Represents the "GlyphOrientationVertical" entry of the standard layout attributes object.

It is an optional entry defined as part of the PDF 1.5 specification.

It contains a string representing a PDF name object.

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

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

• angle
• Auto
• or

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 343, page 597.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 378, page 770.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 344, page 600.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 379, page 774.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 345, page 604.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 380, page 778.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 346, page 608.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 381, page 782.

The GlyphOrientationVertical entry controls glyph orientation in vertical writing mode. Auto applies standard rules per character type. A value of 90 rotates all glyphs 90 degrees clockwise.