Scriptable Renderer Feature that applies a material to a whole screen

FullscreenShaderFeature.cs

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

public class FullscreenShaderFeature : ScriptableRendererFeature
{
    [SerializeField]
    private Material material;

    class CustomRenderPass : ScriptableRenderPass
    {
        [SerializeField]
        private Material material;

        private RTHandle tempTex, srcTex;

        public CustomRenderPass(Material mat) : base()
        {
            material = mat;
        }

        public override void OnCameraSetup(CommandBuffer cmd, ref RenderingData renderingData)
        {
            srcTex = renderingData.cameraData.renderer.cameraColorTargetHandle;
            tempTex = RTHandles.Alloc(new RenderTargetIdentifier("_TempTex"), "_TempTex");
        }

        public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
        {
            CommandBuffer cmd = CommandBufferPool.Get("FullscreenShaderFeature");

            RenderTextureDescriptor desc = renderingData.cameraData.cameraTargetDescriptor;
            desc.depthBufferBits = 0;

            cmd.GetTemporaryRT(Shader.PropertyToID(tempTex.name), desc, FilterMode.Point);

            Blit(cmd, srcTex, tempTex, material);
            Blit(cmd, tempTex, srcTex);

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

        public override void OnCameraCleanup(CommandBuffer cmd)
        {
            tempTex.Release();
        }
    }

    CustomRenderPass m_ScriptablePass;

    public override void Create()
    {
        m_ScriptablePass = new CustomRenderPass(material);
        m_ScriptablePass.renderPassEvent = RenderPassEvent.BeforeRenderingPostProcessing;
    }

    public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
    {
        renderer.EnqueuePass(m_ScriptablePass);
    }
}