FullscreenQuadRenderer

// This is a modified version of a Scriptable Render Pass written by Harry Heath.
// Twitter: https://twitter.com/harryh___h/status/1328024692431540224
// Pastebin: https://pastebin.com/LstBHRZF

// The original code was used in a recreation of a Mako illustration:
// https://twitter.com/harryh___h/status/1328006632102526976

using UnityEngine;
using UnityEngine.Rendering;
using UnityEngine.Rendering.Universal;

public class FullscreenQuadRenderer : ScriptableRenderPass
{
    string m_ProfilerTag;
    private Material _material;

    private ScriptableRenderer _renderer;
    private bool _isDepth;

    int textureId = -1;
    RenderTargetIdentifier _texture;
    bool _newTexture;

    public FullscreenQuadRenderer(string name)
    {
        renderPassEvent = RenderPassEvent.BeforeRenderingTransparents;
        m_ProfilerTag = name;
    }

    public void Init(Material initMaterial, ScriptableRenderer newRenderer, bool depth)
    {
        _material = initMaterial;
        _renderer = newRenderer;
        textureId = -1;
        _isDepth = depth;
    }

    public void Init(Material initMaterial, string textureName, bool newTexture)
    {
        _material = initMaterial;
        textureId = Shader.PropertyToID(textureName);
        _texture = new RenderTargetIdentifier(textureId);
        _renderer = null;
        _newTexture = newTexture;
    }

    public override void Configure(CommandBuffer cmd, RenderTextureDescriptor cameraTextureDescriptor)
    {
        if (textureId != -1 && _newTexture)
        {
            cmd.GetTemporaryRT(textureId, cameraTextureDescriptor.width, cameraTextureDescriptor.height, 24, FilterMode.Point,
                RenderTextureFormat.ARGBFloat);
        }
        else if (textureId == -1)
        {
            _texture = _isDepth ? _renderer.cameraDepthTarget : _renderer.cameraColorTarget;
        }

        ConfigureTarget(_texture);
        if (_newTexture) ConfigureClear(ClearFlag.All, Color.black);
    }

    public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
    {
        if (_material == null) return;

        CommandBuffer cmd = CommandBufferPool.Get(m_ProfilerTag);
        Camera camera = renderingData.cameraData.camera;

        cmd.SetGlobalTexture("_MainTex", _texture);
        cmd.SetViewProjectionMatrices(Matrix4x4.identity, Matrix4x4.identity);
        cmd.DrawMesh(RenderingUtils.fullscreenMesh, Matrix4x4.identity, _material);
        cmd.SetViewProjectionMatrices(camera.worldToCameraMatrix, camera.projectionMatrix);

        context.ExecuteCommandBuffer(cmd);
        CommandBufferPool.Release(cmd);
    }

    public override void FrameCleanup(CommandBuffer cmd)
    {
        if (textureId != -1 && _newTexture) cmd.ReleaseTemporaryRT(textureId);
    }
}