NGUI is available in three different licenses:

Now that we know the different licenses, let's make a quick comparison between NGUI and Unity's default UI system.

With Unity's GUI, you must create the entire UI in code by adding lines that display labels, textures, or any other UI element on the screen. These lines have to be written inside a special function called every frame: OnGUI().This is no longer necessary—with NGUI, UI elements are simple GameObjects!

You can create widgets—this is what NGUI calls labels, sprites, input fields, and so on—move them, rotate them, and change their dimensions using handles or the Inspector. Copy, paste, create prefabs, and every other useful feature of Unity's workflow are available.

These widgets are viewed by a camera and rendered on a layer you can specify. Most of the parameters are accessible through Unity's Inspector, and you can see what your UI looks like directly in the game window, without having to hit Unity's play button.

Sprites and fonts are all contained in a large texture called atlas. With only a few clicks, you can easily create and edit your atlases. If you don't have any images to create your own UI assets, simple default atlases come with the plugin.

Using this system ensures that, for a complex UI window composed of different textures and fonts, the same material and texture will be used when rendering.

This results in only one draw call for the entire window. That, along with other optimizations, makes NGUI the perfect tool for working on mobile platforms.

There also is an easy-to-use event framework written in C#. The plugin comes with a large number of additional components you can attach to any GameObject. These components can perform advanced tasks depending on which events are triggered: hover, click, input, and so on. Therefore, you might enhance your UI experience while keeping it simple to configure. Code less, get more.

NGUI comes with its own localization system, enabling you to easily set up and change your UI's language with the push of a button. All your strings are located in a.txt file.

Lighting, normal mapping, and refraction shaders are supported, which can give you beautiful results. Clipping is also a shader-controlled feature with NGUI, used for showing or hiding specific areas of your UI.

We've now covered what NGUI's main features are; let's see what we'll create using this book.