeSinceLastDamage(crntConsideredSite) >=
stand.MinTimeSinceDamage)
{
sitesToHarvest.Enqueue(crntConsideredSite);
sitesToForbidAdjacency.Enqueue(crntConsideredSite);
//increment area selected and total_areaSelected
patchAreaSelected += Model.Core.CellArea;
areaSelected += Model.Core.CellArea;
}
// Whether harvestable or not, it has been considered
sitesConsidered.Enqueue(crntConsideredSite);
}
else
{
// else just break out- if it's not big enough it's not big enough
//Model.Core.UI.WriteLine("patch isn't big enough ({0}), must BREAK.", areaSelected);
break;
} // if (sitesToConsider.Count > 1)
} // while (patchAreaSelected < patch_size &&
//Model.Core.UI.WriteLine("Done with a patch.");
// Always put the considered sites back in to the list so they can be considered again
if (sitesToConsider.Count > 0)
{
ActiveSite[] remainingSitesToConsider = sitesToConsider.ToArray();
sites.AddRange(remainingSitesToConsider);
}
// Create a border around each patch which will forbid its neighbors from being harvested
if (!allowOverlap)
{
while (sitesToForbidAdjacency.Count > 0)
{
ActiveSite site = sitesToForbidAdjacency.Dequeue();
foreach (RelativeLocation loc in all_neighbor_locations)
{
Site tempSite = site.GetNeighbor(loc);
if (tempSite != null && tempSite.IsActive)
{
ActiveSite nbrSite = (ActiveSite)tempSite;
// Do not cut sites which are adjacent to sites that will be harvested
if (!sitesToHarvest.Contains(nbrSite))
{
sites.Remove(nbrSite);
}
}
}
}
}
//clear the sitesToConsider queue to get rid of old sites
sitesToConsider.Clear();
sitesToForbidAdjacency.Clear();
// get a new random site to start at (one that hasn't been
// put on the sitesConsidered queue yet)
// only allow a site-count # of tries
bool found_site = false;
int tries = 0;
while (!found_site && tries < sites.Count)
{
//increment the number of tries
tries++;
random = (int)(Model.Core.GenerateUniform() * (sites.Count - 1));
crntSite = sites[random];
// Get an active site
//while (!(((Site)crntSite).IsActive) && sites.Count > 0) {
//while (sites.Count > 0) {
//Model.Core.UI.WriteLine(" ERROR: Non-active site included in stand {0}.", stand.MapCode);
// sitesConsidered.Enqueue(crntSite);
// sites.Remove(crntSite);
// random = (int)(Model.Core.GenerateUniform() *
// (sites.Count - 1));
// crntSite = sites[random];
//} // while (!(((Site)crntSite).IsActive) && sites.Count > 0)
if (sites.Count <= 0)
{
break;
}
//if it's not on the sitesConsidered queue already
if (!sitesConsidered.Contains(crntSite))
{
// now put this site on for consideration (which will
// later be put onto the sitesToHarvest queue).
sitesToConsider.Enqueue(crntSite);
sites.Remove(crntSite);
found_site = true;
}
} // while (!found_site && tries < sites.Count)
//if the site isn't found (prev loop was broken because
// of too many tries) then break from this stand entirely
if (!found_site)
{
break;
}
//reset areaSelected = 0 to start over
patchAreaSelected = 0;
//Model.Core.UI.WriteLine("areaSelected = {0}", areaSelected);
} // while (areaSelected < standTargetArea && sites.Count > 0)
// if the stand met the criteria for the harvest, mark it
// as harvested otherwise add the prescription name to the
// stands rejected prescription list
if (areaSelected > 0)
{
stand.MarkAsHarvested();
stand.EventId = EventId.MakeNewId();
}
else
{
//Model.Core.UI.WriteLine("Rejecting stand {0} for prescription {1}",stand.MapCode, stand.PrescriptionName);
stand.RejectPrescriptionName(stand.PrescriptionName);
}
// even if patches do not reach target percentage, harvest what we can
if (areaSelected > 0)
{
while (sitesToHarvest.Count > 0)
{
yield return(sitesToHarvest.Dequeue());
}
}
} // IEnumerator<ActiveSite> IEnumerable<ActiveSite>.GetEnumerator()
