The Design Process
You will recall from Chapter 2, "Design Components and Processes," that the game design process takes place in three stages: concept, elaboration, and tuning. Designing the user interface takes place early during the elaboration stage. There's no point in designing it any earlier; if you do so before the end of the concept phase, the overall design may change dramatically and your early UI work will be wasted.
This section outlines the steps of the UI design process. You can find definitions for many of the components you will use for your game's UI later in this chapter.
A gameplay mode consists of a camera model, an interaction model, and the game - play (challenges and actions) available. During the concept stage, define, in general
terms, what gameplay modes the game will have. At the beginning of the elaboration stage, start to design the gameplay modes in detail.
Your first job will be to design the primary gameplay mode, the one in which the player spends the majority of her time. See the sections "Interaction Models" and "Camera Models" later in this chapter for details about each of them. Once you have chosen the camera model, interaction model, and gameplay for the primary gameplay mode, you can begin to create the details of the user interface for that mode.
When you have designed the primary gameplay mode, move on to the other modes that you think your game will need. Plan the structure of the game using a flow - board, as described in Chapter 2. In addition to gameplay activities, don't forget story-related activities. Design modes that deliver narrative content and engage in dialog if your game supports these. Be sure to include a way to interrupt narrative and get back to gameplay, and a pause menu (if it's a real-time game) so the player can answer the telephone.
Gameplay modes do not typically use completely different user interfaces but share a number of UI features, so it's best to define all the modes before you begin UI work. If your game provides a small number of gameplay modes (say, five or fewer), you can start work on the user interfaces as soon as you decide what purpose each mode serves and what the player will do there. However, if the game provides a large number of modes, then you should wait until after you have planned the structure of the game and you understand how the game moves from mode to mode.
Once you have the list of gameplay modes, start to think about what visual elements and controls each will need. Using graph paper or a diagramming tool such as Microsoft Visio, make a flowchart of the progression of menus, dialog boxes, and other user interface elements that you intend to use in each mode. Also document what the input devices will do in each.
Occasionally gameplay modes can share a single UI when the modes differ only in the challenges they offer. If you want to allow the player to control the change from one mode to another, your user interface must offer commands to accomplish these mode changes.
Steps in designing a game's user interface include, for each mode, designing a screen layout, selecting the visual elements that will tell the player what she needs to know, and defining the inputs to make the game do what she wants to do. We'll take up these topics in turn. The remainder of this discussion assumes that you're working on the user interface for the most important mode—the primary gameplay mode—although this advice applies equally to any mode.