montage

Generate CSS sprite sheets and the corresponding stylesheet

Getting Started

This plugin requires Grunt 0.4 or later and depends upon the montage command line tool bundled with ImageMagick. If you don't already have it (and you're running on *nix/Mac OS), it will be automatically installed.

If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:

npm install grunt-montage --save-dev

Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:

grunt.loadNpmTasks("grunt-montage");

The "montage" task

Overview

In your project's Gruntfile, add a section named montage to the data object passed into grunt.initConfig().

grunt.initConfig({
    montage: {
        targetName: {
            // Target-specific montage configuration
        }
    }
});

Options

options.size

Type: Number Default value: 16

The width/height of each image included in the sprite sheet.

options.prefix

Type: String Default value: ".montage"

A CSS selector to prefix all sprite classes with.

options.outputImage

Type: String Default value: "montage.png"

The name of the generated sprite sheet image.

options.outputStylesheet

Type: String Default value: "montage.css"

The name of the generated stylesheet.

options.baseRules

Type: Object Default value: undefined

A map of CSS properties/values that will be appended to the base rule in the stylesheet.

options.magick

Type: Object Default value: undefined

A map of command-line options for the ImageMagick montage tool.

Usage Examples

Default Options

In this example, the default options are used to do generate a sprite sheet from 16x16 pixel versions of all the .png files in the images/icons directory. The sprite sheet will be created at assets/sprites/montage.css and the image at assets/sprites/montage.png, based on the default option values listed above.

grunt.initConfig({
    montage: {
        simple: {
            files: {
                "assets/sprites": [
                    "images/icons/*.png"
                ]
            }
        }
    }
});

Custom Options

In this example, custom options are used to configure the output. It will generate a sprite sheet of 32x32 pixel images at assets/sprites/sprites.png and the corresponding stylesheet at assets/sprites/styles.css.

grunt.initConfig({
    montage: {
        simple: {
            files: {
                "assets/sprites": [
                    "images/icons/*.png"
                ]
            },
            options: {
                size: 32,
                outputImage: "sprites.png",
                outputStylesheet: "styles.css"
            }
        }
    }
});

In this example, custom options are used to pass extra configuration through to ImageMagick. It will generate the same sprite sheet as the previous example, but with a transparent background.

grunt.initConfig({
    montage: {
        simple: {
            files: {
                "assets/sprites": [
                    "images/icons/*.png"
                ]
            },
            options: {
                size: 32,
                outputImage: "sprites.png",
                outputStylesheet: "styles.css",
                magick: {
                    background: "none"
                }
            }
        }
    }
});

In this example, custom options are used to add to the base CSS rule in the generated stylesheet. It will add display and text-indent properties to the base rule.

grunt.initConfig({
    montage: {
        simple: {
            files: {
                "assets/sprites": [
                    "images/icons/*.png"
                ]
            },
            options: {
                baseRules: {
                    display: "inline-block",
                    "text-indent": "-9999px"
                }
            }
        }
    }
});

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 and test your code using Grunt.

Licensing and Attribution

Grunt Montage is released under the MIT license as detailed in the LICENSE file that should be distributed with this library; the source code is freely available.

Grunt Montage was developed by James Allardice during work on White Label Dating, while employed by Global Personals Ltd. Global Personals Ltd have kindly agreed to the extraction and release of this software under the license terms above.