Represents the "EA" entry of the 3d background 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.

The PDF specification states that this item assumes a value of false if no value has been provided.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 306, page 527.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 317, page 659.

The EA entry, when true, uses the background as an environment map for reflections and ambient lighting in the 3D scene. This makes the background visible in reflective model surfaces.