2022-11-27 09:17:29AM

d2renderers/d2latex/latex.go

@@ -0,0 +1,43 @@
+package d2latex
+
+import (
+	_ "embed"
+	"fmt"
+
+	v8 "rogchap.com/v8go"
+)
+
+//go:embed polyfills.js
+var polyfillsJS string
+
+//go:embed setup.js
+var setupJS string
+
+//go:embed mathjax.js
+var mathjaxJS string
+
+func SVG(s string) (string, error) {
+	v8ctx := v8.NewContext()
+
+	if _, err := v8ctx.RunScript(polyfillsJS, "polyfills.js"); err != nil {
+		return "", err
+	}
+
+	if _, err := v8ctx.RunScript(mathjaxJS, "mathjax.js"); err != nil {
+		return "", err
+	}
+
+	if _, err := v8ctx.RunScript(setupJS, "setup.js"); err != nil {
+		return "", err
+	}
+
+	val, err := v8ctx.RunScript(fmt.Sprintf(`adaptor.innerHTML(html.convert("%s", {
+  em: 16,
+  ex: 8,
+}))`, s), "value.js")
+	if err != nil {
+		return "", err
+	}
+
+	return val.String(), nil
+}

d2renderers/d2latex/latex_test.go

@@ -0,0 +1,17 @@
+package d2latex
+
+import (
+	"encoding/xml"
+	"testing"
+)
+
+func TestSVG(t *testing.T) {
+	svg, err := SVG("$$a + b = c$$")
+	if err != nil {
+		t.Fatal(err)
+	}
+	var xmlParsed interface{}
+	if err := xml.Unmarshal([]byte(svg), &xmlParsed); err != nil {
+		t.Fatalf("invalid SVG: %v", err)
+	}
+}

d2renderers/d2latex/setup.js

@@ -0,0 +1,6 @@
+const adaptor = MathJax._.adaptors.liteAdaptor.liteAdaptor();
+MathJax._.handlers.html_ts.RegisterHTMLHandler(adaptor)
+const html = MathJax._.mathjax.mathjax.document('', {
+  InputJax: new MathJax._.input.tex_ts.TeX(),
+  OutputJax: new MathJax._.output.svg_ts.SVG({ fontCache: "none" }),
+});