Language Direction
Language Direction
Joe's original proposal
|
Request Title |
New attributes: WritingModeInline and WritingModeBlock |
| Request Submitted By | PDF/UA |
| Executive Summary | Defines the direction of text (existing definition is deprecated) |
| Rationale | Required to enable semantically correct rendering of written language in PDF. Will be required by PDF/UA. |
| Use Case(s) | Specification of the direction of text. |
| Details of Proposed Change |
Modify Table 386 and add note as described below. |
Modifications to Table 386
| Key | Type | Value |
|---|---|---|
| WritingMode | name |
Add this copy to the end of the description for this value: Beginning with 32000-2, WritingMode is deprecated to WritingModeBlock and WritingModeInline. |
| WritingModeBlock | name |
(Optional; inheritable) The directions of layout progression for stacking of BLESs (block progression). WritingModeBlock specifies the block direction of text (typically the direction of lines over a page). The WritingModeBlock attribute shall be used with the WritingModeInline attribute. Specified layout directions apply to child elements of the attributed structure element. Values for rectilinear text:LR (left to right) Values for curved text:CW (ClockWise) Values for diagonal text:LLUR (lower left to upper right) Values for text lacking direction:None (no declared text direction) |
| WritingModeInline | name |
(Optional; inheritable) The directions of layout progression for packing of ILSEs (inline progression). WritingModeInline specifies the inline direction of text, that is, the direction of text within a block (typically the direction of characters within lines). The WritingModeInline attribute shall be used with the WritingModeBlock attribute. Specified layout directions apply to child elements of the attributed structure element. Values for WritingModeInline are identical to those for WritingModeBlock. |
Add a new Note following Table 386:
Implementing the WritingModeBlock and WritingModeInline attributes
The typical writing mode for Western writing systems:
WritingModeBlock: TB, WritingModeInline: LR
The typical writing mode for Arabic and Hebrew writing systems:
WritingModeBlock: TB, WritingModeInline: RL
The typical writing mode for Chinese and Japanese writing systems:
WritingModeBlock: RL, WritingModeInline: TB
The typical writing mode for a Mongolian writing system:
WritingModeBlock: LR, WritingModeInline: TB
Table rows (structure type TR) shall be stacked in the WritingModeBlock direction, cells within a row (structure type TD) in the WritingModeInline direction.
