From c630ece43a2cc5c8fda029b5154d575321de58e8 Mon Sep 17 00:00:00 2001
From: Qing Tao <55564570+VickyAtAZ@users.noreply.github.com>
Date: Fri, 28 May 2021 09:42:11 -0700
Subject: [PATCH] Add m_linearDepthTexture as input for transparent pass.

This is required by popcornfx and it doesn't add extra cost to the render pipeline.
---
 .../Feature/Common/Assets/Passes/LowEndPipeline.pass  |  7 +++++++
 .../Feature/Common/Assets/Passes/MainPipeline.pass    |  7 +++++++
 .../Feature/Common/Assets/Passes/Transparent.pass     |  6 ++++++
 .../Common/Assets/Passes/TransparentParent.pass       | 11 +++++++++++
 .../Atom/Features/PBR/TransparentPassSrg.azsli        |  1 +
 5 files changed, 32 insertions(+)

diff --git a/Gems/Atom/Feature/Common/Assets/Passes/LowEndPipeline.pass b/Gems/Atom/Feature/Common/Assets/Passes/LowEndPipeline.pass
index b19569fb9d..38a4524aa2 100644
--- a/Gems/Atom/Feature/Common/Assets/Passes/LowEndPipeline.pass
+++ b/Gems/Atom/Feature/Common/Assets/Passes/LowEndPipeline.pass
@@ -243,6 +243,13 @@
                                 "Attachment": "LightListRemapped"
                             }
                         },
+                        {
+                            "LocalSlot": "InputLinearDepth",
+                            "AttachmentRef": {
+                                "Pass": "DepthPrePass",
+                                "Attachment": "DepthLinear"
+                            }
+                        },
                         {
                             "LocalSlot": "DepthStencil",
                             "AttachmentRef": {
diff --git a/Gems/Atom/Feature/Common/Assets/Passes/MainPipeline.pass b/Gems/Atom/Feature/Common/Assets/Passes/MainPipeline.pass
index ee943f6d39..af7408b48c 100644
--- a/Gems/Atom/Feature/Common/Assets/Passes/MainPipeline.pass
+++ b/Gems/Atom/Feature/Common/Assets/Passes/MainPipeline.pass
@@ -251,6 +251,13 @@
                                 "Attachment": "LightListRemapped"
                             }
                         },
+                        {
+                            "LocalSlot": "InputLinearDepth",
+                            "AttachmentRef": {
+                                "Pass": "DepthPrePass",
+                                "Attachment": "DepthLinear"
+                            }
+                        },
                         {
                             "LocalSlot": "DepthStencil",
                             "AttachmentRef": {
diff --git a/Gems/Atom/Feature/Common/Assets/Passes/Transparent.pass b/Gems/Atom/Feature/Common/Assets/Passes/Transparent.pass
index 415aa2fec0..3bb184a1f8 100644
--- a/Gems/Atom/Feature/Common/Assets/Passes/Transparent.pass
+++ b/Gems/Atom/Feature/Common/Assets/Passes/Transparent.pass
@@ -67,6 +67,12 @@
                     "ShaderInputName": "m_lightListRemapped",
                     "ScopeAttachmentUsage": "Shader"
                 },
+                {
+                    "Name": "InputLinearDepth",
+                    "SlotType": "Input",
+                    "ShaderInputName": "m_linearDepthTexture",
+                    "ScopeAttachmentUsage": "Shader"
+                },
                 // Input/Outputs
                 {
                     "Name": "DepthStencil",
diff --git a/Gems/Atom/Feature/Common/Assets/Passes/TransparentParent.pass b/Gems/Atom/Feature/Common/Assets/Passes/TransparentParent.pass
index 32517484f3..b278f2bcb4 100644
--- a/Gems/Atom/Feature/Common/Assets/Passes/TransparentParent.pass
+++ b/Gems/Atom/Feature/Common/Assets/Passes/TransparentParent.pass
@@ -32,6 +32,10 @@
                     "Name": "LightListRemapped",
                     "SlotType": "Input"
                 },
+                {
+                    "Name": "InputLinearDepth",
+                    "SlotType": "Input"
+                },
                 // Input/Outputs...
                 {
                     "Name": "DepthStencil",
@@ -91,6 +95,13 @@
                                 "Attachment": "LightListRemapped"
                             }
                         },
+                        {
+                            "LocalSlot": "InputLinearDepth",
+                            "AttachmentRef": {
+                                "Pass": "Parent",
+                                "Attachment": "InputLinearDepth"
+                            }
+                        },
                         // Input/Outputs...
                         {
                             "LocalSlot": "DepthStencil",
diff --git a/Gems/Atom/Feature/Common/Assets/ShaderLib/Atom/Features/PBR/TransparentPassSrg.azsli b/Gems/Atom/Feature/Common/Assets/ShaderLib/Atom/Features/PBR/TransparentPassSrg.azsli
index 14cff21739..d9367f9d03 100644
--- a/Gems/Atom/Feature/Common/Assets/ShaderLib/Atom/Features/PBR/TransparentPassSrg.azsli
+++ b/Gems/Atom/Feature/Common/Assets/ShaderLib/Atom/Features/PBR/TransparentPassSrg.azsli
@@ -35,4 +35,5 @@ ShaderResourceGroup PassSrg : SRG_PerPass
     
     Texture2D<uint4> m_tileLightData;
     StructuredBuffer<uint> m_lightListRemapped;
+    Texture2D<float> m_linearDepthTexture;
 }