github.com/Kintar/etxt@v0.0.0-20221224033739-2fc69f000137/examples/gtxt/font_library/main.go (about)

     1  package main
     2  
     3  import "os"
     4  import "path/filepath"
     5  import "log"
     6  import "fmt"
     7  
     8  import "github.com/Kintar/etxt"
     9  
    10  // Must be compiled with '-tags gtxt'.
    11  // This example expects a path to a font directory as the first
    12  // argument, reads the fonts in it and prints their names to the
    13  // terminal.
    14  
    15  func main() {
    16  	// get font directory path
    17  	if len(os.Args) != 2 {
    18  		msg := "Usage: expects one argument with the path to the font directory\n"
    19  		fmt.Fprint(os.Stderr, msg)
    20  		os.Exit(1)
    21  	}
    22  
    23  	// print given font directory
    24  	fontDir, err := filepath.Abs(os.Args[1])
    25  	if err != nil {
    26  		log.Fatal(err)
    27  	}
    28  	fmt.Printf("Reading font directory: %s\n", fontDir)
    29  
    30  	// create font library
    31  	fontLib := etxt.NewFontLibrary()
    32  	added, skipped, err := fontLib.ParseDirFonts(fontDir)
    33  	if err != nil {
    34  		log.Fatalf("Added %d fonts, skipped %d, failed with '%s'", added, skipped, err.Error())
    35  	}
    36  	fmt.Printf("Added %d fonts, skipped %d\n", added, skipped)
    37  
    38  	// print, for each font parsed, its name, family and subfamily
    39  	err = fontLib.EachFont(
    40  		func(fontName string, font *etxt.Font) error {
    41  			family, err := etxt.FontFamily(font)
    42  			if err != nil {
    43  				log.Printf("(failed to load family for font %s: %s)", fontName, err.Error())
    44  				family = "unknown"
    45  			}
    46  			subfamily, err := etxt.FontSubfamily(font)
    47  			if err != nil {
    48  				log.Printf("(failed to load subfamily for font %s: %s)", fontName, err.Error())
    49  				subfamily = "unknown"
    50  			}
    51  			fmt.Printf("* %s (%s | %s)\n", fontName, family, subfamily)
    52  			return nil
    53  		})
    54  	if err != nil {
    55  		log.Fatal("FontLibrary.EachFont error!: " + err.Error())
    56  	}
    57  	fmt.Print("Program exited successfully.\n")
    58  }