phantomjssmith

PhantomJS engine for spritesmith.

Requirements

This depends on having phantomjs installed on your machine. This can be done globally as listed on the PhantomJS website or locally via the node module wrapper. This module has been tested against 1.9.2 and 1.9.8.

Global installation

PhantomJS installation instructions can be found on the PhantomJS website. When phantomjssmith is running, phantomjs must be resolvable via the PATH environment variable.

http://phantomjs.org/

Local installation

A phantomjs wrapper can be install via: npm install phantomjs

https://github.com/Medium/phantomjs

When running your phantomjssmith task, it must have node_modules/.bin/ in the PATH environment variable. The easiest way to accomplish this is by using npm scripts:

// Inside our `package.json`
{
  "scripts": {
    "build": "grunt sprite"
  }
}

# Runs `grunt sprite` with `node_modules/.bin/` appended to `PATH`
npm run build

Getting Started

Install the module with: npm install phantomjssmith

// Load in our dependencies
var Phantomjssmith = require('phantomjssmith');

// Create a new engine
var phantomjssmith = new Phantomjssmith();

// Interpret some images from disk
phantomjssmith.createImages(['img1.jpg', 'img2.png'], function handleImages (err, imgs) {
  // If there was an error, throw it
  if (err) {
    throw err;
  }

  // We recieve images in the same order they were given
  imgs[0].width; // 50 (pixels)
  imgs[0].height; // 100 (pixels)

  // Create a canvas that fits our images (200px wide, 300px tall)
  var canvas = phantomjssmith.createCanvas(200, 300);

  // Add the images to our canvas (at x=0, y=0 and x=50, y=100 respectively)
  canvas.addImage(imgs[0], 0, 0);
  canvas.addImage(imgs[1], 50, 100);

  // Export canvas to image
  var resultStream = canvas['export']({format: 'png'});
  resultStream; // Readable stream outputting PNG image of the canvas
});

Documentation

This module was built to the specification for spritesmith engines.

Specification version: 2.0.0

https://github.com/twolfson/spritesmith-engine-spec/tree/2.0.0

engine.createImages(images, cb)

Our createImages methods supports the following types of images:

• image String - Filepath to image
• image Object - Vinyl object with null for image (uses provided filepath)

We accept but don't fully support the following types of images:

• image Object - Vinyl object with buffer for image (ignores contents, uses provided filepath)
• image Object - Vinyl object with stream for image (ignores contents, uses provided filepath)

canvas.export(options)

Our export method provides support for the following options:

• options Object
  • timeout Number - Milliseconds to wait until automatically terminating PhantomJS script
    • By default, this is 10000 (10 seconds).
  • format String - Output image format to callback with. Currently, png and jpeg are available.
  • quality Number - If you are outputting a jpeg, the quality can be specified from 0 to 100.

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint using npm run lint and test via npm test.

Donating

Support this project and others by twolfson via donations.

http://twolfson.com/support-me

License

Copyright (c) 2013 Todd Wolfson

Licensed under the MIT license.