[Graphics]Adding mip level and slices to color and depth attachment for RG

This PR is related to the [URP-2105](https://jira.unity3d.com/browse/URP-2105) jira epic.
The purpose of this PR is to add missing functionality by adding mip level and slices to RG's  SetInputAttachment and SetRenderAttachment functions.

This PR also introduces helper functions for Copy and Blit as well as a test to ensure the newly added functionality and the helper functions work as expected.

There is also a fix for invalid texture description for imported textures

Author: Nzollner

Packages/com.unity.render-pipelines.core/Editor/RenderGraph/RenderGraphUtilsResourceStripper.cs

@@ -0,0 +1,12 @@
+using UnityEngine.Rendering;
+using UnityEngine.Rendering.RenderGraphModule.Util;
+
+namespace UnityEditor.Rendering.RenderGraphModule.Util
+{
+    class RenderGraphUtilsResourcesStripper : IRenderPipelineGraphicsSettingsStripper<RenderGraphUtilsResources>
+    {
+        public bool active => true;
+
+        public bool CanRemoveSettings(RenderGraphUtilsResources settings) => false;
+    }
+}

Packages/com.unity.render-pipelines.core/Editor/RenderGraph/RenderGraphUtilsResourceStripper.cs.meta

@@ -136,18 +136,18 @@ public ref ResourceReaderData ResourceReader(ResourceHandle h, int i)
         public NativeList<SubPassDescriptor> nativeSubPassData; //Tighty packed list of per nrp subpasses
 
         // resources can be added as fragment both as input and output so make sure not to add them twice (return true upon new addition)
-        public bool AddToFragmentList(ResourceHandle h, AccessFlags accessFlags, int listFirstIndex, int numItems)
+        public bool AddToFragmentList(TextureAccess access, int listFirstIndex, int numItems)
         {
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
-            if (h.type != RenderGraphResourceType.Texture) new Exception("Only textures can be used as a fragment attachment.");
+            if (access.textureHandle.handle.type != RenderGraphResourceType.Texture) new Exception("Only textures can be used as a fragment attachment.");
 #endif
             for (var i = listFirstIndex; i < listFirstIndex + numItems; ++i)
             {
                 ref var fragment = ref fragmentData.ElementAt(i);
-                if (fragment.resource.index == h.index)
+                if (fragment.resource.index == access.textureHandle.handle.index)
                 {
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
-                    if (fragment.resource.version != h.version)
+                    if (fragment.resource.version != access.textureHandle.handle.version)
                     {
                         //this would mean you're trying to attach say both v1 and v2 of a resource to the same pass as an attachment
                         //this is not allowed
@@ -164,8 +164,10 @@ public bool AddToFragmentList(ResourceHandle h, AccessFlags accessFlags, int lis
 
             fragmentData.Add(new PassFragmentData()
             {
-                resource = h,
-                accessFlags = accessFlags
+                resource = access.textureHandle.handle,
+                accessFlags = access.flags,
+                mipLevel = access.mipLevel,
+                depthSlice = access.depthSlice,
             });
             return true;
         }

Packages/com.unity.render-pipelines.core/Runtime/RenderGraph/Compiler/CompilerContextData.cs

@@ -175,26 +175,24 @@ void BuildGraph()
                         ctxPass.firstFragment = ctx.fragmentData.Length;
 
                         // Depth attachment is always at index 0
-                        if (inputPass.depthBuffer.handle.IsValid())
+                        if (inputPass.depthAccess.textureHandle.handle.IsValid())
                         {
                             ctxPass.fragmentInfoHasDepth = true;
 
-                            var resource = inputPass.depthBuffer.handle;
-                            if (ctx.AddToFragmentList(resource, inputPass.depthBufferAccessFlags, ctxPass.firstFragment, ctxPass.numFragments))
+                            if (ctx.AddToFragmentList(inputPass.depthAccess, ctxPass.firstFragment, ctxPass.numFragments))
                             {
-                                ctxPass.AddFragment(resource, ctx);
+                                ctxPass.AddFragment(inputPass.depthAccess.textureHandle.handle, ctx);
                             }
                         }
 
                         for (var ci = 0; ci < inputPass.colorBufferMaxIndex + 1; ++ci)
                         {
                             // Skip unused color slots
-                            if (!inputPass.colorBuffers[ci].handle.IsValid()) continue;
+                            if (!inputPass.colorBufferAccess[ci].textureHandle.handle.IsValid()) continue;
 
-                            var resource = inputPass.colorBuffers[ci].handle;
-                            if (ctx.AddToFragmentList(resource, inputPass.colorBufferAccessFlags[ci], ctxPass.firstFragment, ctxPass.numFragments))
+                            if (ctx.AddToFragmentList(inputPass.colorBufferAccess[ci], ctxPass.firstFragment, ctxPass.numFragments))
                             {
-                                ctxPass.AddFragment(resource, ctx);
+                                ctxPass.AddFragment(inputPass.colorBufferAccess[ci].textureHandle.handle, ctx);
                             }
                         }
 
@@ -203,14 +201,13 @@ void BuildGraph()
 
                         for (var ci = 0; ci < inputPass.fragmentInputMaxIndex + 1; ++ci)
                         {
-                            ref var currInpFragment = ref inputPass.fragmentInputs[ci].handle;
                             // Skip unused fragment input slots
-                            if (!currInpFragment.IsValid()) continue;
+                            if (!inputPass.fragmentInputAccess[ci].textureHandle.IsValid()) continue;
 
-                            var resource = inputPass.fragmentInputs[ci].handle;
-                            if (ctx.AddToFragmentList(resource, inputPass.fragmentInputAccessFlags[ci], ctxPass.firstFragmentInput, ctxPass.numFragmentInputs))
+                            var resource = inputPass.fragmentInputAccess[ci].textureHandle;
+                            if (ctx.AddToFragmentList(inputPass.fragmentInputAccess[ci], ctxPass.firstFragmentInput, ctxPass.numFragmentInputs))
                             {
-                                ctxPass.AddFragmentInput(resource, ctx);
+                                ctxPass.AddFragmentInput(inputPass.fragmentInputAccess[ci].textureHandle.handle, ctx);
                             }
                         }
 
@@ -885,6 +882,8 @@ void PrepareNativeRenderPass(ref NativePassData nativePass)
                     ref var currStoreAudit = ref nativePass.storeAudit[idx];
 #endif
                     currAttachment.handle = fragment.resource;
+                    currAttachment.mipLevel = fragment.mipLevel;
+                    currAttachment.depthSlice = fragment.depthSlice;
 
                     // Don't care by default
                     currAttachment.loadAction = UnityEngine.Rendering.RenderBufferLoadAction.DontCare;
@@ -1212,7 +1211,7 @@ internal unsafe void ExecuteBeginRenderPass(InternalRenderGraphContext rgContext
                         //but that is why we mark this as a hack and future work to fix.
                         //The proper (and planned) solution would be to move away from the render texture duality.
                         RenderTargetIdentifier rtidAllSlices = rtHandle;
-                        currBeginAttachment.loadStoreTarget = new RenderTargetIdentifier(rtidAllSlices, 0, CubemapFace.Unknown, -1);
+                        currBeginAttachment.loadStoreTarget = new RenderTargetIdentifier(rtidAllSlices, attachments[i].mipLevel, CubemapFace.Unknown, attachments[i].depthSlice);
 
                         if (attachments[i].storeAction == RenderBufferStoreAction.Resolve ||
                             attachments[i].storeAction == RenderBufferStoreAction.StoreAndResolve)
@@ -1231,7 +1230,7 @@ internal unsafe void ExecuteBeginRenderPass(InternalRenderGraphContext rgContext
                         currBeginAttachment.clearColor = Color.red;
                         currBeginAttachment.clearDepth = 1.0f;
                         currBeginAttachment.clearStencil = 0;
-                        var desc = resources.GetTextureResourceDesc(currAttachmentHandle);
+                        var desc = resources.GetTextureResourceDesc(currAttachmentHandle, true);
                         if (i == 0 && nativePass.hasDepth)
                         {
                             // TODO: There seems to be no clear depth specified ?!?!

Packages/com.unity.render-pipelines.core/Runtime/RenderGraph/Compiler/NativePassCompiler.cs

@@ -27,20 +27,24 @@ internal struct PassFragmentData
     {
         public ResourceHandle resource;
         public AccessFlags accessFlags;
+        public int mipLevel;
+        public int depthSlice;
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public override int GetHashCode()
         {
             var hash = resource.GetHashCode();
             hash = hash * 23 + accessFlags.GetHashCode();
+            hash = hash * 23 + mipLevel.GetHashCode();
+            hash = hash * 23 + depthSlice.GetHashCode();
             return hash;
         }
 
         public static bool EqualForMerge(PassFragmentData x, PassFragmentData y)
         {
             // We ignore the version for now we assume if one pass writes version x and the next y they can
             // be merged in the same native render pass
-            return x.resource.index == y.resource.index && x.accessFlags == y.accessFlags;
+            return x.resource.index == y.resource.index && x.accessFlags == y.accessFlags && x.mipLevel == y.mipLevel && x.depthSlice == y.depthSlice;
         }
     }
 
@@ -366,6 +370,8 @@ internal struct NativePassAttachment
         public UnityEngine.Rendering.RenderBufferLoadAction loadAction;
         public UnityEngine.Rendering.RenderBufferStoreAction storeAction;
         public bool memoryless;
+        public int mipLevel;
+        public int depthSlice;
     }
 
     internal enum LoadReason