private void TryAndStackItemsIntoSpace(PackedLayer layer,
PackedItem prevItem,
ItemList nextItems,
int maxWidth,
int maxLength,
int maxDepth,
int x,
int y,
int z,
int rowLength
)
{
while (items.Count() > 0 && CheckNonDimensionalConstraints(items.Top()))
{
var stackedItem = GetOrientationForItem(
items.Top(),
prevItem,
nextItems,
items.Count == 1,
maxWidth,
maxLength,
maxDepth,
rowLength,
x,
y,
z
);
if (stackedItem != null)
{
remainingWeight -= items.Top().Weight;
layer.Insert(PackedItem.FromOrientatedItem(stackedItem, x, y, z));
items.Extract();
maxDepth -= stackedItem.Depth;
z += stackedItem.Depth;
}
else
{
break;
}
}
}
/// <summary>
/// Pack items into an individual vertical layer.
/// </summary>
/// <param name="startDepth"></param>
/// <param name="widthLeft"></param>
/// <param name="lengthLeft"></param>
/// <param name="depthLeft"></param>
protected void PackLayer(int startDepth, int widthLeft, int lengthLeft, int depthLeft)
{
var newLayer = new PackedLayer();
layers.Add(newLayer);
int x, y, rowWidth, rowLength, layerDepth;
x = y = rowWidth = rowLength = layerDepth = 0;
PackedItem prevItem = null;
while (items.Count > 0)
{
var itemToPack = items.Extract();
//skip items that are simply too heavy or too large
if (!CheckNonDimensionalConstraints(itemToPack))
{
RebuildItemList();
continue;
}
var orientedItem = GetOrientationForItem(itemToPack,
prevItem,
items,
!HasItemsLeftToPack(),
widthLeft,
lengthLeft,
depthLeft,
rowLength,
x,
y,
startDepth
);
if (orientedItem != null)
{
var packedItem = PackedItem.FromOrientatedItem(orientedItem, x, y, startDepth);
newLayer.Insert(packedItem);
remainingWeight -= orientedItem.Item.Weight;
widthLeft -= orientedItem.Width;
rowWidth += orientedItem.Width;
rowLength = Math.Max(rowLength, orientedItem.Length);
layerDepth = Math.Max(layerDepth, orientedItem.Depth);
//allow items to be stacked in place within the same footprint up to current layer depth
var stackableDepth = layerDepth - orientedItem.Depth;
TryAndStackItemsIntoSpace(newLayer,
prevItem,
items,
orientedItem.Width,
orientedItem.Length,
stackableDepth,
x,
y,
startDepth + orientedItem.Depth,
rowLength
);
x += orientedItem.Width;
prevItem = packedItem;
if (items.Count == 0)
{
RebuildItemList();
}
}
else if (newLayer.Items.Count == 0)
{
// zero items on layer
// doesn't fit on layer even when empty, skipping for good
continue;
}
else if (widthLeft > 0 && items.Count > 0)
{
// skip for now, move on to the next item
skippedItems.Add(itemToPack);
// abandon here if next item is the same, no point trying to keep going. Last time is not skipped, need that to trigger appropriate reset logic
while (items.Count > 2 && orientatedItemFactory.IsSameDimensions(itemToPack, items.Top()))
{
this.skippedItems.Add(items.Extract());
}
}
else if (x > 0 && lengthLeft >= Math.Min(Math.Min(itemToPack.Width, itemToPack.Length), itemToPack.Depth))
{
// No more fit in width wise, resetting for new row
widthLeft += rowWidth;
lengthLeft -= rowLength;
y += rowLength;
x = rowWidth = rowLength = 0;
skippedItems.Add(itemToPack);
RebuildItemList();
prevItem = null;
continue;
}
else
{
// no items fit, so starting next vertical layer
skippedItems.Add(itemToPack);
RebuildItemList();
return;
}
}
}