Graphics Options and Device Parameters Dictionary

POLYGONCLIP

Specifies the type of clipping used when two polygons overlap.

Used in:	GOPTIONS statement
Default:	device-dependent
Restriction:	not supported by Java or ActiveX
See also:	PCLIP

Syntax
Details

Syntax

POLYGONCLIP | NOPOLYGONCLIP

POLYGONCLIP: specifies polygon clipping, which enables a clipped polygon to be filled with a hardware pattern. POLYGONCLIP affects only graphs that have blanking areas or intersecting polygons.
NOPOLYGONCLIP: specifies line clipping; a polygon that has been line-clipped cannot use a hardware pattern.

Details

Clipping is the process of removing part of one polygon when two polygons intersect. For example, in a block map, a block might overlap the boundary of its map area. In this case, the polygon that makes up the map area is clipped so that you do not see the boundary line behind the block. (See Intersecting Polygons for an illustration of a clipped polygon.) The type of clipping used by a graph affects whether a clipped area can use hardware patterns.

POLYGONCLIP is affected by the PCLIP graphics option:

POLYGONCLIP with PCLIP or NOPCLIP: all areas can use hardware patterns
NOPOLYGONCLIP with NOPCLIP: all areas use only software patterns
NOPOLYGONCLIP with PCLIP: areas can use either hardware or software patterns depending on the nature of the clipped polygons.

Under some conditions the polygons might not be clipped correctly. Specifying both POLYGONCLIP and NOPCLIP will produce the correct graph.

Top of Page