Represents the "OP" entry of the graphics state parameter dictionary object.

It is an optional entry defined as part of the PDF 1.0 specification.

It contains a bool representing a PDF boolean object.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 58, page 129.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 57, page 162.

The OP flag controls overprinting for stroking operations. When true, stroked marks do not erase underlying colorants; instead they are added on top. When false, the stroke first clears the underlying colorants in the mark's area.

Overprint behaviour is output-device-dependent. It primarily affects separations-based printing workflows where different inks are applied to the same area.