github.com/cybriq/giocore@v0.0.7-0.20210703034601-cfb9cb5f3900/font/gofont/gofont.go (about)

     1  // SPDX-License-Identifier: Unlicense OR MIT
     2  
     3  // Package gofont exports the Go fonts as a text.Collection.
     4  //
     5  // See https://blog.golang.org/go-fonts for a description of the
     6  // fonts, and the golang.org/x/image/font/gofont packages for the
     7  // font data.
     8  package gofont
     9  
    10  import (
    11  	"fmt"
    12  	"sync"
    13  
    14  	"golang.org/x/image/font/gofont/gobold"
    15  	"golang.org/x/image/font/gofont/gobolditalic"
    16  	"golang.org/x/image/font/gofont/goitalic"
    17  	"golang.org/x/image/font/gofont/gomedium"
    18  	"golang.org/x/image/font/gofont/gomediumitalic"
    19  	"golang.org/x/image/font/gofont/gomono"
    20  	"golang.org/x/image/font/gofont/gomonobold"
    21  	"golang.org/x/image/font/gofont/gomonobolditalic"
    22  	"golang.org/x/image/font/gofont/gomonoitalic"
    23  	"golang.org/x/image/font/gofont/goregular"
    24  	"golang.org/x/image/font/gofont/gosmallcaps"
    25  	"golang.org/x/image/font/gofont/gosmallcapsitalic"
    26  
    27  	"github.com/cybriq/giocore/font/opentype"
    28  	"github.com/cybriq/giocore/text"
    29  )
    30  
    31  var (
    32  	once       sync.Once
    33  	collection []text.FontFace
    34  )
    35  
    36  func Collection() []text.FontFace {
    37  	once.Do(func() {
    38  		register(text.Font{}, goregular.TTF)
    39  		register(text.Font{Style: text.Italic}, goitalic.TTF)
    40  		register(text.Font{Weight: text.Bold}, gobold.TTF)
    41  		register(text.Font{Style: text.Italic, Weight: text.Bold}, gobolditalic.TTF)
    42  		register(text.Font{Weight: text.Medium}, gomedium.TTF)
    43  		register(text.Font{Weight: text.Medium, Style: text.Italic}, gomediumitalic.TTF)
    44  		register(text.Font{Variant: "Mono"}, gomono.TTF)
    45  		register(text.Font{Variant: "Mono", Weight: text.Bold}, gomonobold.TTF)
    46  		register(text.Font{Variant: "Mono", Weight: text.Bold, Style: text.Italic}, gomonobolditalic.TTF)
    47  		register(text.Font{Variant: "Mono", Style: text.Italic}, gomonoitalic.TTF)
    48  		register(text.Font{Variant: "Smallcaps"}, gosmallcaps.TTF)
    49  		register(text.Font{Variant: "Smallcaps", Style: text.Italic}, gosmallcapsitalic.TTF)
    50  		// Ensure that any outside appends will not reuse the backing store.
    51  		n := len(collection)
    52  		collection = collection[:n:n]
    53  	})
    54  	return collection
    55  }
    56  
    57  func register(fnt text.Font, ttf []byte) {
    58  	face, err := opentype.Parse(ttf)
    59  	if err != nil {
    60  		panic(fmt.Errorf("failed to parse font: %v", err))
    61  	}
    62  	fnt.Typeface = "Go"
    63  	collection = append(collection, text.FontFace{Font: fnt, Face: face})
    64  }