DEV Community: Piler

[Unity] Delegate and loop related issue

Piler — Mon, 06 Jan 2025 07:42:14 +0000

    void Start()
    {
        for (int i = 0; i < 3; i++)
        {
            button.onClick.AddListener(() => Foo(i));
        }
    }

    void Foo(int i)
    {
        Debug.Log(i);
    }

When you write code like this, you expected the output is

0
1
2

but the result is

3
3
3

The reason is when using delegate, variable is captured by reference. (Closure and Captured Variable Behavior)

Solution:

    void Start()
    {
        for (int i = 0; i < 3; i++)
        {
            int temp = i;
            button.onClick.AddListener(() => Foo(temp));
        }
    }

    void Foo(int i)
    {
        Debug.Log(i);
    }

[Design Pattern] Observer pattern for achievement System

Piler — Thu, 02 Jan 2025 06:52:31 +0000

I would use Node.js as example.

eventBus.js

const EventEmitter = require('events');
const eventBus = new EventEmitter();
module.exports = eventBus;

account.js

const eventBus = require("../eventBus");
function register(uid) {
    eventBus.emit("onRegister", { uid, time: Date.now() });
}

gacha.js

const eventBus = require("../eventBus");
function gacha(uid) {
    eventBus.emit("onGacha", { uid, grade});

}

achievement.js

const eventBus = require("../eventBus");
eventBus.on("onRegister", (args) => {
  createUserAchievements(args.uid);
});

eventBus.on("onGacha", (args) => {
  updateProgress(args.uid, `gacha`);
  updateProgress(args.uid, `gacha:${args.grade}`);

});

async function updateProgress(uid, type, count = 1) {
  console.log(`[userId:${uid}] updateProgress: ${type}`);

  try {
    // Fetch user achievements
    const userAchievementsData = await UserAchievement.findOne({ userId: uid });
    if (!userAchievementsData || !Array.isArray(userAchievementsData.achievements)) {
      console.error(`[userId:${uid}] No achievements data found`);
      return;
    }

    // Iterate through user achievements
    let hasUpdates = false;
    for (const userAchievement of userAchievementsData.achievements) {
      // Skip achievements not in progress
      if (userAchievement.status !== "in_progress") continue;

      // Fetch the related achievement
      const achievement = await Achievement.findById(userAchievement.achievementId);
      if (!achievement) {
        console.error(`[userId:${uid}] Achievement not found: ${userAchievement.achievementId}`);
        continue;
      }

      // Update progress if type matches
      if (type === achievement.requirements.type) {
        userAchievement.progress += count;
        hasUpdates = true;

        // Check for completion
        if (userAchievement.progress >= achievement.requirements.count) {
          userAchievement.status = "completed";
          console.log(`[userId:${uid}] Achievement "${achievement.en}" completed`);
        }
      }
    }

    // Save updates if any changes were made
    if (hasUpdates) {
      await userAchievementsData.save();
      console.log(`[userId:${uid}] Progress updated successfully`);
    } else {
      console.log(`[userId:${uid}] No progress updates required`);
    }
  } catch (error) {
    console.error(`[userId:${uid}] Error updating progress:`, error);
  }
}

[Unity] Two texture transition shader

Piler — Thu, 02 Jan 2025 03:15:51 +0000

Target Effect:

Create variables: two texture and origin(float)

Create a binary mask
Create a reversed binary mask
Multiple the binary mask and texture, then add them together
Done! You can modify the origin to do transition!

[Unity] use UnityWebRequest by async/without coroutine

Piler — Mon, 16 Dec 2024 07:02:31 +0000

UnityWebRequestAsync class:

using System.Text;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.Networking;

public static class UnityWebRequestAsync
{
    public async static Task<string> Request(string url, RequestMethod method, string body = null)
    {
        if (string.IsNullOrEmpty(url))
        {
            Debug.LogError("URL cannot be null or empty.");
            return null;
        }

        string[] arr = new string[]
        {
            "GET",
            "POST",
            "PUT",
            "DELETE"
        };

        using UnityWebRequest request = new UnityWebRequest(url, arr[(int)method]);
        try
        {
            // Setup
            if (method != RequestMethod.GET && body != null)
            {
                byte[] jsonDataBytes = Encoding.UTF8.GetBytes(body);
                request.uploadHandler = new UploadHandlerRaw(jsonDataBytes);
            }

            request.downloadHandler = new DownloadHandlerBuffer();
            request.SetRequestHeader("Content-Type", "application/json");
            request.SetRequestHeader("version", Application.version);

            // Send request
            var operation = request.SendWebRequest();
            while (!operation.isDone)
            {
                await Task.Yield();
            }

            // Check Result
            if (request.result == UnityWebRequest.Result.Success)
            {
                return request.downloadHandler.text;
            }
            else
            {
                Debug.LogError($"Request failed: {request.error} (HTTP {request.responseCode})");
                return null;
            }
        }
        catch (System.Exception ex)
        {
            Debug.LogError($"Exception occurred during request: {ex.Message}");
            return null;
        }
    }
}

public enum RequestMethod
{
    GET,
    POST, 
    PUT, 
    DELETE
}

Usage:

string result = await UnityWebRequestAsync.Request(url, RequestMethod.GET);

[Unity] Reducing loading time while entering play mode

Piler — Wed, 16 Oct 2024 06:52:00 +0000

Go to Project Settings->Editor
Enable "Enter Play Mode Options", Let "Reload Domain" and "Reload Scene".

*After the above settings, static variables will not be reset while entering play mode.

[Unity] Fix video player start with black screen in Android

Piler — Fri, 02 Aug 2024 07:29:01 +0000

Solution: set the render texture initialization color to transparent.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Video;

public class VideoPlayerFixBlackScreen : MonoBehaviour
{
    public int width = 848;
    public int height = 480;

    public RawImage rawImage;
    VideoPlayer vp;

    void Start()
    {
        vp = GetComponent<VideoPlayer>();

        var renderTexture = new CustomRenderTexture(width, height);
        renderTexture.initializationColor = new Color(0f, 0f, 0f, 0f);
        vp.targetTexture = renderTexture;

        rawImage.texture = renderTexture;
    }
}

[Unity] How to create a conveyor?

Piler — Thu, 20 Jun 2024 07:29:30 +0000

public class Conveyor : MonoBehaviour
{
    public float speed = 1f;
    Rigidbody rb;

    void Start()
    {
        rb = GetComponent<Rigidbody>();
    }

    private void FixedUpdate()
    {
        Vector3 pos = rb.position;
        rb.position += -transform.forward * speed * Time.fixedDeltaTime;
        rb.MovePosition(pos);
    }
}

Reference: https://www.youtube.com/watch?v=hC1QZ0h4oco

[Unity] Dropdown menu with search

Piler — Wed, 19 Jun 2024 07:35:22 +0000

using UnityEditor;
using UnityEngine;
using UnityEditor.IMGUI.Controls;

class WeekdaysDropdown : AdvancedDropdown
{
    public WeekdaysDropdown(AdvancedDropdownState state) : base(state)
    {
    }

    protected override AdvancedDropdownItem BuildRoot()
    {
        var root = new AdvancedDropdownItem("Weekdays");

        var firstHalf = new AdvancedDropdownItem("First half");
        var secondHalf = new AdvancedDropdownItem("Second half");
        var weekend = new AdvancedDropdownItem("Weekend");

        firstHalf.AddChild(new AdvancedDropdownItem("Monday"));
        firstHalf.AddChild(new AdvancedDropdownItem("Tuesday"));
        secondHalf.AddChild(new AdvancedDropdownItem("Wednesday"));
        secondHalf.AddChild(new AdvancedDropdownItem("Thursday"));
        weekend.AddChild(new AdvancedDropdownItem("Friday"));
        weekend.AddChild(new AdvancedDropdownItem("Saturday"));
        weekend.AddChild(new AdvancedDropdownItem("Sunday"));

        root.AddChild(firstHalf);
        root.AddChild(secondHalf);
        root.AddChild(weekend);

        return root;
    }
}

public class AdvancedDropdownTestWindow : EditorWindow
{
    void OnGUI()
    {
        var rect = GUILayoutUtility.GetRect(new GUIContent("Show"), EditorStyles.toolbarButton);
        if (GUI.Button(rect, new GUIContent("Show"), EditorStyles.toolbarButton))
        {
            var dropdown = new WeekdaysDropdown(new AdvancedDropdownState());
            dropdown.Show(rect);
        }
    }
}

[Unity] Create Dropdown in PropertyDrawer

Piler — Wed, 19 Jun 2024 07:34:45 +0000

Offical example code:

public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
{
    index = EditorGUILayout.Popup(index, options);
}

If you want to update property value after select:

public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
{
  int index = Array.IndexOf(options, property.objectReferenceValue);

  if (index!= -1)
  {
      index = EditorGUI.Popup(position, label.text, index, options);
      property.objectReferenceValue = options[index];
  }
}

[Unity] Remove non-visible characters/Weird string behavior

Piler — Wed, 19 Jun 2024 07:16:20 +0000

using System;
using System.Text.RegularExpressions;

string input = "Hello\u200B World\u200C!"; // Example string with non-visible characters

string result = Regex.Replace(input, @"\p{C}+", ""); // Remove non-visible characters

Console.WriteLine(result); // Output: Hello World!

[Unity] Fix HDRP UI affected by Anti-Aliasing

Piler — Wed, 19 Jun 2024 07:15:50 +0000

Project Settings -> Quality -> HDRP -> Custom Pass, Enable it
Create a Custom Pass Volume as below

[Unity] TextMeshPro Chinese Font

Piler — Wed, 19 Jun 2024 07:08:16 +0000

Unity version: 2022.3 LTS

Prepare a Chinese font file (e.g. ttf file)
Select your font file in Project view.
Asset->Create->TextMeshPro->Font Asset
Select the font asset just created in Project view.
Set Altas Width & Altas Height to higher resolution. (e.g. 4096)

Done!

Thanks to Paul