ScriptableRenderPipeline/ScriptableRenderPipeline/HDRenderPipeline/HDRenderPipeline.cs

using System.Collections.Generic;
using UnityEngine.Rendering;
using System;
using System.Linq;
using UnityEngine.Rendering.PostProcessing;
using UnityEngine.Experimental.Rendering.HDPipeline.TilePass;

#if UNITY_EDITOR
using UnityEditor;
#endif

namespace UnityEngine.Experimental.Rendering.HDPipeline
{
    [Serializable]
    public class RenderingSettings
    {
        public bool useForwardRenderingOnly = false; // TODO: Currently there is no way to strip the extra forward shaders generated by the shaders compiler, so we can switch dynamically.
        public bool useDepthPrepass = false;

        // We have to fall back to forward-only rendering when scene view is using wireframe rendering mode --
        // as rendering everything in wireframe + deferred do not play well together
        public bool ShouldUseForwardRenderingOnly()
        {
            return useForwardRenderingOnly || GL.wireframe;
        }
    }

    // This holds all the matrix data we need for rendering, including data from the previous frame
    // (which is the main reason why we need to keep them around for a minimum of one frame).
    // HDCameras are automatically created & updated from a source camera and will be destroyed if
    // not used during a frame.
    public class HDCamera
    {
        public Matrix4x4 viewMatrix;
        public Matrix4x4 projMatrix;
        public Matrix4x4 nonJitteredProjMatrix;
        public Vector4   screenSize;
        public Vector4[] frustumPlaneEquations;
        public Camera    camera;

        public Matrix4x4 viewProjMatrix
        {
            get { return projMatrix * viewMatrix; }
        }

        public Matrix4x4 nonJitteredViewProjMatrix
        {
            get { return nonJitteredProjMatrix * viewMatrix; }
        }

        public bool isFirstFrame
        {
            get { return m_FirstFrame; }
        }

        public Vector4 invProjParam
        {
            // Ref: An Efficient Depth Linearization Method for Oblique View Frustums, Eq. 6.
            get { var p = projMatrix; return new Vector4(p.m20 / (p.m00 * p.m23), p.m21 / (p.m11 * p.m23), -1.0f / p.m23, (-p.m22 + p.m20 * p.m02 / p.m00 + p.m21 * p.m12 / p.m11) / p.m23); }
        }

        // View-projection matrix from the previous frame.
        public Matrix4x4 prevViewProjMatrix;

        // We need to keep track of these when camera relative rendering is enabled so we can take
        // camera translation into account when generating camera motion vectors
        public Vector3 cameraPos;
        public Vector3 prevCameraPos;

        // The only way to reliably keep track of a frame change right now is to compare the frame
        // count Unity gives us. We need this as a single camera could be rendered several times per
        // frame and some matrices only have to be computed once. Realistically this shouldn't
        // happen, but you never know...
        int m_LastFrameActive;

        // Always true for cameras that just got added to the pool - needed for previous matrices to
        // avoid one-frame jumps/hiccups with temporal effects (motion blur, TAA...)
        bool m_FirstFrame;

        public HDCamera(Camera cam)
        {
            camera = cam;
            frustumPlaneEquations = new Vector4[6];
            Reset();
        }

        public void Update(PostProcessLayer postProcessLayer)
        {
            // If TAA is enabled projMatrix will hold a jittered projection matrix. The original,
            // non-jittered projection matrix can be accessed via nonJitteredProjMatrix.
            bool taaEnabled = camera.cameraType == CameraType.Game
                && Utilities.IsTemporalAntialiasingActive(postProcessLayer);

            Matrix4x4 nonJitteredCameraProj = camera.projectionMatrix;
            Matrix4x4 cameraProj = taaEnabled
                ? postProcessLayer.temporalAntialiasing.GetJitteredProjectionMatrix(camera)
                : nonJitteredCameraProj;

            // The actual projection matrix used in shaders is actually massaged a bit to work across all platforms
            // (different Z value ranges etc.)
            Matrix4x4 gpuProj = GL.GetGPUProjectionMatrix(cameraProj, true); // Had to change this from 'false'
            Matrix4x4 gpuView = camera.worldToCameraMatrix;
            Matrix4x4 gpuNonJitteredProj = GL.GetGPUProjectionMatrix(nonJitteredCameraProj, true);

            Vector3 pos = camera.transform.position;

            if (ShaderConfig.s_CameraRelativeRendering != 0)
            {
                // Zero out the translation component.
                gpuView.SetColumn(3, new Vector4(0, 0, 0, 1));
            }

            Matrix4x4 gpuVP = gpuNonJitteredProj * gpuView;

            // A camera could be rendered multiple times per frame, only updates the previous view proj & pos if needed
            if (m_LastFrameActive != Time.frameCount)
            {
                if (m_FirstFrame)
                {
                    prevCameraPos = pos;
                    prevViewProjMatrix = gpuVP;
                }
                else
                {
                    prevCameraPos = cameraPos;
                    prevViewProjMatrix = nonJitteredViewProjMatrix;
                }

                m_FirstFrame = false;
            }

            viewMatrix = gpuView;
            projMatrix = gpuProj;
            nonJitteredProjMatrix = gpuNonJitteredProj;
            cameraPos = pos;
            screenSize = new Vector4(camera.pixelWidth, camera.pixelHeight, 1.0f / camera.pixelWidth, 1.0f / camera.pixelHeight);

            Plane[] planes = GeometryUtility.CalculateFrustumPlanes(viewProjMatrix);

            for (int i = 0; i < 6; i++)
            {
                frustumPlaneEquations[i] = new Vector4(planes[i].normal.x, planes[i].normal.y, planes[i].normal.z, planes[i].distance);
            }

            m_LastFrameActive = Time.frameCount;
        }

        public void Reset()
        {
            m_LastFrameActive = -1;
            m_FirstFrame = true;
        }

        static Dictionary<Camera, HDCamera> m_Cameras = new Dictionary<Camera, HDCamera>();
        static List<Camera> m_Cleanup = new List<Camera>(); // Recycled to reduce GC pressure

        // Grab the HDCamera tied to a given Camera and update it.
        public static HDCamera Get(Camera camera, PostProcessLayer postProcessLayer)
        {
            HDCamera hdcam;

            if (!m_Cameras.TryGetValue(camera, out hdcam))
            {
                hdcam = new HDCamera(camera);
                m_Cameras.Add(camera, hdcam);
            }

            hdcam.Update(postProcessLayer);
            return hdcam;
        }

        // Look for any camera that hasn't been used in the last frame and remove them for the pool.
        public static void CleanUnused()
        {
            int frameCheck = Time.frameCount - 1;

            foreach (var kvp in m_Cameras)
            {
                if (kvp.Value.m_LastFrameActive != frameCheck)
                    m_Cleanup.Add(kvp.Key);
            }

            foreach (var cam in m_Cleanup)
                m_Cameras.Remove(cam);

            m_Cleanup.Clear();
        }

        public void SetupGlobalParams(CommandBuffer cmd)
        {
            cmd.SetGlobalMatrix(HDShaderIDs._ViewMatrix,                viewMatrix);
            cmd.SetGlobalMatrix(HDShaderIDs._InvViewMatrix,             viewMatrix.inverse);
            cmd.SetGlobalMatrix(HDShaderIDs._ProjMatrix,                projMatrix);
            cmd.SetGlobalMatrix(HDShaderIDs._InvProjMatrix,             projMatrix.inverse);
            cmd.SetGlobalMatrix(HDShaderIDs._NonJitteredViewProjMatrix, nonJitteredViewProjMatrix);
            cmd.SetGlobalMatrix(HDShaderIDs._ViewProjMatrix,            viewProjMatrix);
            cmd.SetGlobalMatrix(HDShaderIDs._InvViewProjMatrix,         viewProjMatrix.inverse);
            cmd.SetGlobalVector(HDShaderIDs._InvProjParam,              invProjParam);
            cmd.SetGlobalVector(HDShaderIDs._ScreenSize,                screenSize);
            cmd.SetGlobalMatrix(HDShaderIDs._PrevViewProjMatrix,        prevViewProjMatrix);
            cmd.SetGlobalVectorArray(HDShaderIDs._FrustumPlanes,        frustumPlaneEquations);
        }

        // Does not modify global settings. Used for shadows, low res. rendering, etc.
        public void OverrideGlobalParams(Material material)
        {
            material.SetMatrix(HDShaderIDs._ViewMatrix,                viewMatrix);
            material.SetMatrix(HDShaderIDs._InvViewMatrix,             viewMatrix.inverse);
            material.SetMatrix(HDShaderIDs._ProjMatrix,                projMatrix);
            material.SetMatrix(HDShaderIDs._InvProjMatrix,             projMatrix.inverse);
            material.SetMatrix(HDShaderIDs._NonJitteredViewProjMatrix, nonJitteredViewProjMatrix);
            material.SetMatrix(HDShaderIDs._ViewProjMatrix,            viewProjMatrix);
            material.SetMatrix(HDShaderIDs._InvViewProjMatrix,         viewProjMatrix.inverse);
            material.SetVector(HDShaderIDs._InvProjParam,              invProjParam);
            material.SetVector(HDShaderIDs._ScreenSize,                screenSize);
            material.SetMatrix(HDShaderIDs._PrevViewProjMatrix,        prevViewProjMatrix);
            material.SetVectorArray(HDShaderIDs._FrustumPlanes,        frustumPlaneEquations);
        }

        public void SetupComputeShader(ComputeShader cs, CommandBuffer cmd)
        {
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._ViewMatrix,                viewMatrix);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._InvViewMatrix,             viewMatrix.inverse);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._ProjMatrix,                projMatrix);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._InvProjMatrix,             projMatrix.inverse);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._NonJitteredViewProjMatrix, nonJitteredViewProjMatrix);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._ViewProjMatrix,            viewProjMatrix);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._InvViewProjMatrix,         viewProjMatrix.inverse);
            cmd.SetComputeVectorParam(cs, HDShaderIDs._InvProjParam,              invProjParam);
            cmd.SetComputeVectorParam(cs, HDShaderIDs._ScreenSize,                screenSize);
            cmd.SetComputeMatrixParam(cs, HDShaderIDs._PrevViewProjMatrix,        prevViewProjMatrix);
            cmd.SetComputeVectorArrayParam(cs, HDShaderIDs._FrustumPlanes,        frustumPlaneEquations);
            // Copy values set by Unity which are not configured in scripts.
            cmd.SetComputeVectorParam(cs, HDShaderIDs.unity_OrthoParams,    Shader.GetGlobalVector(HDShaderIDs.unity_OrthoParams));
            cmd.SetComputeVectorParam(cs, HDShaderIDs._ProjectionParams,    Shader.GetGlobalVector(HDShaderIDs._ProjectionParams));
            cmd.SetComputeVectorParam(cs, HDShaderIDs._ScreenParams,        Shader.GetGlobalVector(HDShaderIDs._ScreenParams));
            cmd.SetComputeVectorParam(cs, HDShaderIDs._ZBufferParams,       Shader.GetGlobalVector(HDShaderIDs._ZBufferParams));
            cmd.SetComputeVectorParam(cs, HDShaderIDs._WorldSpaceCameraPos, Shader.GetGlobalVector(HDShaderIDs._WorldSpaceCameraPos));
        }
    }

    public class GBufferManager
    {
        public const int MaxGbuffer = 8;

        public void SetBufferDescription(int index, string stringId, RenderTextureFormat inFormat, RenderTextureReadWrite inSRGBWrite)
        {
            IDs[index] = Shader.PropertyToID(stringId);
            RTIDs[index] = new RenderTargetIdentifier(IDs[index]);
            formats[index] = inFormat;
            sRGBWrites[index] = inSRGBWrite;
        }

        public void InitGBuffers(int width, int height, CommandBuffer cmd)
        {
            for (int index = 0; index < gbufferCount; index++)
            {
                cmd.GetTemporaryRT(IDs[index], width, height, 0, FilterMode.Point, formats[index], sRGBWrites[index]);
            }
        }

        private RenderTargetIdentifier[] m_ColorMRTs;
        public RenderTargetIdentifier[] GetGBuffers()
        {
            if (m_ColorMRTs == null || m_ColorMRTs.Length != gbufferCount)
                m_ColorMRTs = new RenderTargetIdentifier[gbufferCount];

            for (int index = 0; index < gbufferCount; index++)
            {
                m_ColorMRTs[index] = RTIDs[index];
            }

            return m_ColorMRTs;
        }

        public int gbufferCount { get; set; }
        int[] IDs = new int[MaxGbuffer];
        RenderTargetIdentifier[] RTIDs = new RenderTargetIdentifier[MaxGbuffer];
        RenderTextureFormat[] formats = new RenderTextureFormat[MaxGbuffer];
        RenderTextureReadWrite[] sRGBWrites = new RenderTextureReadWrite[MaxGbuffer];
    }

    public partial class HDRenderPipeline : RenderPipeline
    {
        readonly HDRenderPipelineAsset m_Asset;

        readonly RenderPipelineMaterial m_DeferredMaterial;
        readonly List<RenderPipelineMaterial> m_MaterialList = new List<RenderPipelineMaterial>();

        readonly GBufferManager m_gbufferManager = new GBufferManager();

        Material m_CopyStencilForSplitLighting;
        Material m_CopyStencilForRegularLighting;

        // Various set of material use in render loop
        ComputeShader m_SubsurfaceScatteringCS { get { return m_Asset.renderPipelineResources.subsurfaceScatteringCS; } }
        int m_SubsurfaceScatteringKernel;
        Material m_CombineLightingPass;
        // Old SSS Model >>>
        Material m_SssVerticalFilterPass;
        Material m_SssHorizontalFilterAndCombinePass;
        // <<< Old SSS Model

        Material m_CameraMotionVectorsMaterial;

        Material m_DebugViewMaterialGBuffer;
        Material m_DebugDisplayLatlong;
        Material m_DebugFullScreen;

        // Various buffer
        readonly int m_CameraColorBuffer;
        readonly int m_CameraSssDiffuseLightingBuffer;
        // Old SSS Model >>>
        readonly int m_CameraFilteringBuffer;
        // <<< Old SSS Model
        readonly int m_VelocityBuffer;
        readonly int m_DistortionBuffer;

        // 'm_CameraColorBuffer' does not contain diffuse lighting of SSS materials until the SSS pass. It is stored within 'm_CameraSssDiffuseLightingBuffer'.
        readonly RenderTargetIdentifier m_CameraColorBufferRT;
        readonly RenderTargetIdentifier m_CameraSssDiffuseLightingBufferRT;
        // Old SSS Model >>>
        readonly RenderTargetIdentifier m_CameraFilteringBufferRT;
        // <<< Old SSS Model
        readonly RenderTargetIdentifier m_VelocityBufferRT;
        readonly RenderTargetIdentifier m_DistortionBufferRT;

        private RenderTexture m_CameraDepthStencilBuffer = null;
        private RenderTexture m_CameraDepthBufferCopy = null;
        private RenderTexture m_CameraStencilBufferCopy = null;
        private RenderTexture m_HTile = null;                   // If the hardware does not expose it, we compute our own, optimized to only contain the SSS bit

        private RenderTargetIdentifier m_CameraDepthStencilBufferRT;
        private RenderTargetIdentifier m_CameraDepthBufferCopyRT;
        private RenderTargetIdentifier m_CameraStencilBufferCopyRT;
        private RenderTargetIdentifier m_HTileRT;
        
        // Post-processing context and screen-space effects (recycled on every frame to avoid GC alloc)
        readonly PostProcessRenderContext m_PostProcessContext;
        readonly ScreenSpaceAmbientOcclusionEffect m_SsaoEffect;

        // Stencil usage in HDRenderPipeline.
        // Currently we use only 2 bits to identify the kind of lighting that is expected from the render pipeline
        // Usage is define in LightDefinitions.cs
        [Flags]
        public enum StencilBitMask
        {
            Clear    = 0,                    // 0x0
            Lighting = 3,                    // 0x3  - 2 bit
            All      = 255                   // 0xFF - 8 bit
        }

        // Detect when windows size is changing
        int m_CurrentWidth;
        int m_CurrentHeight;

        // Use to detect frame changes
        int m_FrameCount;

        public int GetCurrentShadowCount() { return m_LightLoop.GetCurrentShadowCount(); }
        public int GetShadowAtlasCount() { return m_LightLoop.GetShadowAtlasCount(); }

        readonly SkyManager m_SkyManager = new SkyManager();
        readonly LightLoop m_LightLoop = new LightLoop();
        readonly ShadowSettings m_ShadowSettings = new ShadowSettings();

        // Debugging
        MaterialPropertyBlock m_SharedPropertyBlock = new MaterialPropertyBlock();
        public DebugDisplaySettings m_DebugDisplaySettings = new DebugDisplaySettings();
        private int m_DebugFullScreenTempRT;
        private bool m_FullScreenDebugPushed = false;

        public SubsurfaceScatteringSettings sssSettings
        {
            get { return m_Asset.sssSettings; }
        }

        private CommonSettings.Settings m_CommonSettings = CommonSettings.Settings.s_Defaultsettings;
        private SkySettings m_SkySettings = null;
        private ScreenSpaceAmbientOcclusionSettings.Settings m_SsaoSettings = ScreenSpaceAmbientOcclusionSettings.Settings.s_Defaultsettings;

        public CommonSettings.Settings commonSettingsToUse
        {
            get
            {
                if (CommonSettingsSingleton.overrideSettings)
                    return CommonSettingsSingleton.overrideSettings.settings;

                return m_CommonSettings;
            }
        }

        public SkySettings skySettingsToUse
        {
            get
            {
                if (SkySettingsSingleton.overrideSettings)
                    return SkySettingsSingleton.overrideSettings;

                return m_SkySettings;
            }
        }

        public ScreenSpaceAmbientOcclusionSettings.Settings ssaoSettingsToUse
        {
            get
            {
                if (ScreenSpaceAmbientOcclusionSettingsSingleton.overrideSettings)
                    return ScreenSpaceAmbientOcclusionSettingsSingleton.overrideSettings.settings;

                return m_SsaoSettings;
            }
        }

        public HDRenderPipeline(HDRenderPipelineAsset asset)
        {
            m_Asset = asset;

            // Scan material list and assign it
            m_MaterialList = Utilities.GetRenderPipelineMaterialList();
            // Find first material that have non 0 Gbuffer count and assign it as deferredMaterial
            m_DeferredMaterial = null;
            foreach (RenderPipelineMaterial material in m_MaterialList)
            {
                if (material.GetMaterialGBufferCount() > 0)
                {
                    m_DeferredMaterial = material;
                }
            }

            // TODO: Handle the case of no Gbuffer material
            // TODO: I comment the assert here because m_DeferredMaterial for whatever reasons contain the correct class but with a "null" in the name instead of the real name and then trigger the assert
            // whereas it work. Don't know what is happening, DebugDisplay use the same code and name is correct there.
            // Debug.Assert(m_DeferredMaterial != null);

            m_CameraColorBuffer                = HDShaderIDs._CameraColorTexture;
            m_CameraColorBufferRT              = new RenderTargetIdentifier(m_CameraColorBuffer);
            m_CameraSssDiffuseLightingBuffer   = HDShaderIDs._CameraSssDiffuseLightingBuffer;
            m_CameraSssDiffuseLightingBufferRT = new RenderTargetIdentifier(m_CameraSssDiffuseLightingBuffer);
            m_CameraFilteringBuffer            = HDShaderIDs._CameraFilteringBuffer;
            m_CameraFilteringBufferRT          = new RenderTargetIdentifier(m_CameraFilteringBuffer);

            CreateSssMaterials(sssSettings.useDisneySSS);

            m_CopyStencilForSplitLighting   = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/CopyStencilBuffer");
            m_CopyStencilForSplitLighting.EnableKeyword("EXPORT_HTILE");
            m_CopyStencilForSplitLighting.SetInt(HDShaderIDs._StencilRef, (int)StencilLightingUsage.SplitLighting);
            m_CopyStencilForRegularLighting = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/CopyStencilBuffer");
            m_CopyStencilForRegularLighting.DisableKeyword("EXPORT_HTILE");
            m_CopyStencilForRegularLighting.SetInt(HDShaderIDs._StencilRef, (int)StencilLightingUsage.RegularLighting);
            m_CameraMotionVectorsMaterial   = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/CameraMotionVectors");

            InitializeDebugMaterials();

            // Init Gbuffer description
            m_gbufferManager.gbufferCount = m_DeferredMaterial.GetMaterialGBufferCount();
            RenderTextureFormat[] RTFormat;
            RenderTextureReadWrite[] RTReadWrite;
            m_DeferredMaterial.GetMaterialGBufferDescription(out RTFormat, out RTReadWrite);

            for (int gbufferIndex = 0; gbufferIndex < m_gbufferManager.gbufferCount; ++gbufferIndex)
            {
                m_gbufferManager.SetBufferDescription(gbufferIndex, "_GBufferTexture" + gbufferIndex, RTFormat[gbufferIndex], RTReadWrite[gbufferIndex]);
            }

            m_VelocityBuffer = HDShaderIDs._VelocityTexture;
            if (ShaderConfig.s_VelocityInGbuffer == 1)
            {
                // If velocity is in GBuffer then it is in the last RT. Assign a different name to it.
                m_gbufferManager.SetBufferDescription(m_gbufferManager.gbufferCount, "_VelocityTexture", Builtin.GetVelocityBufferFormat(), Builtin.GetVelocityBufferReadWrite());
                m_gbufferManager.gbufferCount++;
            }
            m_VelocityBufferRT = new RenderTargetIdentifier(m_VelocityBuffer);

            m_DistortionBuffer = HDShaderIDs._DistortionTexture;
            m_DistortionBufferRT = new RenderTargetIdentifier(m_DistortionBuffer);

            m_MaterialList.ForEach(material => material.Build(asset.renderPipelineResources));

            m_LightLoop.Build(asset.renderPipelineResources, asset.tileSettings, asset.textureSettings, asset.shadowInitParams, m_ShadowSettings);

            m_SkyManager.Build(asset.renderPipelineResources);
            m_SkyManager.skySettings = skySettingsToUse;

            m_PostProcessContext = new PostProcessRenderContext();
            m_SsaoEffect = new ScreenSpaceAmbientOcclusionEffect();
            m_SsaoEffect.Build(asset.renderPipelineResources);

            m_DebugDisplaySettings.RegisterDebug();
            m_DebugFullScreenTempRT = HDShaderIDs._DebugFullScreenTexture;
        }

        void InitializeDebugMaterials()
        {
            m_DebugViewMaterialGBuffer = Utilities.CreateEngineMaterial(m_Asset.renderPipelineResources.debugViewMaterialGBufferShader);
            m_DebugDisplayLatlong = Utilities.CreateEngineMaterial(m_Asset.renderPipelineResources.debugDisplayLatlongShader);
            m_DebugFullScreen = Utilities.CreateEngineMaterial(m_Asset.renderPipelineResources.debugFullScreenShader);
        }

        public void CreateSssMaterials(bool useDisneySSS)
        {
            m_SubsurfaceScatteringKernel = m_SubsurfaceScatteringCS.FindKernel("SubsurfaceScattering");

            Utilities.Destroy(m_CombineLightingPass);
            m_CombineLightingPass = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/CombineLighting");

            // Old SSS Model >>>
            Utilities.Destroy(m_SssVerticalFilterPass);
            m_SssVerticalFilterPass = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/SubsurfaceScattering");
            m_SssVerticalFilterPass.DisableKeyword("SSS_FILTER_HORIZONTAL_AND_COMBINE");
            m_SssVerticalFilterPass.SetFloat(HDShaderIDs._DstBlend, (float)BlendMode.Zero);

            Utilities.Destroy(m_SssHorizontalFilterAndCombinePass);
            m_SssHorizontalFilterAndCombinePass = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/SubsurfaceScattering");
            m_SssHorizontalFilterAndCombinePass.EnableKeyword("SSS_FILTER_HORIZONTAL_AND_COMBINE");
            m_SssHorizontalFilterAndCombinePass.SetFloat(HDShaderIDs._DstBlend, (float)BlendMode.One);
            // <<< Old SSS Model
        }

        public void OnSceneLoad()
        {
            // Recreate the textures which went NULL
            m_MaterialList.ForEach(material => material.Build(m_Asset.renderPipelineResources));
        }

        public override void Dispose()
        {
            base.Dispose();

            m_LightLoop.Cleanup();

            m_MaterialList.ForEach(material => material.Cleanup());

            Utilities.Destroy(m_DebugViewMaterialGBuffer);
            Utilities.Destroy(m_DebugDisplayLatlong);

            m_SkyManager.Cleanup();

            m_SsaoEffect.Cleanup();

#if UNITY_EDITOR
            SupportedRenderingFeatures.active = SupportedRenderingFeatures.Default;
#endif
        }

#if UNITY_EDITOR
        private static readonly SupportedRenderingFeatures s_NeededFeatures = new SupportedRenderingFeatures()
        {
            reflectionProbe = SupportedRenderingFeatures.ReflectionProbe.Rotation
        };
#endif

        void CreateDepthStencilBuffer(Camera camera)
        {
            if (m_CameraDepthStencilBuffer != null)
            {
                m_CameraDepthStencilBuffer.Release();
            }

            m_CameraDepthStencilBuffer = new RenderTexture(camera.pixelWidth, camera.pixelHeight, 24, RenderTextureFormat.Depth);
            m_CameraDepthStencilBuffer.filterMode = FilterMode.Point;
            m_CameraDepthStencilBuffer.Create();
            m_CameraDepthStencilBufferRT = new RenderTargetIdentifier(m_CameraDepthStencilBuffer);

            if (NeedDepthBufferCopy())
            {
                if (m_CameraDepthBufferCopy != null)
                {
                    m_CameraDepthBufferCopy.Release();
                }
                m_CameraDepthBufferCopy = new RenderTexture(camera.pixelWidth, camera.pixelHeight, 24, RenderTextureFormat.Depth);
                m_CameraDepthBufferCopy.filterMode = FilterMode.Point;
                m_CameraDepthBufferCopy.Create();
                m_CameraDepthBufferCopyRT = new RenderTargetIdentifier(m_CameraDepthBufferCopy);
            }

            if (NeedStencilBufferCopy())
            {
                if (m_CameraStencilBufferCopy != null)
                {
                    m_CameraStencilBufferCopy.Release();
                }
                m_CameraStencilBufferCopy = new RenderTexture(camera.pixelWidth, camera.pixelHeight, 0, RenderTextureFormat.R8, RenderTextureReadWrite.Linear); // DXGI_FORMAT_R8_UINT is not supported by Unity
                m_CameraStencilBufferCopy.filterMode = FilterMode.Point;
                m_CameraStencilBufferCopy.Create();
                m_CameraStencilBufferCopyRT = new RenderTargetIdentifier(m_CameraStencilBufferCopy);
            }

            if (NeedHTileCopy())
            {
                if (m_HTile!= null)
                {
                    m_HTile.Release();
                }
                // We use 8x8 tiles in order to match the native GCN HTile as closely as possible.
                m_HTile = new RenderTexture((camera.pixelWidth + 7) / 8, (camera.pixelHeight + 7) / 8, 0, RenderTextureFormat.R8, RenderTextureReadWrite.Linear); // DXGI_FORMAT_R8_UINT is not supported by Unity
                m_HTile.filterMode = FilterMode.Point;
                m_HTile.enableRandomWrite = true;
                m_HTile.Create();
                m_HTileRT = new RenderTargetIdentifier(m_HTile);
            }
        }

        void Resize(Camera camera)
        {
            // TODO: Detect if renderdoc just load and force a resize in this case, as often renderdoc require to realloc resource.

            // TODO: This is the wrong way to handle resize/allocation. We can have several different camera here, mean that the loop on camera will allocate and deallocate
            // the below buffer which is bad. Best is to have a set of buffer for each camera that is persistent and reallocate resource if need
            // For now consider we have only one camera that go to this code, the main one.
            m_SkyManager.skySettings = skySettingsToUse;
            m_SkyManager.Resize(camera.nearClipPlane, camera.farClipPlane); // TODO: Also a bad naming, here we just want to realloc texture if skyparameters change (useful for lookdev)

            bool resolutionChanged = camera.pixelWidth != m_CurrentWidth || camera.pixelHeight != m_CurrentHeight;

            if (resolutionChanged || m_CameraDepthStencilBuffer == null)
            {
                CreateDepthStencilBuffer(camera);
            }

            if (resolutionChanged || m_LightLoop.NeedResize())
            {
                if (m_CurrentWidth > 0 && m_CurrentHeight > 0)
                {
                    m_LightLoop.ReleaseResolutionDependentBuffers();
                }

                m_LightLoop.AllocResolutionDependentBuffers(camera.pixelWidth, camera.pixelHeight);
            }

            if (resolutionChanged && m_VolumetricLightingEnabled)
            {
                CreateVolumetricLightingBuffers(camera.pixelWidth, camera.pixelHeight);
            }

            // update recorded window resolution
            m_CurrentWidth = camera.pixelWidth;
            m_CurrentHeight = camera.pixelHeight;
        }

        public void PushGlobalParams(HDCamera hdCamera, CommandBuffer cmd, SubsurfaceScatteringSettings sssParameters)
        {
            using (new Utilities.ProfilingSample("Push Global Parameters", cmd))
            {
                hdCamera.SetupGlobalParams(cmd);

                // TODO: cmd.SetGlobalInt() does not exist, so we are forced to use Shader.SetGlobalInt() instead.

                if (m_SkyManager.IsSkyValid())
                {
                    m_SkyManager.SetGlobalSkyTexture();
                    Shader.SetGlobalInt(HDShaderIDs._EnvLightSkyEnabled, 1);
                }
                else
                {
                    Shader.SetGlobalInt(HDShaderIDs._EnvLightSkyEnabled, 0);
                }

                // Broadcast SSS parameters to all shaders.
                Shader.SetGlobalInt(     HDShaderIDs._EnableSSSAndTransmission,   m_DebugDisplaySettings.renderingDebugSettings.enableSSSAndTransmission ? 1 : 0);
                Shader.SetGlobalInt(     HDShaderIDs._TexturingModeFlags,    (int)sssParameters.texturingModeFlags);
                Shader.SetGlobalInt(     HDShaderIDs._TransmissionFlags,     (int)sssParameters.transmissionFlags);
                Shader.SetGlobalInt(     HDShaderIDs._UseDisneySSS,               sssParameters.useDisneySSS ? 1 : 0);
                cmd.SetGlobalVectorArray(HDShaderIDs._ThicknessRemaps,            sssParameters.thicknessRemaps);
                cmd.SetGlobalVectorArray(HDShaderIDs._ShapeParams,                sssParameters.shapeParams);
                cmd.SetGlobalVectorArray(HDShaderIDs._HalfRcpVariancesAndWeights, sssParameters.halfRcpVariancesAndWeights);
                cmd.SetGlobalVectorArray(HDShaderIDs._TransmissionTints,          sssParameters.transmissionTints);

                SetGlobalVolumeProperties(m_VolumetricLightingEnabled, cmd);
            }
        }

        bool NeedDepthBufferCopy()
        {
            // For now we consider only PS4 to be able to read from a bound depth buffer. Need to test/implement for other platforms.
            return SystemInfo.graphicsDeviceType != GraphicsDeviceType.PlayStation4;
        }

        bool NeedStencilBufferCopy()
        {
            // Currently, Unity does not offer a way to bind the stencil buffer as a texture in a compute shader.
            // Therefore, it's manually copied using a pixel shader.
            return m_DebugDisplaySettings.renderingDebugSettings.enableSSSAndTransmission || LightLoop.GetFeatureVariantsEnabled(m_Asset.tileSettings);
        }

        bool NeedHTileCopy()
        {
            // Currently, Unity does not offer a way to access the GCN HTile even on PS4 and Xbox One.
            // Therefore, it's computed in a pixel shader, and optimized to only contain the SSS bit.
            return m_DebugDisplaySettings.renderingDebugSettings.enableSSSAndTransmission;
        }

        RenderTargetIdentifier GetDepthTexture()
        {
            return NeedDepthBufferCopy() ? m_CameraDepthBufferCopy : m_CameraDepthStencilBuffer;
        }

        RenderTargetIdentifier GetStencilTexture()
        {
            return NeedStencilBufferCopy() ? m_CameraStencilBufferCopyRT : m_CameraDepthStencilBufferRT;
        }

        RenderTargetIdentifier GetHTile()
        {
            // Currently, Unity does not offer a way to access the GCN HTile.
            return m_HTileRT;
        }

        private void CopyDepthBufferIfNeeded(CommandBuffer cmd)
        {
            using (new Utilities.ProfilingSample(NeedDepthBufferCopy() ? "Copy DepthBuffer" : "Set DepthBuffer", cmd))
            {
                if (NeedDepthBufferCopy())
                {
                    using (new Utilities.ProfilingSample("Copy depth-stencil buffer", cmd))
                    {
                        cmd.CopyTexture(m_CameraDepthStencilBufferRT, m_CameraDepthBufferCopyRT);
                    }
                }

                cmd.SetGlobalTexture(HDShaderIDs._MainDepthTexture, GetDepthTexture());
            }
        }

        private void PrepareAndBindStencilTexture(CommandBuffer cmd)
        {
            if (NeedStencilBufferCopy())
            {
                using (new Utilities.ProfilingSample("Copy StencilBuffer", cmd))
                {
                    cmd.SetRandomWriteTarget(1, GetHTile());
                    // Our method of exporting the stencil requires one pass per unique stencil value.
                    Utilities.DrawFullScreen(cmd, m_CopyStencilForSplitLighting,   m_CameraStencilBufferCopyRT, m_CameraDepthStencilBufferRT);
                    Utilities.DrawFullScreen(cmd, m_CopyStencilForRegularLighting, m_CameraStencilBufferCopyRT, m_CameraDepthStencilBufferRT);
                    cmd.ClearRandomWriteTargets();
                }
            }

            cmd.SetGlobalTexture(HDShaderIDs._HTile, GetHTile());
            cmd.SetGlobalTexture(HDShaderIDs._StencilTexture, GetStencilTexture());
        }

        public void UpdateCommonSettings()
        {
            var commonSettings = commonSettingsToUse;

            m_ShadowSettings.maxShadowDistance = commonSettings.shadowMaxDistance;
            m_ShadowSettings.directionalLightNearPlaneOffset = commonSettings.shadowNearPlaneOffset;
        }

        CullResults m_CullResults;
        public override void Render(ScriptableRenderContext renderContext, Camera[] cameras)
        {
            base.Render(renderContext, cameras);

#if UNITY_EDITOR
            SupportedRenderingFeatures.active = s_NeededFeatures;
#endif

            if (m_FrameCount != Time.frameCount)
            {
                HDCamera.CleanUnused();
                m_FrameCount = Time.frameCount;
            }

            GraphicsSettings.lightsUseLinearIntensity = true;
            GraphicsSettings.lightsUseColorTemperature = true;

            // This is the main command buffer used for the frame.
            CommandBuffer cmd = CommandBufferPool.Get("");

            m_MaterialList.ForEach(material => material.RenderInit(cmd));

            // Do anything we need to do upon a new frame.
            m_LightLoop.NewFrame();

            ApplyDebugDisplaySettings();
            UpdateCommonSettings();

            // Set Frame constant buffer
            // TODO...

            // we only want to render one camera for now
            // select the most main camera!

            Camera camera = null;
            foreach (var cam in cameras)
            {
                if (cam == Camera.main)
                {
                    camera = cam;
                    break;

                }
            }

            if (camera == null && cameras.Length > 0)
                camera = cameras[0];

            if (camera == null)
            {
                renderContext.Submit();
                return;
            }

            // Set camera constant buffer
            // TODO...

            ScriptableCullingParameters cullingParams;
            if (!CullResults.GetCullingParameters(camera, out cullingParams))
            {
                renderContext.Submit();
                return;
            }

            m_LightLoop.UpdateCullingParameters( ref cullingParams );
          
            // emit scene view UI
            if (camera.cameraType == CameraType.SceneView)
                ScriptableRenderContext.EmitWorldGeometryForSceneView(camera);

            CullResults.Cull(ref cullingParams, renderContext,ref m_CullResults);

            Resize(camera);

            renderContext.SetupCameraProperties(camera);

            var postProcessLayer = camera.GetComponent<PostProcessLayer>();
            HDCamera hdCamera = HDCamera.Get(camera, postProcessLayer);
            PushGlobalParams(hdCamera, cmd, m_Asset.sssSettings);

            // TODO: Find a correct place to bind these material textures
            // We have to bind the material specific global parameters in this mode
            m_MaterialList.ForEach(material => material.Bind());

            var additionalCameraData = camera.GetComponent<HDAdditionalCameraData>();
            if (additionalCameraData && additionalCameraData.renderingPath == RenderingPathHDRP.Unlit)
            {
                // TODO: Add another path dedicated to planar reflection / real time cubemap that implement simpler lighting
                string passName = "Forward"; // It is up to the users to only send unlit object for this camera path

                using (new Utilities.ProfilingSample(passName, cmd))
                {
                    Utilities.SetRenderTarget(cmd, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT, ClearFlag.ClearColor | ClearFlag.ClearDepth);
                    RenderOpaqueRenderList(m_CullResults, camera, renderContext, cmd, passName);
                    RenderTransparentRenderList(m_CullResults, camera, renderContext, cmd, passName);
                }

                renderContext.ExecuteCommandBuffer(cmd);
                CommandBufferPool.Release(cmd);
                renderContext.Submit();
                return;
            }

            InitAndClearBuffer(hdCamera, cmd);

            RenderDepthPrepass(m_CullResults, camera, renderContext, cmd);

            // Forward opaque with deferred/cluster tile require that we fill the depth buffer
            // correctly to build the light list.
            RenderForwardOnlyOpaqueDepthPrepass(m_CullResults, camera, renderContext, cmd);
            RenderGBuffer(m_CullResults, camera, renderContext, cmd);

            // If full forward rendering, we did not do any rendering yet, so don't need to copy the buffer.
            // If Deferred then the depth buffer is full (regular GBuffer + ForwardOnly depth prepass are done so we can copy it safely.
            if (!m_Asset.renderingSettings.useForwardRenderingOnly)
            {
                CopyDepthBufferIfNeeded(cmd);
            }

            // Required for the SSS and the shader feature classification pass.
            PrepareAndBindStencilTexture(cmd);

            if (m_DebugDisplaySettings.IsDebugMaterialDisplayEnabled())
            {
                RenderDebugViewMaterial(m_CullResults, hdCamera, renderContext, cmd);
            }
            else
            {
                using (new Utilities.ProfilingSample("Build Light list and render shadows", cmd))
                {
                    // TODO: Everything here (SSAO, Shadow, Build light list, material and light classification can be parallelize with Async compute)
                    m_SsaoEffect.Render(ssaoSettingsToUse, this, hdCamera, renderContext, cmd, m_Asset.renderingSettings.useForwardRenderingOnly);
                    m_LightLoop.PrepareLightsForGPU(m_ShadowSettings, m_CullResults, camera);
                    m_LightLoop.RenderShadows(renderContext, cmd, m_CullResults);
                    renderContext.SetupCameraProperties(camera); // Need to recall SetupCameraProperties after m_ShadowPass.Render
                    m_LightLoop.BuildGPULightLists(camera, cmd, m_CameraDepthStencilBufferRT, GetStencilTexture());
                }

                // Caution: We require sun light here as some sky use the sun light to render, mean UpdateSkyEnvironment
                // must be call after BuildGPULightLists.
                // TODO: Try to arrange code so we can trigger this call earlier and use async compute here to run sky convolution during other passes (once we move convolution shader to compute).
                UpdateSkyEnvironment(hdCamera, cmd);

                RenderDeferredLighting(hdCamera, cmd);

                // We compute subsurface scattering here. Therefore, no objects rendered afterwards will exhibit SSS.
                // Currently, there is no efficient way to switch between SRT and MRT for the forward pass;
                // therefore, forward-rendered objects do not output split lighting required for the SSS pass.
                SubsurfaceScatteringPass(hdCamera, cmd, m_Asset.sssSettings);

                // For opaque forward we have split rendering in two categories
                // Material that are always forward and material that can be deferred or forward depends on render pipeline options (like switch to rendering forward only mode)
                // Material that are always forward are unlit and complex (Like Hair) and don't require sorting, so it is ok to split them.
                RenderForward(m_CullResults, camera, renderContext, cmd, true); // Render deferred or forward opaque
                RenderForwardOnlyOpaque(m_CullResults, camera, renderContext, cmd);

                RenderLightingDebug(hdCamera, cmd, m_CameraColorBufferRT, m_DebugDisplaySettings);

                // If full forward rendering, we did just rendered everything, so we can copy the depth buffer
                // If Deferred nothing needs copying anymore.
                if (m_Asset.renderingSettings.useForwardRenderingOnly)
                {
                    CopyDepthBufferIfNeeded(cmd);
                }

                RenderSky(hdCamera, cmd);

                // Render all type of transparent forward (unlit, lit, complex (hair...)) to keep the sorting between transparent objects.
                RenderForward(m_CullResults, camera, renderContext, cmd, false);

                // Render fog.
                VolumetricLightingPass(cmd, hdCamera);

                PushFullScreenDebugTexture(cmd, m_CameraColorBuffer, camera, renderContext, FullScreenDebugMode.NanTracker);

                // Planar and real time cubemap doesn't need post process and render in FP16
                if (camera.cameraType == CameraType.Reflection)
                {
                    using (new Utilities.ProfilingSample("Blit to final RT", cmd))
                    {
                        // Simple blit
                        cmd.Blit(m_CameraColorBufferRT, BuiltinRenderTextureType.CameraTarget);
                    }

                }
                else
                {
                    RenderVelocity(m_CullResults, hdCamera, renderContext, cmd); // Note we may have to render velocity earlier if we do temporalAO, temporal volumetric etc... Mean we will not take into account forward opaque in case of deferred rendering ?

                    // TODO: Check with VFX team.
                    // Rendering distortion here have off course lot of artifact.
                    // But resolving at each objects that write in distortion is not possible (need to sort transparent, render those that do not distort, then resolve, then etc...)
                    // Instead we chose to apply distortion at the end after we cumulate distortion vector and desired blurriness. This
                    RenderDistortion(m_CullResults, camera, renderContext, cmd);

                    RenderPostProcesses(camera, cmd, postProcessLayer);
                }
            }

            RenderDebug(hdCamera, cmd);

            // bind depth surface for editor grid/gizmo/selection rendering
            if (camera.cameraType == CameraType.SceneView)
            {
                cmd.SetRenderTarget(BuiltinRenderTextureType.CameraTarget, m_CameraDepthStencilBufferRT);
            }

            renderContext.ExecuteCommandBuffer(cmd);
            CommandBufferPool.Release(cmd);
            renderContext.Submit();
        }

        private static Material m_ErrorMaterial;
        private static Material errorMaterial
        {
            get
            {
                if (m_ErrorMaterial == null)
                    m_ErrorMaterial = new Material(Shader.Find("Hidden/InternalErrorShader"));
                return m_ErrorMaterial;
            }
        }

        void RenderOpaqueRenderList(CullResults cull, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd, string passName, RendererConfiguration rendererConfiguration = 0)
        {
            if (!m_DebugDisplaySettings.renderingDebugSettings.displayOpaqueObjects)
                return;

            // This is done here because DrawRenderers API lives outside command buffers so we need to make call this before doing any DrawRenders
            renderContext.ExecuteCommandBuffer(cmd);
            cmd.Clear();

            var drawSettings = new DrawRendererSettings(camera, new ShaderPassName(passName))
            {
                rendererConfiguration = rendererConfiguration,
                sorting = { flags = SortFlags.CommonOpaque }
            };
            drawSettings.SetShaderPassName(1, new ShaderPassName("SRPDefaultUnlit"));
            var filterSettings = new FilterRenderersSettings(true) {renderQueueRange = RenderQueueRange.opaque};
            renderContext.DrawRenderers(cull.visibleRenderers, ref drawSettings, filterSettings);

#if UNITY_EDITOR
            // in editor draw invalid things with error material
            ConfigureErrorDraw(ref drawSettings);
            renderContext.DrawRenderers(cull.visibleRenderers, ref drawSettings, filterSettings);
#endif
        }

        void RenderTransparentRenderList(CullResults cull, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd, string passName, RendererConfiguration rendererConfiguration = 0)
        {
            if (!m_DebugDisplaySettings.renderingDebugSettings.displayTransparentObjects)
                return;

            // This is done here because DrawRenderers API lives outside command buffers so we need to make call this before doing any DrawRenders
            renderContext.ExecuteCommandBuffer(cmd);
            cmd.Clear();

            var drawSettings = new DrawRendererSettings(camera, new ShaderPassName(passName))
            {
                rendererConfiguration = rendererConfiguration,
                sorting = { flags = SortFlags.CommonTransparent }
            };
            var filterSettings = new FilterRenderersSettings(true) {renderQueueRange = RenderQueueRange.transparent};
            renderContext.DrawRenderers(cull.visibleRenderers, ref drawSettings, filterSettings);

#if UNITY_EDITOR
            // in editor draw invalid things with error material
            ConfigureErrorDraw(ref drawSettings);
            renderContext.DrawRenderers(cull.visibleRenderers, ref drawSettings, filterSettings);
#endif
        }

        private static void ConfigureErrorDraw(ref DrawRendererSettings drawSettings)
        {
            drawSettings.SetShaderPassName(0, new ShaderPassName("Always"));
            drawSettings.SetShaderPassName(1, new ShaderPassName("ForwardBase"));
            drawSettings.SetShaderPassName(2, new ShaderPassName("Deferred"));
            drawSettings.SetShaderPassName(3, new ShaderPassName("PrepassBase"));
            drawSettings.SetShaderPassName(4, new ShaderPassName("Vertex"));
            drawSettings.SetShaderPassName(5, new ShaderPassName("VertexLMRGBM"));
            drawSettings.SetShaderPassName(6, new ShaderPassName("VertexLM"));
            drawSettings.SetOverrideMaterial(errorMaterial, 0);
        }

        void RenderDepthPrepass(CullResults cull, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
           if (!m_Asset.renderingSettings.useDepthPrepass)
                return;

            using (new Utilities.ProfilingSample("Depth Prepass", cmd))
            {
                // TODO: Must do opaque then alpha masked for performance!
                // TODO: front to back for opaque and by material for opaque tested when we split in two
                Utilities.SetRenderTarget(cmd, m_CameraDepthStencilBufferRT);
                RenderOpaqueRenderList(cull, camera, renderContext, cmd, "DepthOnly");
            }
        }

        void RenderGBuffer(CullResults cull, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
            if (m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
                return;

            string passName = m_DebugDisplaySettings.IsDebugDisplayEnabled() ? "GBufferDebugDisplay" : "GBuffer";

            using (new Utilities.ProfilingSample(passName, cmd))
            {
                // setup GBuffer for rendering
                Utilities.SetRenderTarget(cmd, m_gbufferManager.GetGBuffers(), m_CameraDepthStencilBufferRT);
                // render opaque objects into GBuffer
                RenderOpaqueRenderList(cull, camera, renderContext, cmd, passName, Utilities.kRendererConfigurationBakedLighting);
            }
        }

        // This pass is use in case of forward opaque and deferred rendering. We need to render forward objects before tile lighting pass
        void RenderForwardOnlyOpaqueDepthPrepass(CullResults cull, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
            // If we are forward only we don't need to render ForwardOnlyOpaqueDepthOnly object
            // But in case we request a prepass we render it
            if (m_Asset.renderingSettings.ShouldUseForwardRenderingOnly() && !m_Asset.renderingSettings.useDepthPrepass)
                return;

            using (new Utilities.ProfilingSample("Forward opaque depth", cmd))
            {
                Utilities.SetRenderTarget(cmd, m_CameraDepthStencilBufferRT);
                RenderOpaqueRenderList(cull, camera, renderContext, cmd, "ForwardOnlyOpaqueDepthOnly");
            }
        }

        void RenderDebugViewMaterial(CullResults cull, HDCamera hdCamera, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
            using (new Utilities.ProfilingSample("DisplayDebug ViewMaterial", cmd))
            {
                if(m_DebugDisplaySettings.materialDebugSettings.IsDebugGBufferEnabled() && !m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
                {
                    using (new Utilities.ProfilingSample("DebugViewMaterialGBuffer", cmd))
                    {
                        Utilities.DrawFullScreen(cmd, m_DebugViewMaterialGBuffer, m_CameraColorBufferRT);
                    }
                }
                else
                {
                    Utilities.SetRenderTarget(cmd, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT, Utilities.kClearAll, Color.black);
                    // Render Opaque forward
                    RenderOpaqueRenderList(cull, hdCamera.camera, renderContext, cmd, "ForwardDisplayDebug", Utilities.kRendererConfigurationBakedLighting);

                    // Render forward transparent
                    RenderTransparentRenderList(cull, hdCamera.camera, renderContext, cmd, "ForwardDisplayDebug", Utilities.kRendererConfigurationBakedLighting);
                }
            }

            // Last blit
            {
                using (new Utilities.ProfilingSample("Blit DebugView Material Debug", cmd))
                {
                    cmd.Blit(m_CameraColorBufferRT, BuiltinRenderTextureType.CameraTarget);
                }
            }
        }

        void RenderDeferredLighting(HDCamera hdCamera, CommandBuffer cmd)
        {
            if (m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
            {
                return;
            }

            RenderTargetIdentifier[] colorRTs     = { m_CameraColorBufferRT, m_CameraSssDiffuseLightingBufferRT };
            RenderTargetIdentifier   depthTexture = GetDepthTexture();

            LightLoop.LightingPassOptions options = new LightLoop.LightingPassOptions();
            options.volumetricLightingEnabled = m_VolumetricLightingEnabled;

            if (m_DebugDisplaySettings.renderingDebugSettings.enableSSSAndTransmission)
            {
                // Output split lighting for materials asking for it (masked in the stencil buffer)
                options.outputSplitLighting = true;

                m_LightLoop.RenderDeferredLighting(hdCamera, cmd, m_DebugDisplaySettings, colorRTs, m_CameraDepthStencilBufferRT, depthTexture, options);
            }

            // Output combined lighting for all the other materials.
            options.outputSplitLighting = false;

            m_LightLoop.RenderDeferredLighting(hdCamera, cmd, m_DebugDisplaySettings, colorRTs, m_CameraDepthStencilBufferRT, depthTexture, options);
        }

        // Combines specular lighting and diffuse lighting with subsurface scattering.
        void SubsurfaceScatteringPass(HDCamera hdCamera, CommandBuffer cmd, SubsurfaceScatteringSettings sssParameters)
        {
            // Currently, forward-rendered objects do not output split lighting required for the SSS pass.
            if (!m_DebugDisplaySettings.renderingDebugSettings.enableSSSAndTransmission || m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
                return;

            using (new Utilities.ProfilingSample("Subsurface Scattering", cmd))
            {
                if (sssSettings.useDisneySSS)
                {
                    hdCamera.SetupComputeShader(m_SubsurfaceScatteringCS, cmd);

                    cmd.SetComputeIntParam(        m_SubsurfaceScatteringCS, HDShaderIDs._TexturingModeFlags, sssParameters.texturingModeFlags);
                    cmd.SetComputeVectorArrayParam(m_SubsurfaceScatteringCS, HDShaderIDs._WorldScales,        sssParameters.worldScales);
                    cmd.SetComputeVectorArrayParam(m_SubsurfaceScatteringCS, HDShaderIDs._FilterKernels,      sssParameters.filterKernels);
                    cmd.SetComputeVectorArrayParam(m_SubsurfaceScatteringCS, HDShaderIDs._ShapeParams,        sssParameters.shapeParams);

                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._GBufferTexture0,       m_gbufferManager.GetGBuffers()[0]);
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._GBufferTexture1,       m_gbufferManager.GetGBuffers()[1]);
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._GBufferTexture2,       m_gbufferManager.GetGBuffers()[2]);
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._GBufferTexture3,       m_gbufferManager.GetGBuffers()[3]);
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._DepthTexture,          GetDepthTexture());
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._StencilTexture,        GetStencilTexture());
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._HTile,                 GetHTile());
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._IrradianceSource,      m_CameraSssDiffuseLightingBufferRT);
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._CameraColorTexture,    m_CameraColorBufferRT);
                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._CameraFilteringBuffer, m_CameraFilteringBufferRT);

                    // Perform the SSS filtering pass which fills 'm_CameraFilteringBufferRT'.
                    cmd.DispatchCompute(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, ((int)hdCamera.screenSize.x + 15) / 16, ((int)hdCamera.screenSize.y + 15) / 16, 1);

                    cmd.SetGlobalTexture(HDShaderIDs._IrradianceSource, m_CameraFilteringBufferRT);  // Cannot set a RT on a material

                    // Combine diffuse and specular lighting into 'm_CameraColorBufferRT'.
                    Utilities.DrawFullScreen(cmd, m_CombineLightingPass, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT);
                }
                else
                {
                    cmd.SetGlobalTexture(HDShaderIDs._IrradianceSource, m_CameraSssDiffuseLightingBufferRT);  // Cannot set a RT on a material
                    m_SssVerticalFilterPass.SetVectorArray(HDShaderIDs._WorldScales,              sssParameters.worldScales);
                    m_SssVerticalFilterPass.SetVectorArray(HDShaderIDs._FilterKernelsBasic,       sssParameters.filterKernelsBasic);
                    m_SssVerticalFilterPass.SetVectorArray(HDShaderIDs._HalfRcpWeightedVariances, sssParameters.halfRcpWeightedVariances);
                    // Perform the vertical SSS filtering pass which fills 'm_CameraFilteringBufferRT'.
                    Utilities.DrawFullScreen(cmd, m_SssVerticalFilterPass, m_CameraFilteringBufferRT, m_CameraDepthStencilBufferRT);

                    cmd.SetGlobalTexture(HDShaderIDs._IrradianceSource, m_CameraFilteringBufferRT);  // Cannot set a RT on a material
                    m_SssHorizontalFilterAndCombinePass.SetVectorArray(HDShaderIDs._WorldScales,              sssParameters.worldScales);
                    m_SssHorizontalFilterAndCombinePass.SetVectorArray(HDShaderIDs._FilterKernelsBasic,       sssParameters.filterKernelsBasic);
                    m_SssHorizontalFilterAndCombinePass.SetVectorArray(HDShaderIDs._HalfRcpWeightedVariances, sssParameters.halfRcpWeightedVariances);
                    // Perform the horizontal SSS filtering pass, and combine diffuse and specular lighting into 'm_CameraColorBufferRT'.
                    Utilities.DrawFullScreen(cmd, m_SssHorizontalFilterAndCombinePass, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT);
                }
            }
        }

        void UpdateSkyEnvironment(HDCamera hdCamera, CommandBuffer cmd)
        {
            m_SkyManager.UpdateEnvironment(hdCamera,m_LightLoop.GetCurrentSunLight(), cmd);
        }

        void RenderSky(HDCamera hdCamera, CommandBuffer cmd)
        {
            m_SkyManager.RenderSky(hdCamera, m_LightLoop.GetCurrentSunLight(), m_CameraColorBufferRT, m_CameraDepthStencilBufferRT, cmd);
        }

        public Texture2D ExportSkyToTexture()
        {
            return m_SkyManager.ExportSkyToTexture();
        }

        void RenderLightingDebug(HDCamera camera, CommandBuffer cmd, RenderTargetIdentifier colorBuffer, DebugDisplaySettings debugDisplaySettings)
        {
            m_LightLoop.RenderLightingDebug(camera, cmd, colorBuffer, debugDisplaySettings);
        }

        void RenderForward(CullResults cullResults, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd, bool renderOpaque)
        {
            if (!m_Asset.renderingSettings.ShouldUseForwardRenderingOnly() && renderOpaque)
                return;

            string passName = m_DebugDisplaySettings.IsDebugDisplayEnabled() ? "ForwardDisplayDebug" : "Forward";

            using (new Utilities.ProfilingSample(passName, cmd))
            {
                Utilities.SetRenderTarget(cmd, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT);

                m_LightLoop.RenderForward(camera, cmd, renderOpaque);

                if (renderOpaque)
                {
                    RenderOpaqueRenderList(cullResults, camera, renderContext, cmd, passName, Utilities.kRendererConfigurationBakedLighting);
                }
                else
                {
                    RenderTransparentRenderList(cullResults, camera, renderContext, cmd, passName, Utilities.kRendererConfigurationBakedLighting);
                }
            }
        }

        // Render material that are forward opaque only (like eye), this include unlit material
        void RenderForwardOnlyOpaque(CullResults cullResults, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
            string passName = m_DebugDisplaySettings.IsDebugDisplayEnabled() ? "ForwardOnlyOpaqueDisplayDebug" : "ForwardOnlyOpaque";

            using (new Utilities.ProfilingSample(passName, cmd))
            {
                Utilities.SetRenderTarget(cmd, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT);

                m_LightLoop.RenderForward(camera, cmd, true);

                RenderOpaqueRenderList(cullResults, camera, renderContext, cmd, passName, Utilities.kRendererConfigurationBakedLighting);
            }
        }

        void RenderVelocity(CullResults cullResults, HDCamera hdcam, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
            using (new Utilities.ProfilingSample("Velocity", cmd))
            {
                // If opaque velocity have been render during GBuffer no need to render it here
                if ((ShaderConfig.s_VelocityInGbuffer == 1) || m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
                    return;

                // These flags are still required in SRP or the engine won't compute previous model matrices...
                // If the flag hasn't been set yet on this camera, motion vectors will skip a frame.
                hdcam.camera.depthTextureMode |= DepthTextureMode.MotionVectors | DepthTextureMode.Depth;

                int w = (int)hdcam.screenSize.x;
                int h = (int)hdcam.screenSize.y;

                m_CameraMotionVectorsMaterial.SetVector(HDShaderIDs._CameraPosDiff, hdcam.prevCameraPos - hdcam.cameraPos);

                cmd.GetTemporaryRT(m_VelocityBuffer, w, h, 0, FilterMode.Point, Builtin.GetVelocityBufferFormat(), Builtin.GetVelocityBufferReadWrite());
                Utilities.DrawFullScreen(cmd, m_CameraMotionVectorsMaterial, m_VelocityBufferRT, null, 0);
                cmd.SetRenderTarget(m_VelocityBufferRT, m_CameraDepthStencilBufferRT);

                RenderOpaqueRenderList(cullResults, hdcam.camera, renderContext, cmd, "MotionVectors", RendererConfiguration.PerObjectMotionVectors);

                PushFullScreenDebugTexture(cmd, m_VelocityBuffer, hdcam.camera, renderContext, FullScreenDebugMode.MotionVectors);
            }
        }

        void RenderDistortion(CullResults cullResults, Camera camera, ScriptableRenderContext renderContext, CommandBuffer cmd)
        {
            if (!m_DebugDisplaySettings.renderingDebugSettings.enableDistortion)
                return;

            using (new Utilities.ProfilingSample("Distortion", cmd))
            {
                int w = camera.pixelWidth;
                int h = camera.pixelHeight;

                cmd.GetTemporaryRT(m_DistortionBuffer, w, h, 0, FilterMode.Point, Builtin.GetDistortionBufferFormat(), Builtin.GetDistortionBufferReadWrite());
                cmd.SetRenderTarget(m_DistortionBufferRT, m_CameraDepthStencilBufferRT);
                cmd.ClearRenderTarget(false, true, Color.black); // TODO: can we avoid this clear for performance ?

                // Only transparent object can render distortion vectors
                RenderTransparentRenderList(cullResults, camera, renderContext, cmd, "DistortionVectors");
            }
        }

        void RenderPostProcesses(Camera camera, CommandBuffer cmd, PostProcessLayer layer)
        {
            using (new Utilities.ProfilingSample("Post-processing", cmd))
            {
                if (Utilities.IsPostProcessingActive(layer))
                {
                    cmd.SetGlobalTexture(HDShaderIDs._CameraDepthTexture, GetDepthTexture());
                    cmd.SetGlobalTexture(HDShaderIDs._CameraMotionVectorsTexture, m_VelocityBufferRT);

                    var context = m_PostProcessContext;
                    context.Reset();
                    context.source = m_CameraColorBufferRT;
                    context.destination = BuiltinRenderTextureType.CameraTarget;
                    context.command = cmd;
                    context.camera = camera;
                    context.sourceFormat = RenderTextureFormat.ARGBHalf;
                    context.flip = true;

                    layer.Render(context);
                }
                else
                {
                    cmd.Blit(m_CameraColorBufferRT, BuiltinRenderTextureType.CameraTarget);
                }
            }
        }

        public void ApplyDebugDisplaySettings()
        {
            m_ShadowSettings.enabled = m_DebugDisplaySettings.lightingDebugSettings.enableShadows;

            LightingDebugSettings lightingDebugSettings = m_DebugDisplaySettings.lightingDebugSettings;
            Vector4 debugAlbedo = new Vector4(lightingDebugSettings.debugLightingAlbedo.r, lightingDebugSettings.debugLightingAlbedo.g, lightingDebugSettings.debugLightingAlbedo.b, 0.0f);
            Vector4 debugSmoothness = new Vector4(lightingDebugSettings.overrideSmoothness ? 1.0f : 0.0f, lightingDebugSettings.overrideSmoothnessValue, 0.0f, 0.0f);

            Shader.SetGlobalInt(HDShaderIDs._DebugViewMaterial, (int)m_DebugDisplaySettings.GetDebugMaterialIndex());
            Shader.SetGlobalInt(HDShaderIDs._DebugLightingMode, (int)m_DebugDisplaySettings.GetDebugLightingMode());
            Shader.SetGlobalVector(HDShaderIDs._DebugLightingAlbedo, debugAlbedo);
            Shader.SetGlobalVector(HDShaderIDs._DebugLightingSmoothness, debugSmoothness);
        }

        public void PushFullScreenDebugTexture(CommandBuffer cb, int textureID, Camera camera, ScriptableRenderContext renderContext, FullScreenDebugMode debugMode)
        {
            if(debugMode == m_DebugDisplaySettings.fullScreenDebugMode)
            {
                m_FullScreenDebugPushed = true; // We need this flag because otherwise if no fullscreen debug is pushed, when we render the result in RenderDebug the temporary RT will not exist.
                cb.GetTemporaryRT(m_DebugFullScreenTempRT, camera.pixelWidth, camera.pixelHeight, 0, FilterMode.Point, RenderTextureFormat.ARGBHalf, RenderTextureReadWrite.Linear);
                cb.Blit(textureID, m_DebugFullScreenTempRT);
            }
        }

        void RenderDebug(HDCamera camera, CommandBuffer cmd)
        {
            // We don't want any overlay for these kind of rendering
            if (camera.camera.cameraType == CameraType.Reflection || camera.camera.cameraType == CameraType.Preview)
                return;

            using (new Utilities.ProfilingSample("Render Debug", cmd))
            {
                // We make sure the depth buffer is bound because we need it to write depth at near plane for overlays otherwise the editor grid end up visible in them.
                Utilities.SetRenderTarget(cmd, BuiltinRenderTextureType.CameraTarget, m_CameraDepthStencilBufferRT);

                // First render full screen debug texture
                if(m_DebugDisplaySettings.fullScreenDebugMode != FullScreenDebugMode.None && m_FullScreenDebugPushed)
                {
                    m_FullScreenDebugPushed = false;
                    cmd.SetGlobalTexture(HDShaderIDs._DebugFullScreenTexture, m_DebugFullScreenTempRT);
                    m_DebugFullScreen.SetFloat(HDShaderIDs._FullScreenDebugMode, (float)m_DebugDisplaySettings.fullScreenDebugMode);
                    Utilities.DrawFullScreen(cmd, m_DebugFullScreen, (RenderTargetIdentifier)BuiltinRenderTextureType.CameraTarget);
                }

                // Then overlays
                float x = 0;
                float overlayRatio = m_DebugDisplaySettings.debugOverlayRatio;
                float overlaySize = Math.Min(camera.camera.pixelHeight, camera.camera.pixelWidth) * overlayRatio;
                float y = camera.camera.pixelHeight - overlaySize;

                LightingDebugSettings lightingDebug = m_DebugDisplaySettings.lightingDebugSettings;

                if (lightingDebug.displaySkyReflection)
                {
                    Texture skyReflection = m_SkyManager.skyReflection;
                    m_SharedPropertyBlock.SetTexture(HDShaderIDs._InputCubemap, skyReflection);
                    m_SharedPropertyBlock.SetFloat(HDShaderIDs._Mipmap, lightingDebug.skyReflectionMipmap);
                    cmd.SetViewport(new Rect(x, y, overlaySize, overlaySize));
                    cmd.DrawProcedural(Matrix4x4.identity, m_DebugDisplayLatlong, 0, MeshTopology.Triangles, 3, 1, m_SharedPropertyBlock);
                    Utilities.NextOverlayCoord(ref x, ref y, overlaySize, overlaySize, camera.camera.pixelWidth);
                }

                m_LightLoop.RenderDebugOverlay(camera.camera, cmd, m_DebugDisplaySettings, ref x, ref y, overlaySize, camera.camera.pixelWidth);
            }
        }

        void InitAndClearBuffer(HDCamera camera, CommandBuffer cmd)
        {
            using (new Utilities.ProfilingSample("InitAndClearBuffer", cmd))
            {
                // We clear only the depth buffer, no need to clear the various color buffer as we overwrite them.
                // Clear depth/stencil and init buffers
                using (new Utilities.ProfilingSample("InitGBuffers and clear Depth/Stencil", cmd))
                {
                    // Init buffer
                    // With scriptable render loop we must allocate ourself depth and color buffer (We must be independent of backbuffer for now, hope to fix that later).
                    // Also we manage ourself the HDR format, here allocating fp16 directly.
                    // With scriptable render loop we can allocate temporary RT in a command buffer, they will not be release with ExecuteCommandBuffer
                    // These temporary surface are release automatically at the end of the scriptable render pipeline if not release explicitly
                    int w = camera.camera.pixelWidth;
                    int h = camera.camera.pixelHeight;

                    cmd.GetTemporaryRT(m_CameraColorBuffer,              w, h, 0, FilterMode.Point, RenderTextureFormat.ARGBHalf,       RenderTextureReadWrite.Linear, 1, true); // Enable UAV
                    cmd.GetTemporaryRT(m_CameraSssDiffuseLightingBuffer, w, h, 0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
                    cmd.GetTemporaryRT(m_CameraFilteringBuffer,          w, h, 0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV

                    if (!m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
                    {
                        m_gbufferManager.InitGBuffers(w, h, cmd);
                    }

                    Utilities.SetRenderTarget(cmd, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT, ClearFlag.ClearDepth);
                }

                // Clear the diffuse SSS lighting target
                using (new Utilities.ProfilingSample("Clear SSS diffuse target", cmd))
                {
                    Utilities.SetRenderTarget(cmd, m_CameraSssDiffuseLightingBufferRT, ClearFlag.ClearColor, Color.black);
                }

                // Old SSS Model >>>
                if (!sssSettings.useDisneySSS)
                {
                    // Clear the SSS filtering target
                    using (new Utilities.ProfilingSample("Clear SSS filtering target", cmd))
                    {
                        Utilities.SetRenderTarget(cmd, m_CameraFilteringBuffer, ClearFlag.ClearColor, Color.black);
                    }
                }
                // <<< Old SSS Model

                if (NeedStencilBufferCopy())
                {
                    using (new Utilities.ProfilingSample("Clear stencil texture", cmd))
                    {
                        Utilities.SetRenderTarget(cmd, m_CameraStencilBufferCopyRT, ClearFlag.ClearColor, Color.black);
                    }
                }

                if (NeedHTileCopy())
                {
                    using (new Utilities.ProfilingSample("Clear HTile", cmd))
                    {
                        Utilities.SetRenderTarget(cmd, m_HTileRT, ClearFlag.ClearColor, Color.black);
                    }
                }

                if (m_VolumetricLightingEnabled)
                {
                    ClearVolumetricLightingBuffers(cmd, camera.isFirstFrame);
                }

                // TEMP: As we are in development and have not all the setup pass we still clear the color in emissive buffer and gbuffer, but this will be removed later.

                // Clear the HDR target
                using (new Utilities.ProfilingSample("Clear HDR target", cmd))
                {
                    Utilities.SetRenderTarget(cmd, m_CameraColorBufferRT, m_CameraDepthStencilBufferRT, ClearFlag.ClearColor, Color.black);
                }

                // Clear GBuffers
                if (!m_Asset.renderingSettings.ShouldUseForwardRenderingOnly())
                {
                    using (new Utilities.ProfilingSample("Clear GBuffer", cmd))
                    {
                        Utilities.SetRenderTarget(cmd, m_gbufferManager.GetGBuffers(), m_CameraDepthStencilBufferRT, ClearFlag.ClearColor, Color.black);
                    }
                }
                // END TEMP
            }
        }
    }
}