/*
* Add a branch to a node. Split the node if necessary.
* Returns 0 if node not split. Old node updated.
* Returns 1 if node split, sets *new_node to address of new node.
* Old node updated, becomes one of two.
* Returns 2 if branches were removed for forced reinsertion
*/
int RTreeAddBranch(struct RTree_Branch *b, struct RTree_Node *n,
struct RTree_Node **newnode, struct RTree_ListBranch **ee,
struct RTree_Rect *cover, int *overflow, struct RTree *t)
{
int i, maxkids;
maxkids = MAXKIDS((n)->level, t);
if (n->count < maxkids) { /* split won't be necessary */
if ((n)->level > 0) { /* internal node */
for (i = 0; i < maxkids; i++) { /* find empty branch */
if (!t->valid_child(&(n->branch[i].child))) {
n->branch[i] = *b;
n->count++;
break;
}
}
return 0;
}
else if ((n)->level == 0) { /* leaf */
for (i = 0; i < maxkids; i++) { /* find empty branch */
if (n->branch[i].child.id == 0) {
n->branch[i] = *b;
n->count++;
break;
}
}
return 0;
}
}
else {
if (n->level < t->rootlevel && overflow[n->level]) {
/* R*-tree forced reinsert */
RTreeRemoveBranches(n, b, ee, cover, t);
overflow[n->level] = 0;
return 2;
}
else {
if (t->fd > -1)
RTreeInitNode(*newnode, NODETYPE(n->level, t->fd));
else
*newnode = RTreeNewNode(t, (n)->level);
RTreeSplitNode(n, b, *newnode, t);
return 1;
}
}
/* should not be reached */
assert(0);
return -1;
}
static int RTreeAddBranch(node_t n, branch_t b, node_t *new_node)
{
int i;
assert(n);
if (n->count < MAXCARD) /*split not necessary*/
{
for (i = 0; i < MAXCARD; i++)
if (n->branch[i].child == NULL)
{
n->branch[i] = b;
n->count ++;
break;
}
return FALSE;
}
else /*needs to split*/
{
assert(new_node);
RTreeSplitNode (n, b, new_node);
return TRUE;
}
}
