/************************************************************************/
/* SHPCreateTree() */
/************************************************************************/
public static SHPTree Create(SHPHandle hSHP, int nDimension, int nMaxDepth,
double[] padfBoundsMin, double[] padfBoundsMax)
{
SHPTree psTree;
if (padfBoundsMin == null && hSHP == null)
{
return(null);
}
/* -------------------------------------------------------------------- */
/* Allocate the tree object */
/* -------------------------------------------------------------------- */
psTree = new 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;
SHPT nShapeType;
hSHP.GetInfo(out nShapeCount, out nShapeType, null, null);
while (nMaxNodeCount * 4 < nShapeCount)
{
psTree.nMaxDepth += 1;
nMaxNodeCount = nMaxNodeCount * 2;
}
}
/* -------------------------------------------------------------------- */
/* Allocate the root node. */
/* -------------------------------------------------------------------- */
psTree.psRoot = NodeCreate(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)
{
int nShapeCount;
SHPT nShapeType;
hSHP.GetInfo(out nShapeCount, out nShapeType,
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;
SHPT nShapeType;
hSHP.GetInfo(out nShapeCount, out nShapeType, null, null);
for (iShape = 0; iShape < nShapeCount; iShape++)
{
SHPObject psShape;
psShape = hSHP.ReadObject(iShape);
psTree.AddShapeId(psShape);
psShape = null;
}
}
return(psTree);
}
