Represents the "Decode" entry of the type 4 shading dictionary object.

It is a required entry defined as part of the PDF 1.0 specification.

It contains an array which contains doubles, representing PDF numeric objects.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 82, page 189.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 81, page 237.

The Decode array maps the encoded integer coordinate and component values to the working ranges used during rendering. It contains 2 × (number of coordinates per vertex + number of components per vertex) values, arranged as min/max pairs.

The first two pairs map the x and y coordinate integers; subsequent pairs map each color component. Linear interpolation between the min and max converts an integer to its floating-point value.