rpgcraft

RPGCraft - Minecraft / Terraria / RPGMaker mashup

Setup

• Install Visual Studio 2017 from https://visualstudio.microsoft.com/downloads/
  • Make sure to install C# and C++ support.
  • Note: Visual Studio 2019 hasn't been tested but will probably work.
• Install Unity 2018.3.7f1 from https://unity3d.com/get-unity/download/archive
  • Install the platforms that you want to test on.
  • Only PC has been tested.

Run the Game

• Open the Scene Assets/Scenes/main.unity.
• Click Play.

Test the Main Screen

• Open the Scene Assets/Scenes/title.unity
• Click Play

Test the UI

• Open the Scene Assets/Scene/ui.unity

Architecture

• All singletons are Unity objects and are named __ in the Scene.
  • They are marked as DontDestroyOnLoad and thus survive between scenes reload.
• All Unity classes are overloaded:
  • MonoBehaviorEx replaces MonoBehavior
• Scripts/Engine is for general purpose code.
• Scripts/Game is for game specific code.
• JSON.Net (Newtonsoft) is used for JSON to C# Structure serialization and vice-versa.
  • Found many quirks with built-in Unity JSON parsing.
  • JSON.Net is well supported.
  • JSON.Net provides auto-serialization, making serialization code trivial to write.
  • https://www.newtonsoft.com/json

World Generation

• World is generated with Chunk. Each Chunk represents a 64x64 tiles and is a single Unity Object.
• Game Coordinate starts from (0,0). Each tile measure 1x1 in game coordinate.
• At initial world generation, the chunk where the player is is generated. Neighborhood chunks are also generated. -- This prevents the player from seeing empty space.
• The world will generate different type of chunks according to the game rules, such as how much of a certain types of terrain to create, and how coupled this terrain will be.
• Generating chunks is expensive, and a noticeable hitch is felt whenever a new chunk is generated.

Rendering

• Each Tile is drawn using 2 triangles, 6 vertices. Each Chunk thus has 24,576 vertices.
• At run-time, an atlas is generated from the tiles in tilesInfo.json.
• The triangle tesselation for each chunk is done at run-time.

Entity / Collision

• Every game object in the game is a Entity and is tracked by the EntityManager. -- For example, Player is an Entity. Slime is a Enemy which is a type of `Entity..
• The Unity collision system is not used to track collision. -- This is because it is a physics based system, which was overkill.
• The CollisionManager takes care of associating each Entity with a Chunk. This is an optimization for collision to prevent checking for collision between entities that can't touch each other.
• Collisions detection is dynamic, it should be impossible for an object to tunnel through another object without colliding. -- OnTouch will be called on your entity if it has collided. You can use this to perform action such as picking up item, or sending damage events. -- Two collided objects will be replaced so that they don't collide. This is done through a recalage algorithm that pushes back objects.
• Some of the collision code handling the main player is in GameManager.
• The game will side-step the player if colliding on the side, to allow for better navigation, similar to Zelda 1.
• Animation code is custom and is done through the EntityRender class -- EntityRender: Contains a list of animation (by names) and a sequence of frames for the animation. -- Enemies expect the following animations: Left, Right, Up and Down.

UI

• The UIManager lives in a different scene UI. -- This was done so that we could change the main scene while still keeping the UI alive.
• The UIManager handles the UI overlay of the game. It expects to find certain assets by name.
• The DynamicText feature is an API that allows you to display text on the screen.

Managers

GameManager

• Responsible for the state of the game. Drives everything else.

AudioManager

• Contains the music and SFX asset references.
• Contains API to Play and Stop audio.

CollisionManager

• APIs for detecting collision

DebugManager

• General debugging functionalities.

DataManager

• Loads all game data, this includes:
  • enemiesInfo.json: Loots, what enemies give when they are killed.
  • tilesInfo.json: Describe tiles (texture, transformation, properties such as speed, passable, etc.)
• Game data are all in json format
• No custom editor for json data (yet).

EntityManager

• All Entities register themselves with the EntityManager

Entity

• Never call Unity built-in Destroy on an Entity, use RequestDestroy instead. -- This makes it so that the Entity is properly removed from the EntityManager and collision system. It also makes it so that the entity is never dangling within a game frame. It is only when the frame is over that the entities are cleaned up.

InputManager

• Handle mouse and keyboard input

ItemManager

RandomManager

• Provides generic helpers to generate random numbers.
• Currently only a single instance is used, but later on there should be different instance to allow deterministic simulation.

SpawnManager

• Spawn enemies on the screen according to game rules.
• Is responsible for creating the Unity object when spawning.

TimeManager

• Contains information about the current time, last frame time, etc.

Inventory System

• Everything you can pickup in the game is defined in ETile.
• Items are defined in tilesInfo and must match the enum value. Improvement -- Ideally this class would be self-generated OR; -- The inventory system should use string only and we get rid of ETile completely.