ComponentCacheGenerator

A source generator that automatically generates a cache of components for Unity.

日本語版READMEはこちら

ComponentCacheGenerator provides automatic generation of component caching code for Unity by generating code to cache GetComponent<T>() retrievals using a source generator, reducing the amount of code you need to write.

Setup

Requirements

• Unity 2022.2 or later

Installation

1. Open the Package Manager from Window > Package Manager.
2. Click the "+" button > Add package from git URL.
3. Enter the following URL:

https://github.com/AnnulusGames/ComponentCacheGenerator.git?path=src/ComponentCacheGenerator/Assets/ComponentCacheGenerator

Alternatively, open Packages/manifest.json and add the following to the dependencies block:

{
    "dependencies": {
        "com.annulusgames.component-cache-generator": "https://github.com/AnnulusGames/ComponentCacheGenerator.git?path=src/ComponentCacheGenerator/Assets/ComponentCacheGenerator"
    }
}

Basic Usage

In Unity, retrieving components with GetComponent<T>() is known to be costly, so it's common practice to cache references beforehand in Awake() or Start(). Additionally, [RequireComponent(typeof(T))] is often used to prevent forgetting to add components. While these practices are necessary for performance and maintainability, they can lead to increased code verbosity as the number of components grows.

using UnityEngine;

[RequireComponent(typeof(FooComponent))]
[RequireComponent(typeof(BarComponent))]
[RequireComponent(typeof(BazComponent))]
public class SomeBehaviour : MonoBehaviour
{
    FooComponent fooComponent;
    BarComponent barComponent;
    BazComponent bazComponent;

    void Awake()
    {
        fooComponent = GetComponent<FooComponent>();
        barComponent = GetComponent<BarComponent>();
        bazComponent = GetComponent<BazComponent>();
    }

    void Update()
    {
        fooComponent.Foo();
        barComponent.Bar();
        bazComponent.Baz();
    }
}

ComponentCacheGenerator automatically generates this code using the [GenerateComponentCache] attribute.

using UnityEngine;
using ComponentCacheGenerator;

[GenerateComponentCache(typeof(FooComponent))]
[GenerateComponentCache(typeof(BarComponent))]
[GenerateComponentCache(typeof(BazComponent))]
public partial class SomeBehaviour : MonoBehaviour
{
    void Update()
    {
        fooComponent.Foo();
        barComponent.Bar();
        bazComponent.Baz();
    }
}

ComponentCacheGenerator generates properties to cache each component and a CacheComponents() method. If the target class does not have an Awake() method, one will be automatically added to the class. (Note: If the target class already has an Awake() method, you need to manually call CacheComponents().)

// Automatically added if Awake does not exist
void Awake()
{
    CacheComponents()
}

It is also possible to specify the property name of the generated cache. If not specified, the class name of the target component converted to lower camel case will be used.

using UnityEngine;
using ComponentCacheGenerator;

[GenerateComponentCache(typeof(FooComponent), "foo")]
[GenerateComponentCache(typeof(BarComponent), "bar")]
[GenerateComponentCache(typeof(BazComponent), "baz")]
public partial class SomeBehaviour : MonoBehaviour
{
    void Update()
    {
        foo.Foo();
        bar.Bar();
        baz.Baz();
    }
}

Generation Options

You can specify generation code settings by specifying values for properties in the [GenerateComponentCache] attribute.

Property	Description
SearchScope	Specifies the scope to search for components. If multiple are specified, the search will be performed in the order of Self > Children > Parent. (Default is Self)
IsRequired	If IsRequired is true, an exception will be thrown if the component is not found when CacheComponents() is called. If the search scope is Self, [RequireComponent] attribute will be automatically generated. (Default is true)

License

MIT License