font subset function

src/subsetFont.js

@@ -0,0 +1,29 @@
+
+import isNode from 'detect-node'
+import { Font } from 'fonteditor-core'
+import fs from 'fs'
+import fetch from './fetch'
+
+async function subsetFont (fontPath, glyphs, options = {}) {
+  let data
+  if (!isNode || !options.local) {
+    data = await fetch(fontPath, 'arraybuffer')
+  } else {
+    data = await new Promise((resolve, reject) => {
+      fs.readFile(fontPath, (err, data) => {
+        if (err) reject(err)
+        else resolve(data)
+      })
+    })
+  }
+  return Font.create(data, {
+    type: 'ttf',
+    subset: glyphs,
+    hinting: true
+  }).write({
+    type: 'ttf',
+    hinting: true
+  })
+}
+
+export default subsetFont