pangoMacros {RGtk2} | R Documentation

## Pango Convenience Macros

### Description

These macros and constants help you layout text with Pango.

### Usage

    pangoAscent(x)
    pangoDescent(x)
    pangoLbearing(x)
    pangoRbearing(x)
    PANGO_SCALE
    pangoPixels(size)
    PANGO_SCALE_LARGE
    PANGO_SCALE_MEDIUM
    PANGO_SCALE_SMALL
    PANGO_SCALE_X_LARGE
    PANGO_SCALE_X_SMALL
    PANGO_SCALE_XX_LARGE
    PANGO_SCALE_XX_SMALL

### Arguments

`x` | A rectangle describing the glyph extents
`size` | A size on the Pango scale

.

### Details

When positioning text, it is beneficial to know the extents of the glyphs being drawn. The macros `pangoAscent`, `pangoDescent`, `pangoLbearing`, and `pangoRbearing` perform simple math on the given rectangle (representing the glyph extents) to determine the corresponding properties. The "ascent" and "descent" are how high the glyph extends above and below the baseline, respectively. The "lbearing" and "rbearing" describe the left-most and right-most extents of the glyph.

The rest are merely constants for scaling. `PANGO_SCALE` is the factor by which device units are scaled to Pango units. To return to device units, use the `pangoPixels`. The rest are pre-fab factors for scaling by different degrees.

### Value

The requested quantity in the units of the provided rectangle.

### Author(s)

Michael Lawrence

[Package RGtk2 version 2.20.40 Index]