Finds first polygon overlapping the input polygon and calculates the percentage of the input polygon overlapped by the polygon in the object file.
Syntax
01 SPHANDLE PIC S9(9) BINARY.
01 POINTS OCURRS 8 TIMES.
15 PNTS PIC S9(9) BINARY.
01 NUMPOINTSPERPOLYPIC S9(9) BINARY.
01 NUMPOLYGONS PIC S9(9) BINARY.
01 NAMEBUFFER X(80).
01 BUFSIZE X(80).
01 NUMINCREMENTS PIC S9(9) BINARY.
01 PERCENTAGE COMP-2.
01 SPRETCODE PIC S9(9) BINARY.
*
CALL ‘SPOFFPX'
USING SPHANDLE, POINTS, NUMPOINTPERPOLY, NUMPOLYGONS, NAMEBUFFER, BUFSIZE, NUMINCREMENTS, PERCENTAGE, SPRETCODE.
Arguments
SPHANDLE File handle from SPOFOP. Input.
PNTS Input polygon; an array of x,y point values. Input. NUMPOINTSPERPOLY Array of point counts for each polygon in the region.
Input.
NUMPOLYGONS Number of polygons in region to search. Input.
NAMEBUFFER A buffer to be filled with the identifier of the object from the object file which the input polygon overlaps. Output.
BUFSIZE The size of the buffer that contains the identifier of the object which the input region overlaps. If the buffer size is smaller than the identifier, the identifier is truncated. Input.
NUMINCREMENTS Number of increments used in the overlap percentage calculation. Input.
PERCENTAGE Calculated overlap percentage. Output.
Return Values
PIP-ERROR
PIP-NOT-FOUND
PIP-REGION-OVERLAP PIP-INPUT-IN-OBJECT PIP-OBJECT-IN-INPUT
PIP-OBJECT-EQUALS-INPUT
SPOFOP.
Prerequisites
Alternates
SPFFPG, SPCKROX.
Notes
This procedure compares an input polygon with polygons in an existing object file. If any region in the object file intersects with the input region, the intersection type is returned. If no overlapping region is found, the procedure returns PIP-NOT-FOUND.
If the number of increments is greater than 0 and the percentage is not NULL, this procedure computes the percentage of the input region overlapped by the region in the spatial file. The accuracy and precision of the calculation increases as the number of increments is increased. Note that increasing the number of increments also increases processing time.