Node *treeMakeMinus(Node **node)
{
Node *tmpNode = NULL;
tmpNode = treeNodeCreate();
tmpNode->_left = treeNodeCreate();
tmpNode->_right = treeCopy(node);
tmpNode->_varOp = '-';
free(*node);
*node = NULL;
return tmpNode;
}
Node *treeCopy(Node **node)
{
Node *tmpNode = NULL;
if (*node == NULL)
return NULL;
tmpNode = treeNodeCreate();
tmpNode->_varOp = (*node)->_varOp;
tmpNode->_num = (*node)->_num;
tmpNode->_left = treeCopy(&(*node)->_left);
tmpNode->_right = treeCopy(&(*node)->_right);
return tmpNode;
}
treeObj *msCreateTree(shapefileObj *shapefile, int maxdepth)
{
int i;
treeObj *tree;
rectObj bounds;
if(!shapefile) return NULL;
/* -------------------------------------------------------------------- */
/* Allocate the tree object */
/* -------------------------------------------------------------------- */
tree = (treeObj *) msSmallMalloc(sizeof(treeObj));
tree->numshapes = shapefile->numshapes;
tree->maxdepth = maxdepth;
/* -------------------------------------------------------------------- */
/* If no max depth was defined, try to select a reasonable one */
/* that implies approximately 8 shapes per node. */
/* -------------------------------------------------------------------- */
if( tree->maxdepth == 0 ) {
int numnodes = 1;
while(numnodes*4 < shapefile->numshapes) {
tree->maxdepth += 1;
numnodes = numnodes * 2;
}
}
/* -------------------------------------------------------------------- */
/* Allocate the root node. */
/* -------------------------------------------------------------------- */
tree->root = treeNodeCreate(shapefile->bounds);
for(i=0; i<shapefile->numshapes; i++) {
if(msSHPReadBounds(shapefile->hSHP, i, &bounds) == MS_SUCCESS)
treeAddShapeId(tree, i, bounds);
}
return tree;
}
void treeBuild(Node **node, Stack *st)
{
Token token;
if (stackEmpty(st))
return;
token = stackTop(st);
stackPop(st);
(*node) = treeNodeCreate();
(*node)->_varOp = token._varOp;
(*node)->_num = token._num;
if (isOp((*node)->_varOp))
{
treeBuild(&(*node)->_right, st);
treeBuild(&(*node)->_left, st);
}
}
static int treeNodeAddShapeId( treeNodeObj *node, int id, rectObj rect, int maxdepth)
{
int i;
/* -------------------------------------------------------------------- */
/* If there are subnodes, then consider whether this object */
/* will fit in them. */
/* -------------------------------------------------------------------- */
if( maxdepth > 1 && node->numsubnodes > 0 ) {
for(i=0; i<node->numsubnodes; i++ ) {
if( msRectContained(&rect, &node->subnode[i]->rect)) {
return treeNodeAddShapeId( node->subnode[i], id, rect, maxdepth-1);
}
}
}
/* -------------------------------------------------------------------- */
/* Otherwise, consider creating four subnodes if could fit into */
/* them, and adding to the appropriate subnode. */
/* -------------------------------------------------------------------- */
#if MAX_SUBNODES == 4
else if( maxdepth > 1 && node->numsubnodes == 0 ) {
rectObj half1, half2, quad1, quad2, quad3, quad4;
treeSplitBounds(&node->rect, &half1, &half2);
treeSplitBounds(&half1, &quad1, &quad2);
treeSplitBounds(&half2, &quad3, &quad4);
if(msRectContained(&rect, &quad1) || msRectContained(&rect, &quad2) || msRectContained(&rect, &quad3) || msRectContained(&rect, &quad4)) {
node->numsubnodes = 4;
node->subnode[0] = treeNodeCreate(quad1);
node->subnode[1] = treeNodeCreate(quad2);
node->subnode[2] = treeNodeCreate(quad3);
node->subnode[3] = treeNodeCreate(quad4);
/* recurse back on this node now that it has subnodes */
return(treeNodeAddShapeId(node, id, rect, maxdepth));
}
}
#endif
/* -------------------------------------------------------------------- */
/* Otherwise, consider creating two subnodes if could fit into */
/* them, and adding to the appropriate subnode. */
/* -------------------------------------------------------------------- */
#if MAX_SUBNODE == 2
else if( maxdepth > 1 && node->numsubnodes == 0 ) {
rectObj half1, half2;
treeSplitBounds(&node->rect, &half1, &half2);
if( msRectContained(&rect, &half1)) {
node->numsubnodes = 2;
node->subnode[0] = treeNodeCreate(half1);
node->subnode[1] = treeNodeCreate(half2);
return(treeNodeAddShapeId(node->subnode[0], id, rect, maxdepth-1));
} else if(msRectContained(&rect, &half2)) {
node->numsubnodes = 2;
node->subnode[0] = treeNodeCreate(&half1);
node->subnode[1] = treeNodeCreate(&half2);
return(treeNodeAddShapeId(node->subnode[1], id, rect, maxdepth-1));
}
}
#endif /* MAX_SUBNODE == 2 */
/* -------------------------------------------------------------------- */
/* If none of that worked, just add it to this nodes list. */
/* -------------------------------------------------------------------- */
node->numshapes++;
node->ids = SfRealloc( node->ids, sizeof(ms_int32) * node->numshapes );
node->ids[node->numshapes-1] = id;
return MS_TRUE;
}
