cairo-font-options: cairo_font_options_t
In RGtk2: R Bindings for Gtk 2.8.0 and Above

Description Methods and Functions Detailed Description Structures Convenient Construction Enums and Flags Author(s) References

How a font should be rendered

cairoFontOptionsCreate()
cairoFontOptionsCopy(original)
cairoFontOptionsStatus(options)
cairoFontOptionsMerge(options, other)
cairoFontOptionsEqual(options, other)
cairoFontOptionsSetAntialias(options, antialias)
cairoFontOptionsGetAntialias(options)
cairoFontOptionsSetSubpixelOrder(options, subpixel.order)
cairoFontOptionsGetSubpixelOrder(options)
cairoFontOptionsSetHintStyle(options, hint.style)
cairoFontOptionsGetHintStyle(options)
cairoFontOptionsSetHintMetrics(options, hint.metrics)
cairoFontOptionsGetHintMetrics(options)
cairoFontOptions()

The font options specify how fonts should be rendered. Most of the time the font options implied by a surface are just right and do not need any changes, but for pixel-based targets tweaking font options may result in superior output on a particular display.

CairoFontOptions

An opaque structure holding all options that are used when rendering fonts.

Individual features of a CairoFontOptions can be set or accessed using functions named cairo_font_options_set_feature_name and cairo_font_options_get_feature_name, like cairoFontOptionsSetAntialias and cairoFontOptionsGetAntialias.

New features may be added to a CairoFontOptions in the future. For this reason, cairoFontOptionsCopy, cairoFontOptionsEqual, cairoFontOptionsMerge, and cairoFontOptionsHash() should be used to copy, check for equality, merge, or compute a hash value of CairoFontOptions objects.

cairoFontOptions is the equivalent of cairoFontOptionsCreate.

CairoSubpixelOrder

The subpixel order specifies the order of color elements within each pixel on the display device when rendering with an antialiasing mode of CAIRO_ANTIALIAS_SUBPIXEL.

default: Use the default subpixel order for for the target device
rgb: Subpixel elements are arranged horizontally with red at the left
bgr: Subpixel elements are arranged horizontally with blue at the left
vrgb: Subpixel elements are arranged vertically with red at the top
vbgr: Subpixel elements are arranged vertically with blue at the top

CairoHintStyle

Specifies the type of hinting to do on font outlines. Hinting is the process of fitting outlines to the pixel grid in order to improve the appearance of the result. Since hinting outlines involves distorting them, it also reduces the faithfulness to the original outline shapes. Not all of the outline hinting styles are supported by all font backends.

New entries may be added in future versions.

default: Use the default hint style for font backend and target device
none: Do not hint outlines
slight: Hint outlines slightly to improve contrast while retaining good fidelity to the original shapes.
medium: Hint outlines with medium strength giving a compromise between fidelity to the original shapes and contrast
full: Hint outlines to maximize contrast

CairoHintMetrics

Specifies whether to hint font metrics; hinting font metrics means quantizing them so that they are integer values in device space. Doing this improves the consistency of letter and line spacing, however it also means that text will be laid out differently at different zoom factors.

default: Hint metrics in the default manner for the font backend and target device
off: Do not hint font metrics
on: Hint font metrics

Derived by RGtkGen from GTK+ documentation

https://www.cairographics.org/manual/cairo-cairo-font-options-t.html

RGtk2 documentation built on Oct. 14, 2021, 5:08 p.m.