svg から png を生成するようにした

go.mod

@@ -12,6 +12,8 @@ require (
 	github.com/minio/selfupdate v0.6.0
 	github.com/mitchellh/cli v1.1.5
 	github.com/pelletier/go-toml/v2 v2.1.0
+	github.com/srwiley/oksvg v0.0.0-20221011165216-be6e8873101c
+	github.com/srwiley/rasterx v0.0.0-20220730225603-2ab79fcdd4ef
 	github.com/yuin/goldmark v1.5.6
 	github.com/yuin/goldmark-highlighting/v2 v2.0.0-20230729083705-37449abec8cc
 )
@@ -40,6 +42,8 @@ require (
 	github.com/spf13/cast v1.5.1 // indirect
 	golang.org/x/crypto v0.17.0 // indirect
 	golang.org/x/image v0.15.0 // indirect
+	golang.org/x/net v0.10.0 // indirect
 	golang.org/x/sys v0.15.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

go.sum

@@ -105,6 +105,10 @@ github.com/shopspring/decimal v1.3.1/go.mod h1:DKyhrW/HYNuLGql+MJL6WCR6knT2jwCFR
 github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
 github.com/spf13/cast v1.5.1 h1:R+kOtfhWQE6TVQzY+4D7wJLBgkdVasCEFxSUBYBYIlA=
 github.com/spf13/cast v1.5.1/go.mod h1:b9PdjNptOpzXr7Rq1q9gJML/2cdGQAo69NKzQ10KN48=
+github.com/srwiley/oksvg v0.0.0-20221011165216-be6e8873101c h1:km8GpoQut05eY3GiYWEedbTT0qnSxrCjsVbb7yKY1KE=
+github.com/srwiley/oksvg v0.0.0-20221011165216-be6e8873101c/go.mod h1:cNQ3dwVJtS5Hmnjxy6AgTPd0Inb3pW05ftPSX7NZO7Q=
+github.com/srwiley/rasterx v0.0.0-20220730225603-2ab79fcdd4ef h1:Ch6Q+AZUxDBCVqdkI8FSpFyZDtCVBc2VmejdNrm5rRQ=
+github.com/srwiley/rasterx v0.0.0-20220730225603-2ab79fcdd4ef/go.mod h1:nXTWP6+gD5+LUJ8krVhhoeHjvHTutPxMYl5SvkcnJNE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
@@ -141,6 +145,8 @@ golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v
 golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
 golang.org/x/net v0.2.0/go.mod h1:KqCZLdyyvdV855qA2rE3GC2aiw5xGR5TEjj8smXukLY=
+golang.org/x/net v0.10.0 h1:X2//UzNDwYmtCLn7To6G58Wr6f5ahEAQgKNzv9Y951M=
+golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -166,6 +172,8 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=

internal/build/frontmatter.go

@@ -8,10 +8,11 @@ import (
 	"net/http"
 	"unicode/utf8"
 
-	"golang.org/x/image/draw"
+	"github.com/srwiley/oksvg"
+	"github.com/srwiley/rasterx"
 )
 
-const emojiPngSize = 72
+const emojiPngSize = 400
 
 type YamlFrontMatter struct {
 	Author      string   `yaml:"author"`
@@ -41,30 +42,22 @@ func (y *YamlFrontMatter) saveTwemojiImage(w io.Writer, ext string) error {
 	if ext != ".svg" && ext != "png" {
 		return fmt.Errorf("unsupported file extension: %s", ext)
 	}
-	var url string
-	if ext == "svg" {
-		url = fmt.Sprintf("https://jdecked.github.io/twemoji/v/latest/svg/%s.svg", codepoint)
-	} else if ext == "png" {
-		url = fmt.Sprintf("https://jdecked.github.io/twemoji/v/latest/72x72/%s.png", codepoint)
-	}
 
-	res, err := http.Get(url)
+	res, err := http.Get(fmt.Sprintf("https://jdecked.github.io/twemoji/v/latest/svg/%s.svg", codepoint))
 	if err != nil {
 		return err
 	}
 	if res.StatusCode != http.StatusOK {
 		return fmt.Errorf("failed to download emoji: %s", res.Status)
 	}
 
-	// png の場合はリサイズする
+	// png の場合 svg から変換する
 	if ext == "png" {
-		img, err := png.Decode(res.Body)
-		if err != nil {
-			return err
-		}
-		newImage := image.NewRGBA(image.Rect(0, 0, emojiPngSize*2, emojiPngSize*2))
-		draw.BiLinear.Scale(newImage, newImage.Bounds(), img, img.Bounds(), draw.Over, nil)
-		return png.Encode(w, newImage)
+		icon, _ := oksvg.ReadIconStream(res.Body)
+		icon.SetTarget(0, 0, float64(emojiPngSize), float64(emojiPngSize))
+		rgba := image.NewRGBA(image.Rect(0, 0, emojiPngSize, emojiPngSize))
+		icon.Draw(rasterx.NewDasher(emojiPngSize, emojiPngSize, rasterx.NewScannerGV(emojiPngSize, emojiPngSize, rgba, rgba.Bounds())), 1)
+		return png.Encode(w, rgba)
 	} else {
 		_, err = io.Copy(w, res.Body)
 		return err