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System Design

Beginner guide to event-driven game design

A practical introduction to organizing input, collisions, UI, and progression around events so your game logic stays readable.

公開日: 2026-06-26#Event#Architecture#UI#Beginner

Quick Start

Start with a tiny working version

One of the fastest ways beginners make game logic harder than it needs to be is by checking everything every frame. Many game reactions do not need constant polling.

Build it in small code pieces

1. 値を用意する

Inspectorで変更できる値と表示先を置きます。

EventDrivenTutorial.cs
csharp
    [SerializeField] private TextMeshProUGUI statusText;
    [SerializeField] private float eventCount = 1f;
    [SerializeField] private float listenerCount = 2f;
    [SerializeField] private float lastEventId = 3f;

2. 状態を変える

ボタンを押した時に、1つだけ状態を進めます。

EventDrivenTutorial.cs
csharp
    public void NextStep()
    {
        step = (step + 1) % 3;
        var label = step == 0 ? "イベントを送る" : step == 1 ? "受け取る" : "UIを更新する";
        if (statusText != null)
        {
            statusText.text = $"{label}\neventCount={eventCount:0.##}\nlistenerCount={listenerCount:0.##}\nlastEventId={lastEventId:0.##}";
        }

3. 画面に表示する

変わった結果を画面に出して確認します。

EventDrivenTutorial.cs
csharp
        if (statusText != null)
        {
            statusText.text = $"{label}\neventCount={eventCount:0.##}\nlistenerCount={listenerCount:0.##}\nlastEventId={lastEventId:0.##}";
        }
        Debug.Log($"イベント駆動の状態連携: {label}");

Complete script

EventDrivenTutorial.cs
csharp
using UnityEngine;
using TMPro;

public class EventDrivenTutorial : MonoBehaviour
{
    [SerializeField] private TextMeshProUGUI statusText;
    [SerializeField] private float eventCount = 1f;
    [SerializeField] private float listenerCount = 2f;
    [SerializeField] private float lastEventId = 3f;

    private int step;

    public void NextStep()
    {
        step = (step + 1) % 3;
        var label = step == 0 ? "イベントを送る" : step == 1 ? "受け取る" : "UIを更新する";
        if (statusText != null)
        {
            statusText.text = $"{label}\neventCount={eventCount:0.##}\nlistenerCount={listenerCount:0.##}\nlastEventId={lastEventId:0.##}";
        }
        Debug.Log($"イベント駆動の状態連携: {label}");
    }
}

Inspector

Connect the UI reference in the Inspector, then use the button to confirm each value changes.

Summary

What to take away

A practical introduction to organizing input, collisions, UI, and progression around events so your game logic stays readable.

The page is designed to help you move from reading to a small practical decision. Use the checklist above before jumping into the next related article.

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