Class

CGFont

A set of character glyphs and layout information for drawing text.

Declaration

class CGFont

Overview

A glyph can represent a single character (such as ‘b’), more than one character (such as the “fi” ligature), or a special character such as a space. Core Graphics retrieves the glyphs for the font from ATS (Apple Type Services) and paints the glyphs based on the relevant parameters of the current graphics state.

Core Graphics provides a limited, low-level interface for drawing text. For information on text-drawing functions, see CGContext. For full Unicode and text-layout support, use the services provided by TextKit).

Topics

Creating Font Objects

init?(CGDataProvider)

Creates a font object from data supplied from a data provider.

init?(CFString)

Creates a font object corresponding to the font specified by a PostScript or full name.

Examining Font Metadata

var fullName: CFString?

Returns the full name associated with a font object.

Examining Font Metrics

var ascent: Int32

Returns the ascent of a font.

var capHeight: Int32

Returns the cap height of a font.

var descent: Int32

Returns the descent of a font.

var fontBBox: CGRect

Returns the bounding box of a font.

var italicAngle: CGFloat

Returns the italic angle of a font.

var leading: Int32

Returns the leading of a font.

var stemV: CGFloat

Returns the thickness of the dominant vertical stems of glyphs in a font.

var unitsPerEm: Int32

Returns the number of glyph space units per em for the provided font.

var xHeight: Int32

Returns the x-height of a font.

Working with PostScript Fonts

var postScriptName: CFString?

Obtains the PostScript name of a font.

func canCreatePostScriptSubset(CGFontPostScriptFormat) -> Bool

Determines whether Core Graphics can create a subset of the font in PostScript format.

enum CGFontPostScriptFormat

Possible formats for a PostScript font subset.

Working with Font Tables

var tableTags: CFArray?

Returns an array of tags that correspond to the font tables for a font.

func table(for: UInt32) -> CFData?

Returns the font table that corresponds to the provided tag.

Font Table Index Values

Possible values for an index into a font table.

Working with Variations

func copy(withVariations: CFDictionary?) -> CGFont?

Creates a copy of a font using a variation specification dictionary.

var variations: CFDictionary?

Returns the variation specification dictionary for a font.

var variationAxes: CFArray?

Returns an array of the variation axis dictionaries for a font.

Font Variation Axis Keys

Keys used for a font variation axis dictionary.

Working with Glyphs

var numberOfGlyphs: Int

Returns the number of glyphs in a font.

func name(for: CGGlyph) -> CFString?

Returns the glyph name of the specified glyph in the specified font.

func getGlyphWithGlyphName(name: CFString) -> CGGlyph

Returns the glyph for the glyph name associated with the specified font object.

typealias CGGlyph

An index into the internal glyph table of a font.

let kCGGlyphMax: CGFontIndex

The maximum allowed value of a CGGlyph.

typealias CGFontIndex

An index into a font table.

let kCGFontIndexMax: CGFontIndex

The maximum allowed value of a CGFontIndex.

let kCGFontIndexInvalid: CGFontIndex

A value representing an invalid CGFontIndex.

Working with Core Foundation Types

class var typeID: CFTypeID

Returns the Core Foundation type identifier for Core Graphics fonts.

See Also

Colors and Fonts

class CGColor

A set of components that define a color, with a color space specifying how to interpret them.

class CGColorConversionInfo

An object that describes how to convert between color spaces for use by other system services.

class CGColorSpace

A profile that specifies how to interpret a color value for display.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

Learn more about using Apple's beta software