Represents the "Binding" entry of the richmediaparams dictionary object.

It is an optional entry defined as part of the PDF 1.7 Extension Level 3 specification.

It contains a string representing a PDF name object.

The PDF specification states that this item assumes a value of "None" if no value has been provided.

This item may take one of the following valid values:.

• None
• Foreground
• Background
• Material

For definitive details see:.

Adobe Supplement to the ISO 32000, BaseVersion: 1.7, ExtensionLevel: 3; Table: 9.51c, page 90.

The binding name selects the 3D binding mode for the instance: None, Background, Material, or Base, controlling how the media content is rendered in relation to the 3D scene's geometry.