7 Putting a GUI onto a game
This chapter covers
- Comparing old and newer GUI systems
- Creating a canvas for the interface
- Positioning UI elements using anchor points
- Adding interactivity to the UI (buttons, sliders, and so on)
- Broadcasting and listening for events from the UI
In this chapter, you’ll build a 2D interface display for a 3D game. So far, we’ve focused on the virtual scene itself while building a first-person demo. But every game needs abstract interaction and information displays in addition to the virtual scene the gameplay takes place in. This is true for all games, whether they’re 2D or 3D, first-person shooters or puzzle games. So, while the techniques in this chapter will be used on a 3D game, they apply to 2D games as well.
These abstract interaction displays are referred to as the UI, or more specifically, the GUI. GUI refers to the visual part of the interface, such as text and buttons (see figure 7.1). Technically, the UI includes non-graphical controls, such as the keyboard or gamepad, but people tend to be referring to the graphical parts when they say “user interface.”
Figure 7.1 The GUI (a heads-up display, or HUD) you’ll create for a game
