Render stuff with pixels!

PixelRenderer.cs

using System.Collections.Generic;
using Code.Events.EventTypes.Battle;
using Code.Events.EventTypes.World;
using Code.Utils;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

namespace Code.Game.CameraUtils
{
    public class PixelRenderer : SingletonMonoBehaviour<PixelRenderer>
    {
        public Camera Camera;
        public Camera UICamera;
        public Canvas Canvas;
        public RawImage GameImage;

        private int cachedScreenWidth = 0;
        private int cachedScreenHeight = 0;

        public RenderTexture renderTexture;
        public Material RenderTextureMaterial;

        public void Awake()
        {
            DontDestroyOnLoad(this.gameObject);

            AddListener<WorldReadyEvent>(OnWorldReady);
            AddListener<BattleReadyEvent>(OnBattleReady);

            GrabCamera();
        }

        public void Update()
        {
            if (cachedScreenWidth != Screen.width || cachedScreenHeight != Screen.height)
            {
                UpdateEverything();
            }
        }

        public void OnWorldReady(WorldReadyEvent worldReadyEvent)
        {
            GrabCamera();
            UICamera.gameObject.SetActive(true);
            Canvas.gameObject.SetActive(true);
            UpdateEverything();
        }

        public void OnBattleReady(BattleReadyEvent worldReadyEvent)
        {
            UICamera.gameObject.SetActive(false);
            Canvas.gameObject.SetActive(false);
        }

        public void UpdateEverything()
        {
            if (GameController.Instance == null)
            {
                return;
            }

            GrabCamera();

            GameImage.gameObject.SetActive(false);

            int scale = GameController.Instance.GetGameScale();
            int renderedWidth = (int)Mathf.Ceil((float)Screen.width / (float)scale);
            int renderedHeight = (int)Mathf.Ceil((float)Screen.height / (float)scale);

            renderTexture = new RenderTexture(
                renderedWidth,
                renderedHeight,
                24,
                RenderTextureFormat.ARGB32
            );

            renderTexture.filterMode = FilterMode.Point;
            renderTexture.wrapMode = TextureWrapMode.Clamp;
            renderTexture.useMipMap = false;
            renderTexture.autoGenerateMips = false;
            renderTexture.hideFlags = HideFlags.DontSave;

            RenderTextureMaterial.mainTexture = renderTexture;

            Camera.orthographicSize = renderedHeight / 2f;
            Camera.targetTexture = renderTexture;

            GameImage.material = RenderTextureMaterial;

            RectTransform gameImageRectTransform = GameImage.GetComponent<RectTransform>();
            gameImageRectTransform.sizeDelta = new Vector2(
                renderedWidth,
                renderedHeight
            );

            gameImageRectTransform.localScale = new Vector3(
                scale,
                scale,
                1
                );

            cachedScreenWidth = Screen.width;
            cachedScreenHeight = Screen.height;

            GameImage.gameObject.SetActive(true);
        }

        private void GrabCamera()
        {
            if (Camera == null)
            {
                GameObject mainCamera = GameObject.Find("Main Camera");
                if (mainCamera != null)
                {
                    Camera = mainCamera.GetComponent<Camera>();
                }
            }
        }
    }
}