Determines if a percentage polygon overlap has occurred and, if so, returns the polygon and the percentage overlap with the input polygon.
Syntax
intl gdlFindPolygonOverlapPercentage( gdlFileHandle hFile, gdlShape polygon, gdlShape* output, double* overlap );
Arguments
hFile
The gdlFileHandle returned by gdlOpenSpatialFile. Input.
polygon
The polygon with which to determine overlap. Input.
output
A pointer to the overlapping polygon. Output.
overlap
The percentage of overlap. Output.
Return values
GDL_WRONG_TYPE
GDL_NOT_FOUND
GDL_ERROR
GDL_OK
Prerequisites
gdlOpenSpatialFile
Alternates
gdlFindPolygonOverlap
Notes
Following instances of this function, you should call gdlShapeFree with the output polygon when you are finished using the output polygon to release system resources.
The percentage overlap determines the confidence rating.
The following diagram illustrates a polygon and the percentage overlap with the input polygon:
