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/****************************************************************************
* MODULE: R-Tree library
*
* AUTHOR(S): Antonin Guttman - original code
* Daniel Green (green@superliminal.com) - major clean-up
* and implementation of bounding spheres
*
* PURPOSE: Multidimensional index
*
* COPYRIGHT: (C) 2001 by the GRASS Development Team
*
* This program is free software under the GNU General Public
* License (>=v2). Read the file COPYING that comes with GRASS
* for details.
*****************************************************************************/
#include <stdio.h>
#include "index.h"
struct Rect rects[] = {
{{0, 0, 0, 2, 2,
0}}, /* xmin, ymin, zmin, xmax, ymax, zmax (for 3 dimensional RTree) */
{{5, 5, 0, 7, 7, 0}},
{{8, 5, 0, 9, 6, 0}},
{{7, 1, 0, 9, 2, 0}}};
int nrects = sizeof(rects) / sizeof(rects[0]);
struct Rect search_rect = {
{6, 4, 0, 10, 6,
0} /* search will find above rects that this one overlaps */
};
int MySearchCallback(int id, void *arg)
{
/* Note: -1 to make up for the +1 when data was inserted */
fprintf(stdout, "Hit data rect %d\n", id - 1);
return 1; /* keep going */
}
int main()
{
struct RTree *rtree = RTreeNewIndex(2);
int i, nhits;
fprintf(stdout, "nrects = %d\n", nrects);
/*
* Insert all the data rects.
* Notes about the arguments:
* parameter 1 is the rect being inserted,
* parameter 2 is its ID. NOTE: *** ID MUST NEVER BE ZERO ***, hence the +1,
* parameter 3 is the root of the tree. Note: its address is passed
* because it can change as a result of this call, therefore no other parts
* of this code should stash its address since it could change undernieth.
* parameter 4 is always zero which means to add from the root.
*/
for (i = 0; i < nrects; i++)
RTreeInsertRect(&rects[i], i + 1, rtree); /* i+1 is rect ID. */
nhits = RTreeSearch(rtree, &search_rect, MySearchCallback, 0);
fprintf(stdout, "Search resulted in %d hits\n", nhits);
return 0;
}
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