SHPCreateTree( SHPHandle hSHP, int nDimension, int nMaxDepth,
double *padfBoundsMin, double *padfBoundsMax )
{
SHPTree *psTree;
if( padfBoundsMin == NULL && hSHP == NULL )
return NULL;
/* -------------------------------------------------------------------- */
/* Allocate the tree object */
/* -------------------------------------------------------------------- */
psTree = (SHPTree *) malloc(sizeof(SHPTree));
psTree->hSHP = hSHP;
psTree->nMaxDepth = nMaxDepth;
psTree->nDimension = nDimension;
/* -------------------------------------------------------------------- */
/* If no max depth was defined, try to select a reasonable one */
/* that implies approximately 8 shapes per node. */
/* -------------------------------------------------------------------- */
if( psTree->nMaxDepth == 0 && hSHP != NULL )
{
int nMaxNodeCount = 1;
int nShapeCount;
SHPGetInfo( hSHP, &nShapeCount, NULL, NULL, NULL );
while( nMaxNodeCount*4 < nShapeCount )
{
psTree->nMaxDepth += 1;
nMaxNodeCount = nMaxNodeCount * 2;
}
}
/* -------------------------------------------------------------------- */
/* Allocate the root node. */
/* -------------------------------------------------------------------- */
psTree->psRoot = SHPTreeNodeCreate( padfBoundsMin, padfBoundsMax );
/* -------------------------------------------------------------------- */
/* Assign the bounds to the root node. If none are passed in, */
/* use the bounds of the provided file otherwise the create */
/* function will have already set the bounds. */
/* -------------------------------------------------------------------- */
if( padfBoundsMin == NULL )
{
SHPGetInfo( hSHP, NULL, NULL,
psTree->psRoot->adfBoundsMin,
psTree->psRoot->adfBoundsMax );
}
/* -------------------------------------------------------------------- */
/* If we have a file, insert all it's shapes into the tree. */
/* -------------------------------------------------------------------- */
if( hSHP != NULL )
{
int iShape, nShapeCount;
SHPGetInfo( hSHP, &nShapeCount, NULL, NULL, NULL );
for( iShape = 0; iShape < nShapeCount; iShape++ )
{
SHPObject *psShape;
psShape = SHPReadObject( hSHP, iShape );
SHPTreeAddShapeId( psTree, psShape );
SHPDestroyObject( psShape );
}
}
return psTree;
}
SHPCreateTree( SHPHandle hSHP, int nDimension, int nMaxDepth,
double *padfBoundsMin, double *padfBoundsMax )
{
SHPTree *psTree;
if( padfBoundsMin == NULL && hSHP == NULL )
return NULL;
/* -------------------------------------------------------------------- */
/* Allocate the tree object */
/* -------------------------------------------------------------------- */
psTree = (SHPTree *) malloc(sizeof(SHPTree));
if( NULL == psTree )
{
return NULL;
}
psTree->hSHP = hSHP;
psTree->nMaxDepth = nMaxDepth;
psTree->nDimension = nDimension;
psTree->nTotalCount = 0;
/* -------------------------------------------------------------------- */
/* If no max depth was defined, try to select a reasonable one */
/* that implies approximately 8 shapes per node. */
/* -------------------------------------------------------------------- */
if( psTree->nMaxDepth == 0 && hSHP != NULL )
{
int nMaxNodeCount = 1;
int nShapeCount;
SHPGetInfo( hSHP, &nShapeCount, NULL, NULL, NULL );
while( nMaxNodeCount*4 < nShapeCount )
{
psTree->nMaxDepth += 1;
nMaxNodeCount = nMaxNodeCount * 2;
}
#ifdef USE_CPL
CPLDebug( "Shape",
"Estimated spatial index tree depth: %d",
psTree->nMaxDepth );
#endif
/* NOTE: Due to problems with memory allocation for deep trees,
* automatically estimated depth is limited up to 12 levels.
* See Ticket #1594 for detailed discussion.
*/
if( psTree->nMaxDepth > MAX_DEFAULT_TREE_DEPTH )
{
psTree->nMaxDepth = MAX_DEFAULT_TREE_DEPTH;
#ifdef USE_CPL
CPLDebug( "Shape",
"Falling back to max number of allowed index tree levels (%d).",
MAX_DEFAULT_TREE_DEPTH );
#endif
}
}
/* -------------------------------------------------------------------- */
/* Allocate the root node. */
/* -------------------------------------------------------------------- */
psTree->psRoot = SHPTreeNodeCreate( padfBoundsMin, padfBoundsMax );
if( NULL == psTree->psRoot )
{
return NULL;
}
/* -------------------------------------------------------------------- */
/* Assign the bounds to the root node. If none are passed in, */
/* use the bounds of the provided file otherwise the create */
/* function will have already set the bounds. */
/* -------------------------------------------------------------------- */
assert( NULL != psTree );
assert( NULL != psTree->psRoot );
if( padfBoundsMin == NULL )
{
SHPGetInfo( hSHP, NULL, NULL,
psTree->psRoot->adfBoundsMin,
psTree->psRoot->adfBoundsMax );
}
/* -------------------------------------------------------------------- */
/* If we have a file, insert all it's shapes into the tree. */
/* -------------------------------------------------------------------- */
if( hSHP != NULL )
{
int iShape, nShapeCount;
SHPGetInfo( hSHP, &nShapeCount, NULL, NULL, NULL );
for( iShape = 0; iShape < nShapeCount; iShape++ )
{
SHPObject *psShape;
psShape = SHPReadObject( hSHP, iShape );
if( psShape != NULL )
{
SHPTreeAddShapeId( psTree, psShape );
SHPDestroyObject( psShape );
}
}
}
return psTree;
}
