R: Type 1 and CID Fonts

Type1Font {grDevices} | R Documentation

## Type 1 and CID Fonts

### Description

These functions are used to define the translation of a R graphics font family name to a Type 1 or CID font descriptions, used by both the `postscript` and `pdf` graphics devices.

### Usage

    Type1Font(family, metrics, encoding = "default")

    CIDFont(family, cmap, cmapEncoding, pdfresource = "")

### Arguments

`family` | a character string giving the name to be used internally for a Type 1 or CID-keyed font family. This needs to uniquely identify each family, so if you modify a family which is in use (see `postscriptFonts`) you need to change the family name.
`metrics` | a character vector of four or five strings giving paths to the afm (Adobe Font Metric) files for the font.
`cmap` | the name of a CMap file for a CID-keyed font.
`encoding` | for `Type1Font`, the name of an encoding file. Defaults to `"default"`, which maps on this platform to "ISOLatin1.enc". Otherwise, a file name in the ‘enc’ directory of the grDevices package, which is used if the path does not contain a path separator. An extension `".enc"` can be omitted.
`cmapEncoding` | The name of a character encoding to be used with the named CMap file: strings will be translated to this encoding when written to the file.
`pdfresource` | A chunk of PDF code; only required for using a CID-keyed font on `pdf`; users should not be expected to provide this.

### Details

For `Type1Fonts`, if four ‘.afm’ files are supplied the fifth is taken to be `"Symbol.afm"`. Relative paths are taken relative to the directory ‘R_HOME/library/grDevices/afm’. The fifth (symbol) font must be in `AdobeSym` encoding. However, the glyphs in the first four fonts are referenced by name and any encoding given within the ‘.afm’ files is not used.

Glyphs in CID-keyed fonts are accessed by ID (number) and not by name. The CMap file maps encoded strings (usually in a MBCS) to IDs, so `cmap` and `cmapEncoding` specifications must match. There are no real bold or italic versions of CID fonts (bold/italic were very rarely used in traditional CJK topography), and for the `pdf` device all four font faces will be identical. However, for the `postscript` device, bold and italic (and bold italic) are emulated.

CID-keyed fonts are intended only for use for the glyphs of CJK languages, which are all monospaced and are all treated as filling the same bounding box. (Thus `plotmath` will work with such characters, but the spacing will be less carefully controlled than with Western glyphs.) The CID-keyed fonts do contain other characters, including a Latin alphabet: non-CJK glyphs are regarded as monospaced with half the width of CJK glyphs. This is often the case, but sometimes Latin glyphs designed for proportional spacing are used (and may look odd). We strongly recommend that CID-keyed fonts are only used for CJK glyphs.

### Value

A list of class `"Type1Font"` or `"CIDFont"`.

### See Also

`postscript`, `pdf`, `postscriptFonts`, and `pdfFonts`.

### Examples

    ## This duplicates "ComputerModernItalic".
    CMitalic <- Type1Font("ComputerModern2",
                          c("CM_regular_10.afm", "CM_boldx_10.afm",
                            "cmti10.afm", "cmbxti10.afm",
                            "CM_symbol_10.afm"),
                          encoding = "TeXtext.enc")

    ## Not run:
    ## This could be used by
    postscript(family = CMitalic)
    ## or
    postscriptFonts(CMitalic = CMitalic)  # once in a session
    postscript(family = "CMitalic", encoding = "TeXtext.enc")
    ## End(Not run)

[Package grDevices version 2.8.1 Index]