public virtual void Clear()
{
if (root != null)
{
root.Purge(height);
root = null;
}
height = 0;
n = 0;
Modify();
}
internal RtreePage(Storage storage, RtreePage root, RtreePage p)
{
branch = storage.CreateLink(card);
branch.Size = card;
b = new Rectangle[card];
n = 2;
SetBranch(0, root.Cover(), root);
SetBranch(1, p.Cover(), p);
for (int i = 2; i < card; i++)
{
b[i] = new Rectangle();
}
}
internal RtreePage SplitPage(Storage storage, Rectangle r, IPersistent obj)
{
int i, j, seed0 = 0, seed1 = 0;
long[] rectArea = new long[card + 1];
long waste;
long worstWaste = Int64.MinValue;
//
// As the seeds for the two groups, find two rectangles which waste
// the most area if covered by a single rectangle.
//
rectArea[0] = r.Area();
for (i = 0; i < card; i++)
{
rectArea[i + 1] = b[i].Area();
}
Rectangle bp = r;
for (i = 0; i < card; i++)
{
for (j = i + 1; j <= card; j++)
{
waste = Rectangle.JoinArea(bp, b[j - 1]) - rectArea[i] - rectArea[j];
if (waste > worstWaste)
{
worstWaste = waste;
seed0 = i;
seed1 = j;
}
}
bp = b[i];
}
byte[] taken = new byte[card];
Rectangle group0, group1;
long groupArea0, groupArea1;
int groupCard0, groupCard1;
RtreePage pg;
taken[seed1 - 1] = 2;
group1 = new Rectangle(b[seed1 - 1]);
if (seed0 == 0)
{
group0 = new Rectangle(r);
pg = new RtreePage(storage, obj, r);
}
else
{
group0 = new Rectangle(b[seed0 - 1]);
pg = new RtreePage(storage, branch.GetRaw(seed0 - 1), group0);
SetBranch(seed0 - 1, r, obj);
}
groupCard0 = groupCard1 = 1;
groupArea0 = rectArea[seed0];
groupArea1 = rectArea[seed1];
//
// Split remaining rectangles between two groups.
// The one chosen is the one with the greatest difference in area
// expansion depending on which group - the rect most strongly
// attracted to one group and repelled from the other.
//
while (groupCard0 + groupCard1 < card + 1 && groupCard0 < card + 1 - minFill && groupCard1 < card + 1 - minFill)
{
int betterGroup = -1, chosen = -1;
long biggestDiff = -1;
for (i = 0; i < card; i++)
{
if (taken[i] == 0)
{
long diff = (Rectangle.JoinArea(group0, b[i]) - groupArea0) - (Rectangle.JoinArea(group1, b[i]) - groupArea1);
if (diff > biggestDiff || -diff > biggestDiff)
{
chosen = i;
if (diff < 0)
{
betterGroup = 0;
biggestDiff = -diff;
}
else
{
betterGroup = 1;
biggestDiff = diff;
}
}
}
}
Assert.That(chosen >= 0);
if (betterGroup == 0)
{
group0.Join(b[chosen]);
groupArea0 = group0.Area();
taken[chosen] = 1;
pg.SetBranch(groupCard0++, b[chosen], branch.GetRaw(chosen));
}
else
{
groupCard1 += 1;
group1.Join(b[chosen]);
groupArea1 = group1.Area();
taken[chosen] = 2;
}
}
// If one group gets too full, then remaining rectangle are
// split between two groups in such way to balance cards of two groups.
if (groupCard0 + groupCard1 < card + 1)
{
for (i = 0; i < card; i++)
{
if (taken[i] == 0)
{
if (groupCard0 >= groupCard1)
{
taken[i] = 2;
groupCard1 += 1;
}
else
{
taken[i] = 1;
pg.SetBranch(groupCard0++, b[i], branch.GetRaw(i));
}
}
}
}
pg.n = groupCard0;
n = groupCard1;
for (i = 0, j = 0; i < groupCard1; j++)
{
if (taken[j] == 2)
{
SetBranch(i++, b[j], branch.GetRaw(j));
}
}
return pg;
}
private bool GotoFirstItem(int sp, RtreePage pg)
{
for (int i = 0, n = pg.n; i < n; i++)
{
if (r.Intersects(pg.b[i]))
{
if (sp + 1 == Enclosing_Instance.height || GotoFirstItem(sp + 1, (RtreePage) pg.branch.Get(i)))
{
pageStack[sp] = pg;
posStack[sp] = i;
return true;
}
}
}
return false;
}
internal RtreeEntry(RtreePage pg, int pos)
{
this.pg = pg;
this.pos = pos;
}
public virtual void Remove(Rectangle r, IPersistent obj)
{
if (root == null)
{
throw new StorageError(StorageError.KEY_NOT_FOUND);
}
ArrayList reinsertList = new ArrayList();
int reinsertLevel = root.Remove(r, obj, height, reinsertList);
if (reinsertLevel < 0)
{
throw new StorageError(StorageError.KEY_NOT_FOUND);
}
for (int i = reinsertList.Count; --i >= 0; )
{
RtreePage p = (RtreePage) reinsertList[i];
for (int j = 0, n2 = p.n; j < n2; j++)
{
RtreePage q = root.Insert(Storage, p.b[j], p.branch.Get(j), height - reinsertLevel);
if (q != null)
{
// root split
root = new RtreePage(Storage, root, q);
height += 1;
}
}
reinsertLevel -= 1;
p.Deallocate();
}
if (root.n == 1 && height > 1)
{
RtreePage newRoot = (RtreePage) root.branch.Get(0);
root.Deallocate();
root = newRoot;
height -= 1;
}
n -= 1;
updateCounter += 1;
Modify();
}
public virtual void Put(Rectangle r, IPersistent obj)
{
if (root == null)
{
root = new RtreePage(Storage, obj, r);
height = 1;
}
else
{
RtreePage p = root.Insert(Storage, r, obj, height);
if (p != null)
{
root = new RtreePage(Storage, root, p);
height += 1;
}
}
updateCounter += 1;
n += 1;
Modify();
}
