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.