14
votes
What's the appropiate way to achieve composition in Godot?
I have gone from a monolith player controller, to an state machine, to a behavior tree, to something closer to what you describe.
My current character controller looks something like this in the scene ...
- 28k
10
votes
Accepted
A more data oriented design approach to Entity Component System game engine
What's an object?
What we call an object or an entity depending on the model is, fundamentally, made of two parts: data, and behaviour. Game objects have properties and do things.
Let's take a ...
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10
votes
Accepted
Dealing with more complex entities in an ECS architecture
Games typically approach this type of issue using a transformation hierarchy.
In this model, each entity can be treated as a "child" of a "parent" entity. The entity's local ...
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9
votes
Accepted
What should be an entity/component, and what shouldn't?
A lot of systems in a game that needs to be updated are things that are not rendered and don't need any input, they simply need a call to their update function every frame. They don't have any ...
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8
votes
Accepted
How do components access one another in a component based entity system
Components are just a collection of data and logic. How you store and relate them to the logical entity is where you gain or lose performance depending on the strategy you choose.
My example and ...
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7
votes
Should components in Entity Component System pattern have logic?
I was considering voting to close this question as opinion-based, but I think there are a couple of misunderstandings about Entity-Component Systems and Data-Oriented Design here that are worth ...
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6
votes
Accepted
What is a faster alternative to a GetComponent from a RaycastHit?
You could use a Dictionary. Store all Transforms as a key with reference to each Car.
In this example, we have a god Game class that holds references to all Cars. (just make sure your Script ...
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5
votes
Accepted
Appropriate Cache Friendly Associative Container For An Entity Component System
Do the simplest thing that works, especially early on.
If you've ever seen videos of triple-A titles in alpha, you'll know how slow / buggy they are. This is normal; in fact, it's desirable. And it's ...
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5
votes
Accepted
How to react properly to component field changes?
I personally would go with the event sending, because it's more explicit and easier to follow in code. Something like:
...
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4
votes
How do components access one another in a component based entity system
Your component entity system doesn't match that which was shown in the article. The article doesn't attach logic components to entities, it uses system objects which look for data components.
...
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4
votes
Would it be practical if I used composition for everything?
Composition is a tool. Always use the right tool for the job.
Of course you can use a screwdriver to hit a nail. But using a hammer might lead to faster and cleaner results.
Composition is a pretty ...
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3
votes
ECS: AI components and systems
The problem I see with this approach is that the AI module cannot be easily decoupled from the components attached to the entities. To evaluate a tree or run a state machine, it needs to know ...
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3
votes
Accepted
Where is 'game logic' implemented in component based design?
Not everything in your game must be based on the ECS pattern you're using and the game logic might be a good candidate not to.
It could be a global script.
Or, as you mention, you can implement the ...
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3
votes
Accepted
ECS - Components inside components?
First of all, there is no "right" or "wrong" way to structure a game's software architecture. Just ways which work or don't work for you.
Usually you wouldn't nest components. What you would do ...
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3
votes
Why even use coroutines in Unity?
You can do that if you want, but...
First, 10000 update calls are more expensive than one update call calling 10000 functions. This is due to the Magic Method indexing and querying logic Unity does ...
3
votes
Accepted
Unity get component throwing NullReferenceException only in standalone build
I found the problem.
It was all because of a stupid little workaround I was making. For some context, I was having problems with the new prefab workflow resetting scene references in all my levels. I ...
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3
votes
Accepted
Should fields in components in an ECS use polymorphism?
feels like I'm violating the ECS rule
There is no ECS police that will come and put you in ECS Jail. This is your architecture, you set it up how it fits your needs.
having any functionality in ...
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3
votes
Cannot decide between using a MessageBus and entities for events in my ECS game
My approach was to have a PhysicsSystem which works on entities that have a ColliderComponent/PhysicsComponent/TransformComponent...
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3
votes
How to Implement ECS Archetypes in C#?
Here is a sketch of how you can implement an archetype in C#:
...
- 139k
3
votes
Accepted
Decoupling Components
One great tool for decoupling components in Unity are events.
The high-level idea of events is that one component says "Something happened with me" and other components can choose to ...
- 122k
2
votes
Accepted
Component based architecture in TypeScript
I've got some good suggestions on Phaser forum, the solution shown by user @flyovergames was what I was looking for:
...
2
votes
Accepted
How to handle component-based objects in a game loop?
Both approaches should result in the same result, so your choice really comes down to what makes the most sense architecturally.
But first, your example for approach #2 is incorrect. Each system ...
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2
votes
Appropriate Cache Friendly Associative Container For An Entity Component System
ArcaneEngineer's advice is good, particularly for early development (to an extent - once you configure your engine to work a particular way, it can be significantly hard to rework it later).
For ...
- 148
2
votes
Accepted
Where to store contiguous arrays of components?
The solution you described is using the so called "curiously recurring template pattern", often abbreviated as CRTP and is very common in C++ programming.
This is a straightforward solution to the ...
- 1,557
2
votes
Pass data down to components
Will you have networking?
I understand that you are probably making a single player game engine. However, thinking about how to deal with the network very, very, very early in the desgin will push ...
- 28k
2
votes
In Unreal Engine 4, how do I get the component's "game object" via C++?
Use GetOwner() in the component
- 787
2
votes
Accepted
Where should I put units and items in a squad-combat ECS-based game?
As a general disclaimer and as DMGregory already stated it: The rules of ECS are not written in stone. Doing it on way has benefits, doing it another way has some others. So, you need to know, what ...
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2
votes
Component instance reference in Unreal Engine 4
To do this in Unreal C++, inside the CPP file you need to do the following:
Make sure to include the header component:
#include "Camera/CameraComponent.h"
Then in the class constructor:
...
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Only top scored, non community-wiki answers of a minimum length are eligible