pango-Bidirectional-Text {RGtk2} | R Documentation

## Bidirectional Text

### Description

Types and functions to help with handling bidirectional text

### Methods and Functions

`pangoUnicharDirection(ch)`
`pangoFindBaseDir(text, length = -1)`
`pangoGetMirrorChar(ch)`
`pangoBidiTypeForUnichar(ch)`

### Detailed Description

Pango supports bidirectional text (like Arabic and Hebrew) automatically. Some applications however, need some help to correctly handle bidirectional text.

The `PangoDirection` type can be used with `pangoContextSetBaseDir` to instruct Pango about direction of text, though in most cases Pango detects that correctly and automatically. The rest of the facilities in this section are used internally by Pango already, and are provided to help applications that need more direct control over bidirectional setting of text.

### Enums and Flags

`PangoDirection`

  The `PangoDirection` type represents a direction in the Unicode bidirectional algorithm; not every value in this enumeration makes sense for every usage of `PangoDirection`; for example, the return value of `pangoUnicharDirection` and `pangoFindBaseDir` cannot be `PANGO_DIRECTION_WEAK_LTR` or `PANGO_DIRECTION_WEAK_RTL`, since every character is either neutral or has a strong direction; on the other hand `PANGO_DIRECTION_NEUTRAL` doesn't make sense to pass to `pangoItemizeWithBaseDir`.

  The `PANGO_DIRECTION_TTB_LTR`, `PANGO_DIRECTION_TTB_RTL` values come from an earlier interpretation of this enumeration as the writing direction of a block of text and are no longer used; See `PangoGravity` for how vertical text is handled in Pango.

  `ltr`

    A strong left-to-right direction

  `rtl`

    A strong right-to-left direction

  `ttb-ltr`

    Deprecated value; treated the same as `PANGO_DIRECTION_RTL`.

  `ttb-rtl`

    Deprecated value; treated the same as `PANGO_DIRECTION_LTR`

`PangoBidiType`

  The `PangoBidiType` type represents the bidirectional character type of a Unicode character as specified by the Unicode bidirectional algorithm (http://www.unicode.org/reports/tr9/). Since 1.22

  `l`

    Left-to-Right

  `lre`

    Left-to-Right Embedding

  `lro`

    Left-to-Right Override

  `r`

    Right-to-Left

  `al`

    Right-to-Left Arabic

  `rle`

    Right-to-Left Embedding

  `rlo`

    Right-to-Left Override

  `pdf`

    Pop Directional Format

  `en`

    European Number

  `es`

    European Number Separator

  `et`

    European Number Terminator

  `an`

    Arabic Number

  `cs`

    Common Number Separator

  `nsm`

    Nonspacing Mark

  `bn`

    Boundary Neutral

  `b`

    Paragraph Separator

  `s`

    Segment Separator

  `ws`

    Whitespace

  `on`

    Other Neutrals

### Author(s)

Derived by RGtkGen from GTK+ documentation

### References

https://docs.gtk.org/Pango/

[Package RGtk2 version 2.20.40 Index]