Automatically logs things to the game view in Flax Engine.

OutputLogger.cs

using System;
using System.Collections.Generic;
using FlaxEngine;
using FlaxEngine.GUI;

namespace Game;

public class OutputLogger : GamePlugin
{
    private const bool ENABLED = true;

    private VerticalPanel _logs;
    private class LogMessage
    {
        public float Time;
        public Label Log;
    }

    private List<LogMessage> _logMessages;

    public override void Initialize()
    {
        if (!ENABLED)
            return;

        base.Initialize();
        _logMessages = new List<LogMessage>();
        _logs = new VerticalPanel
        {
            Parent = RootControl.GameRoot,
            AnchorPreset = AnchorPresets.TopLeft,
            X = 0,
            Y = 0,
            Width = Screen.Size.X / 4,
            Height = Screen.Size.Y / 4,
            //BackgroundColor = Color.White,
        };
        Debug.Logger.LogHandler.SendLog += LoggerTriggered;
        Scripting.Update += Update;
    }

    private void Trim()
    {
        if (_logMessages.Count > 4)
        {
            DeleteLog(0);
        }
    }

    private void DeleteLog(int index)
    {
        _logMessages[index].Log.Parent = null;
        _logMessages.RemoveAt(index);
    }

    private void LoggerTriggered(LogType level, string msg, FlaxEngine.Object obj, string stackTrace)
    {
        Label log = _logs.AddChild<Label>();
        string loggingOutput = msg.Substring(0, Math.Min(25, msg.Length));
        if (msg.Length > 25)
            loggingOutput += "...";

        log.Text = loggingOutput;
        log.Font.Size = 12;
        log.HorizontalAlignment = TextAlignment.Near;
        log.Height = 16;

        _logMessages.Add(new LogMessage
        {
            Log = log,
            Time = 0,
        });
        Trim();
    }

    public override void Deinitialize()
    {
        if (!ENABLED)
            return;

        base.Deinitialize();
        Scripting.Update -= Update;
        Debug.Logger.LogHandler.SendLog -= LoggerTriggered;
        _logs.Parent = null;
    }

    private void Update()
    {
        int count = 0;
        foreach (LogMessage log in _logMessages)
        {
            log.Time += Time.DeltaTime;
            if (log.Time > 10)
            {
                float remaining = (log.Time - 10) / 5;
                remaining = 1 - remaining;

                Color color = log.Log.TextColor;
                color.A = remaining;
                log.Log.TextColor = color;
            }

            if (log.Time > 15)
            {
                count++;
            }
        }

        for (int i = 0; i < count; i++)
        {
            DeleteLog(0);
        }
    }
}