How code is structured. For questions on the internal design of a game engine.

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122
votes
1answer
25k views

What is the role of “systems” in a component-based entity architecture?

I've been reading a lot about entity components and systems and have thought that the idea of an entity just being an ID is quite interesting. However I don't know how this completely works with the ...
106
votes
3answers
47k views

Tips for writing the main game loop? [closed]

Can anyone recommend some good tips, articles, sites, etc. for writing the main game loop? What are some things that you should do in the game loop, and what are some things that you shouldn't do in ...
48
votes
10answers
14k views

Game State 'Stack'?

I was thinking about how to implement game states into my game. The main things I want for it are: Semi-transparent top states-being able to see through a pause menu to the game behind Something OO-...
141
votes
8answers
34k views

Why are MVC & TDD not employed more in game architecture? [closed]

I will preface this by saying I haven't looked a huge amount of game source, nor built much in the way of games. But coming from trying to employ 'enterprise' coding practices in web apps, looking at ...
69
votes
11answers
13k views

How to design a replay system

So how would I design a replay system? You may know it from certain games like Warcraft 3 or Starcraft where you can watch the game again after it has been played already. You end up with a ...
102
votes
9answers
14k views

Entity communication: Message queue vs Publish/Subscribe vs Signal/Slots

How do game engine entities communicate? Two use cases: How would entity_A send a take-damage message to entity_B? How would entity_A query entity_B's HP? Here's what I've encountered so far: ...
34
votes
3answers
6k views

Several classes need to access the same data, where should the data be declared?

I have a basic 2D tower defense game in C++. Each map is a separate class which inherits from GameState. The map delegates the logic and drawing code to each object in the game and sets data such as ...
47
votes
7answers
5k views

How can I set up a flexible framework for handling achievements?

Specifically, what is the best way to implement an achievement system flexible enough to handle going beyond simple statistics-driven achievements such as "kill x enemies." I'm looking for something ...
15
votes
2answers
8k views

Implementing a camera / viewport to a 2D game

What is the most practical way to implement camera/viewport to a 2D-game? I've read, that I should store the object world position instead of position relative to the screen? Current situation: I ...
98
votes
11answers
24k views

Good resources for learning about game architecture? [closed]

Are there any good resources for learning about game architectures? I am looking for high level overviews of different architectures. I tend to find information about the various pieces of a game such ...
18
votes
6answers
12k views

How do I build a 2D physics engine? [closed]

The most advanced games I've made are a 8-ball pool game made with the physics engine Box2dFlashAS3 and a platform game with levels. When I did platform games, I've always wished to know how to make ...
15
votes
2answers
3k views

Where should collision detection logic be placed?

I am developing a small 2D game engine. The characters have a paint method which currently does the following: Calculate the new position of the character as per its speed, etc. Update the collision ...
6
votes
3answers
7k views

Synchronizing clients with a server and with each other

What is the best way for keeping all clients synchronized with a server and with each other? Currently, we have two approaches in mind: When a client sends something to the server, the server ...
22
votes
6answers
7k views

What designs are there for a component based entity system that are user friendly but still flexible?

I've been interested in the component based entity system for a while, and read countless articles on it (The Insomiac games, the pretty standard Evolve Your Hierarchy, the T-Machine, Chronoclast ... ...
17
votes
2answers
4k views

How are physics or graphics components typically built in a component-oriented system?

I have spent the last 48 hours reading up on Object Component systems, and feel I am ready enough to start implementing it. I got the base Object and Component classes created, but now that I need to ...
17
votes
3answers
5k views

Game engine and data driven design

I've heard about data driven design and have been researching about it for a while. So, I've read several articles to get the concepts. One of the article is Data Driven Design written by Kyle ...
8
votes
2answers
6k views

Interaction between engine parts

I want to ask a question about how the information exchange between game engine parts should be implemented. The engine is separated in four parts: logic, data, UI, graphics. In the beginning I made ...
16
votes
4answers
2k views

Calculating the output of two armies fighting

I am programming a strategic game using Flash. The game works very similar to the famous game "Travian". My problem is as follows: I am trying to make the calculation of the troops lost as a result ...
15
votes
2answers
5k views

Inheritance vs Composition

I make my money in C# Generally in that language I like to decouple everything to the high heavens using interfaces. This has served me well in enterprise code but in writing games in C# I find myself ...
12
votes
5answers
4k views

How to properly handle collision in a component-based game?

Trying to wrap my head around the ways to properly handle collision in a game designed around components. I see many examples have some sort of PhysicsComponent that gets added to the entity's list ...
1
vote
3answers
2k views

Game state sharing data

A game is a set of Game States. Each Game State contains game objects, may be list, may be scene graph or any other data structure. We can use Game States as Game Locations, too. How do you share ...
5
votes
6answers
3k views

Making classes available to others

I'm currently working on a 2D game engine in XNA, and I am very interested in architecture, and how best to let my game objects communicate. I know a lot of people use a Singleton design but I ...
4
votes
1answer
356 views

LWJGL Eclipse Resource Deployment

I'm still experimenting with some OpenGL in LWJGL, and as I get to know more and more about OpenGL, I start to do more complicated things like multi texturing, shadowmapping and more. Now, right now I'...
5
votes
3answers
624 views

Is a custom coordinate system possible in Unity

Is it possible to create a custom coordinate system (i.e the one using double for coordinates or the one dividing the world into 'chunks' of safe size) not constrained by the floating point precision ...
51
votes
8answers
17k views

Event-driven Communication in a Game Engine: Yes or No?

I am reading Game Coding Complete and the author recommends Event Driven communication among game objects and modules. Basically, all living game actors should communicate with the key modules (...
14
votes
6answers
5k views

Game Components, Game Managers and Object Properties

I'm trying to get my head around component based entity design. My first step was to create various components that could be added to an object. For every component type i had a manager, which would ...
27
votes
5answers
2k views

Doing powerups in a component-based system

I'm just starting really getting my head around component based design. I don't know what the "right" way to do this is. Here's the scenario. The player can equip a shield. The the shield is drawn ...
12
votes
5answers
6k views

Keyboard input system handling

Note: I have to poll, rather than do callbacks because of API limitations (SFML). I also apologize for the lack of a 'decent' title. I think I have two questions here; how to register the input I'm ...
17
votes
1answer
3k views

How should I structure an extensible asset loading system?

For a hobby game engine in Java, I want to code a simple but flexible asset/resource manager. Assets are sounds, images, animation, models, textures, et cetera. After a few hours of browsing and some ...
20
votes
2answers
3k views

Component-Based System online resources

I've been considering moving to a more component-based approach in my games. Does anyone else have any decent reference material or sample implementations that would help make this transition a little ...
23
votes
4answers
2k views

Appropriate level of granularity for component-based architecture

I'm working on a game with a component-based architecture. An Entity owns a set of Component instances, each of which has a set of Slot instances with which to store, send, and receive values. Factory ...
6
votes
2answers
7k views

Use a SQL Database for a Desktop Game

Developing a Game Engine I am planning a computer game and its engine. There will be a 3 dimensional world with first person view and it will be single player for now. The programming language is C++ ...
3
votes
1answer
403 views

How should my game characters store their abilities/spells?

I'm new to game development and a bit confused about how to effectively store an object's access to certain spells/abilities. The player and mob objects are all generated from the same class. However,...
39
votes
7answers
27k views

Where can I find good (well organized) examples of game code? [closed]

Where can I find good (well organized) examples of game code? I'm hoping that I can pick up some organizational tips. Most examples in books are too short and leave out lots of detail for the sake of ...
22
votes
4answers
2k views

Architecture a for a central renderer rather than self-rendering [duplicate]

For the architectural side of rendering, there's two main ways: having each object render itself, and having a single renderer which renders everything. I'm currently aiming for the second idea, for ...
41
votes
5answers
6k views

How to avoid the GameManager god object?

I just read an answer to a question about structuring game code. It made me wonder about the ubiquitous GameManager class, and how it often becomes an issue in a production environment. Let me ...
32
votes
7answers
2k views

Elegant way to simulate large amounts of entities within a game world

Assume you have a game in which there are many (many many) entities serving some functions, not all of which are constantly needed or need to be considered in every frame. The concrete problem I am ...
29
votes
10answers
5k views

Alternative to Game State System?

As far as I can tell, most games have some sort of "game state system" which switches between the different game states; these might be things like "Intro", "MainMenu", "CharacterSelect", "Loading", ...
21
votes
4answers
4k views

“The Game Object” - and component-based design

I've been working on some hobby projects the last 3-4 years. Just simple 2d and 3d games. But lately I have started a bigger project. Soo in the last couple of months I've been trying to design a game ...
20
votes
4answers
6k views

How to design an AssetManager?

What is the best approach to designing an AssestManager that will hold references to graphics, sounds, etc. of a game? Should these assets be stored in a key/value Map pair? I.e. I ask for "...
18
votes
4answers
8k views

Resource Managers - Are they any good?

I've seen many a time in source code, things like this [well, this is more of a pseudo C++ idea of mine] typedef shared_ptr<Resource> ResourcePtr;// for ease ResourcePtr sound1 = ...
19
votes
4answers
5k views

How to implement behavior in a component-based game architecture?

I am starting to implement player and enemy AI in a game, but I am confused about how to best implement this in a component-based game architecture. Say I have a following player character that can ...
15
votes
4answers
4k views

Alternatives to Singletons / globals

I've heard countless times about the pitfalls of Singletons / globals, and I understand why they're so often frowned upon. What I don't understand is what the elegant, non-messy alternative is. It ...
14
votes
1answer
7k views

How to apply Data Oriented Design with Object Oriented Programming? [closed]

I've read lots of articles about Data Oriented Design (DOD) and I understand it but I can't design an Object Oriented Programming (OOP) system with DOD in mind, I think my OOP education is blocking me....
13
votes
4answers
10k views

Why has the industry switched from C to C++?

First of all i would like to have a real answer, i'm always trying to get more from various sources and articles, and when I read things like C++ is slow because it has virtual functions and because ...
16
votes
3answers
2k views

Dynamic Memory Allocation and Memory Management

In an average game, there are hundreds or maybe thousands of objects in the scene. Is it completely correct to allocate memory for all objects, including gun shots (bullets), dynamically via default ...
13
votes
4answers
3k views

How can I design an effective game object interaction scheme with a component-based architecture?

This is a design question... I'm sure this could be generalized more, but I'm having a hard time with it. I am wondering about design for game object interactions - here is my example (2D puzzle-...
9
votes
3answers
3k views

Component-based design: handling objects interaction

I'm not sure how exactly objects do things to other objects in a component based design. Say I have an Obj class. I do: Obj obj; obj.add(new Position()); obj.add(new Physics()); How could I then ...
6
votes
4answers
3k views

Retrieving components from game objects (entities)

Using C# and XNA 4, I've made the decision to go for an entity-component based design for my game after reading such posts as this and this, but I'm now struggling to find how to retrieve components ...
11
votes
3answers
893 views

How do I make complex AI manageable? [closed]

In the past, I've used simple systems like finite state machines (FSMs) and hierarchical FSMs to control AI behavior. This pattern falls apart very quickly or any complex system. I've heard about ...