Represents the "ST" entry of the 3d cross section dictionary object.

It is an optional entry defined as part of the PDF 2.0 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: 311, page 532.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 322, page 665.

The ST entry, when true, caps the cut surfaces by rendering solid material at the cut face. Without capping, the cross-section reveals a hollow shell; with capping, the cut appears as a solid material with a visible cross-sectional face.