It seems that the description of value "tbRl" is wrong

Correct description to be: "Specifies that text in the parent object shall flow from top to bottom vertically, then right to left horizontally on the page."

"ST_TextDirection (Text Flow Direction)"
, page 1829. Section 2.18.100

ed

Proposed Disposition of DIS 29500 Comment IL-0020 (Modified: 2008-01-02) Agreed; in Part 4, §2.18.100, page 1,830, the description of the tbRl enumeration value will be changed as follows: tbRl (Top to Bottom, Right to Left) Specifies that text in the parent object shall flow from right to left horizontally, then top to bottom vertically on the page vertically on the page, then right to left horizontally on the page, as if the text were rotated 90 degrees . This means that horizontal vertical lines are filled before the text expands vertically horizontally .