XeLaTeX interpration of LaTeX for localization

tools/tex-to-svg.js

@@ -0,0 +1,134 @@
+/**
+ *
+ *  This script acts as support to the latex-loader for webpack.
+ *  The latex-loader finds and preprocesses LaTeX elements,
+ *  and then this script is run via execSync, to get the SVG
+ *  conversion happening synchronously, since Webpack doesn't
+ *  do async loaders (unfortunately).
+ *
+ */
+var fs = require("fs-extra");
+var path = require("path");
+var cleanUp = require("./cleanup");
+var execSync = require("child_process").execSync;
+
+// Get the LaTeX we need, either straight up or base64 encoded:
+var latex = process.argv.indexOf("--latex");
+
+if (latex === -1) {
+  var base64 = process.argv.indexOf("--base64");
+  if (base64 === -1) {
+    console.error("missing [--latex] or [--base64] runtime option");
+    process.exit(1);
+  }
+  base64 = process.argv[base64+1];
+  latex = new Buffer(base64, "base64").toString();
+} else {
+  // get the --latex value
+  var args = Array.from(process.argv);
+  latex = args.slice(latex+1).join(" ");
+  if(!latex) {
+    console.error("missing [--latex] runtime option string");
+    process.exit(1);
+  }
+}
+
+// Get the filename we'll need to write:
+var hash = process.argv.indexOf("--hash");
+hash = (latex === -1) ? Date.now() : process.argv[hash+1];
+var dir = path.resolve(__dirname + "/../images/latex");
+fs.ensureDirSync(dir);
+var filename = path.join(dir, hash + ".svg");
+
+// also set up a tex source copy
+dir = path.join(dir, "source");
+fs.ensureDirSync(dir);
+var TeXfilename = path.join(dir, hash + ".tex");
+
+var latexSourceCode = cleanUp(latex);
+var aligned = latexSourceCode.indexOf("\\begin{aligned}") !== -1;
+
+//if (aligned) {
+  latexSourceCode = [
+    '\\[',
+    latexSourceCode,
+    '\\]'
+  ].join('\n');
+//}
+
+// Convert the passed LaTeX to SVG form
+// write the .tex source
+var filedata = [
+  '\\documentclass[12pt]{article}',
+  '\\usepackage[paperwidth=12in, paperheight=12in]{geometry}', // pdfcrop will remove the unused bits later
+  '\\pagestyle{empty}',
+  '\\usepackage{color}',
+  '\\usepackage{amsmath}',
+  '\\usepackage{unicode-math}'
+]
+
+if (process.env.locale === 'zh-CN') {
+  filedata = filedata.concat([
+    '\\usepackage{xeCJK}',
+    '\\xeCJKsetup{CJKmath=true}',
+    '\\setCJKmainfont{SimSun}'
+  ]);
+}
+
+if (process.env.locale === 'ja-JP') {
+  filedata = filedata.concat([
+    '\\usepackage{xeCJK}',
+    '\\xeCJKsetup{CJKmath=true}',
+    '\\setCJKmainfont{MS Mincho}'
+  ]);
+}
+
+filedata = filedata.concat([
+  '\\setmainfont[Ligatures=TeX]{TeX Gyre Pagella}',
+  '\\setmathfont{TeX Gyre Pagella Math}',
+
+  // '\\setmainfont{XITS}',
+  // '\\setmathfont{XITS Math}',
+
+  // '\\setmainfont[Ligatures=TeX]{Cambria}',
+  // '\\setmathfont{Cambria Math}',
+
+  // '\\setmainfont[Ligatures=TeX]{LucidaBrightOT}',
+  // '\\setmathfont{LucidaBrightMathOT}',
+
+  '\\begin{document}',
+  latexSourceCode,
+  '\\end{document}'
+]);
+
+filedata = filedata.join('\n');
+fs.writeFileSync(TeXfilename, filedata);
+
+var PDFfilename = TeXfilename.replace(".tex",".pdf");
+var PDFfilenameCropped = TeXfilename.replace(".tex","-crop.pdf");
+var SVGfilename = TeXfilename.replace(".tex",".svg");
+
+// make the SVGfilename one dir higher
+SVGfilename = path.resolve(path.join(path.dirname(TeXfilename), '..', hash + ".svg"));
+
+// run xelatex on this file
+try {
+  var cmd = `npm run xelatex -- -output-directory "${path.dirname(TeXfilename)}" "${TeXfilename}"`;
+  console.log(cmd);
+  console.log(" - running xelatex on " + hash + ".tex");
+  execSync(cmd); //, { stdio: 'inherit' });
+
+  var cmd = `npm run pdfcrop -- "${ PDFfilename }"`;
+  console.log(" - cropping PDF to document content");
+  execSync(cmd); //, { stdio: 'inherit' });
+
+  var cmd = `pdf2svg "${ PDFfilenameCropped }" "${ SVGfilename }"`;
+  console.log(" - converting cropped PDF to SVG");
+  execSync(cmd); //, { stdio: 'inherit' });
+
+  var cmd = `npm run svgo -- "${ SVGfilename }"`;
+  console.log(" - cleaning up SVG");
+  execSync(cmd); //, { stdio: 'inherit' });
+}
+
+catch (e) { console.error(e); process.exit(1); }