A collection of Unity 3D tools has been combined to become the Unity 3D GameKit. In this recipe, we'll create a new Scene and make use of some of the kit's Prefabs and Scripts to illustrate how characters can interact with objects such as doors and pickups. In this recipe, we'll explore how we can add interactivity, such as a character walking onto a pressure pad that opens a door. We'll also learn how to declare that an item should be collectable, and so when the player walks into it, they can add a crystal to their inventory. Note that if your system cannot handle the gigabytes of rich assets for the main 3D Game Kit, then we have added steps in the There's more... section for working with the 3D Game Kit Lite that Unity released:
Figure 7.1 – The interactable door Scene we'll create with the 3D Game Kit
