Font metrics parser

Javascript tool for parsing font metrics data. Each font is loaded via CSS Font Loading API and then parsed from canvas in Chromium browser with experimentalCanvasFeatures set to true

Usage

• install package

npm install font-metrics --save-dev

• include parser via import

import 'fontParser' from 'font-metrics'

or require syntax

var fontParser = require('font-metrics')

• call parse method

fontParser(options).parse();

Options

• fonts {Object[]} Array of objects.
• fonts.fontFamily {String} font-family
• [fonts.src] {String} Custom fonts are expected to have src value specified. Each font will be loaded via CSS Font Loading API and then parsed.
• debug {Boolean} Show logs.
• output {String} Output path.
• filename {String} Output filename.
• fontSize {Number} Font size
• [express] {Object} Express options
  • [express.port] {Number} Express port
  • [express.mount] {Object[]} Additional directories that could be mounted to Express server. Usefull for parsing font files saved locally.
  • [express.mount.alias] {String} Local path alias
  • [express.mount.path] {String} Local path that could be used for using static files
• nightmare {Object} Nightmare options. Accepts any options that are valid for Nightmare initialization.
  • show {Boolean} Show browser window. Default: false

Returns

JSON data

Usage example

var fontMetrics = require('font-metrics');

fontMetrics({
	fonts: [
		{
			fontFamily: 'Arial'
		},
		{
			fontFamily: 'Roboto',
			src: 'https://fonts.gstatic.com/s/roboto/v15/sTdaA6j0Psb920Vjv-mrzH-_kf6ByYO6CLYdB4HQE-Y.woff2'
		},
		{
			fontFamily: 'SteelworksVintageDemo',
			src: 'mounted-path/SteelworksVintageDemo.otf'
		}
	],
	output: './metrics/',
	filename: 'metrics.json',
	express: {
		port: 3412,
		mount: [
			{
				alias: 'mounted-path',
				path: __dirname + '/your-local-dir-with-fonts'
			}
		]
	}
}).parse();

Output example

{
	"metrics": {
		"Arial": {
			"_fontSize": 24,
			"_textBaseline": "alphabetic",
			"actualBoundingBoxAscent": 0,
			"actualBoundingBoxDescent": 24,
			"actualBoundingBoxLeft": 0,
			"actualBoundingBoxRight": 93,
			"alphabeticBaseline": 0,
			"emHeightAscent": 0,
			"emHeightDescent": 0,
			"fontBoundingBoxAscent": 22,
			"fontBoundingBoxDescent": 5,
			"hangingBaseline": -17.600000381469727,
			"ideographicBaseline": 5,
			"width": 93.375
		},
		"Roboto": {
			"_fontSize": 24,
			"_textBaseline": "alphabetic",
			"actualBoundingBoxAscent": 0,
			"actualBoundingBoxDescent": 24,
			"actualBoundingBoxLeft": 0,
			"actualBoundingBoxRight": 85,
			"alphabeticBaseline": 0,
			"emHeightAscent": 0,
			"emHeightDescent": 0,
			"fontBoundingBoxAscent": 22,
			"fontBoundingBoxDescent": 6,
			"hangingBaseline": -17.600000381469727,
			"ideographicBaseline": 6,
			"width": 85.30078125
		},
		"SteelworksVintageDemo": {
			"_fontSize": 24,
			"_textBaseline": "alphabetic",
			"actualBoundingBoxAscent": 0,
			"actualBoundingBoxDescent": 24,
			"actualBoundingBoxLeft": 0,
			"actualBoundingBoxRight": 69,
			"alphabeticBaseline": 0,
			"emHeightAscent": 0,
			"emHeightDescent": 0,
			"fontBoundingBoxAscent": 19,
			"fontBoundingBoxDescent": 7,
			"hangingBaseline": -15.199999809265137,
			"ideographicBaseline": 7,
			"width": 68.9759521484375
		}
	},
	"src": [
		{
			"fontFamily": "Arial"
		},
		{
			"fontFamily": "Roboto",
			"src": "https://fonts.gstatic.com/s/roboto/v15/sTdaA6j0Psb920Vjv-mrzH-_kf6ByYO6CLYdB4HQE-Y.woff2"
		},
		{
			"fontFamily": "SteelworksVintageDemo",
			"src": "mounted-path/SteelworksVintageDemo.otf"
		}
	]
}