font_example_test.go

Documentation: gonum.org/v1/plot/vg/vgsvg

     1  // Copyright ©2021 The Gonum Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package vgsvg_test
     6  
     7  import (
     8  	"log"
     9  	"os"
    10  
    11  	lmit "github.com/go-fonts/latin-modern/lmroman10italic"
    12  	lreg "github.com/go-fonts/liberation/liberationserifregular"
    13  	xfnt "golang.org/x/image/font"
    14  	"golang.org/x/image/font/opentype"
    15  
    16  	"gonum.org/v1/plot"
    17  	"gonum.org/v1/plot/font"
    18  	"gonum.org/v1/plot/plotter"
    19  	"gonum.org/v1/plot/vg"
    20  	"gonum.org/v1/plot/vg/draw"
    21  	"gonum.org/v1/plot/vg/vgsvg"
    22  )
    23  
    24  func Example_embedFonts() {
    25  	// Use Latin-Modern fonts.
    26  	cmi10 := font.Font{Typeface: "Latin-Modern", Style: xfnt.StyleItalic}
    27  	fnt, err := opentype.Parse(lmit.TTF)
    28  	if err != nil {
    29  		log.Fatalf("could not parse Latin-Modern fonts: %+v", err)
    30  	}
    31  
    32  	font.DefaultCache.Add([]font.Face{{
    33  		Font: cmi10,
    34  		Face: fnt,
    35  	}})
    36  	plot.DefaultFont = cmi10
    37  
    38  	p := plot.New()
    39  	p.Title.Text = "Scatter plot"
    40  	p.X.Label.Text = "x-Axis"
    41  	p.Y.Label.Text = "y-Axis"
    42  
    43  	scatter, err := plotter.NewScatter(plotter.XYs{{X: 1, Y: 1}, {X: 0, Y: 1}, {X: 0, Y: 0}})
    44  	if err != nil {
    45  		log.Fatalf("could not create scatter: %v", err)
    46  	}
    47  	p.Add(scatter)
    48  
    49  	c := vgsvg.NewWith(
    50  		vgsvg.UseWH(5*vg.Centimeter, 5*vg.Centimeter),
    51  		vgsvg.EmbedFonts(true),
    52  	)
    53  	p.Draw(draw.New(c))
    54  
    55  	f, err := os.Create("testdata/embed_fonts.svg")
    56  	if err != nil {
    57  		log.Fatalf("could not create output SVG file: %+v", err)
    58  	}
    59  	defer f.Close()
    60  
    61  	_, err = c.WriteTo(f)
    62  	if err != nil {
    63  		log.Fatalf("could not write output SVG plot: %+v", err)
    64  	}
    65  
    66  	err = f.Close()
    67  	if err != nil {
    68  		log.Fatalf("could not close output SVG file: %v", err)
    69  	}
    70  }
    71  
    72  func Example_standardFonts() {
    73  	// Use standard fonts.
    74  	tms := font.Font{Typeface: "Times"}
    75  	fnt, err := opentype.Parse(lreg.TTF)
    76  	if err != nil {
    77  		log.Fatalf("could not parse Times fonts: %+v", err)
    78  	}
    79  
    80  	font.DefaultCache.Add([]font.Face{{
    81  		Font: tms,
    82  		Face: fnt,
    83  	}})
    84  	plot.DefaultFont = tms
    85  
    86  	p := plot.New()
    87  	p.Title.Text = "Scatter plot"
    88  	p.X.Label.Text = "x-Axis"
    89  	p.Y.Label.Text = "y-Axis"
    90  
    91  	scatter, err := plotter.NewScatter(plotter.XYs{{X: 1, Y: 1}, {X: 0, Y: 1}, {X: 0, Y: 0}})
    92  	if err != nil {
    93  		log.Fatalf("could not create scatter: %v", err)
    94  	}
    95  	p.Add(scatter)
    96  
    97  	err = p.Save(5*vg.Centimeter, 5*vg.Centimeter, "testdata/standard_fonts.svg")
    98  	if err != nil {
    99  		log.Fatalf("could not save SVG plot: %+v", err)
   100  	}
   101  }
   102
View as plain text