Introduction

This document outlines the state machine and the states used to control the flow of Zooshi, which are located in the states directory.

State Machine

Zooshi uses a state machine to control the flow between its various states, including the menus, the game itself, and the in-game editor. Each state is in control of the game when active, implementing an AdvanceFrame call to advance the state every frame, and a Render call in order to render the state to screen. In order to change states, changes are made to the next_state variable, passed in during AdvanceFrame. Shared functions needed by the states, such as rendering the world, and updating the camera, are provided in states_common.cpp.

Loading State

The initial state used while the game assets are being loaded. Note that the assets are not queued by the state itself, but instead in game.cpp, InitializeAssets. After the loading is complete, which is handled by fplbase's AssetManager, the state transitions into the game menu state.

Game Menu State

This state is used to manage the menus between games, powered by FlatUI, which can be seen in gui.cpp. The menu manages the type of menu being displayed, and based on the input from FlatUI, transitions between them, the game, and exiting. This state also handles integration with Google Play Game Services.

Intro State

This state is used when entering Cardboard gameplay. By introducing a state between the menu and gameplay for Cardboard, it allows the user to place the device in Cardboard before the start of the game. It also allows the Cardboard SDK to be oriented based on the direction the player is facing when they leave the state, guaranteeing they will be facing in the correct direction on game start.

Gameplay State

This state is used to control the gameplay, updating and rendering the world appropriately, for all types of input controllers, including Cardboard. The state checks for the various state transitions that can occur from it, to the pause state, game over, or the in-game editor.

Pause State

This state is used for pausing from the gameplay state, with the menus again using FlatUI, to either transition back into the game, or to the menu state.

Gameover State

This state is used when the game has finished, from not feeding enough patrons in the previous lap. A brief cutscene plays, using the EndGameEvent on patrons, after which it can return to the menu state. Note that when playing in Cardboard, it instead restarts the gameplay state, as the menu does not support being viewed while in Cardboard.

Scene Lab State

This state handles the in-game editor, which is powered by Scene Lab, and can be entered by pressing F10 from the gameplay state. This state updates the Scene Lab, and upon exit returns back to the gameplay state, preserving the changes that where made to the game.