From 60d6416e5f8200d5340f75d2655a1478b1472330 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Mon, 26 Mar 2018 23:32:07 +0200
Subject: [PATCH] [dxbc] Implemnted SV_ViewportArrayIndex for geometry shaders

Required by Final Fantasy XIV.
---
 src/dxbc/dxbc_compiler.cpp | 19 +++++++++++++++++++
 src/dxbc/dxbc_compiler.h   |  1 +
 2 files changed, 20 insertions(+)

diff --git a/src/dxbc/dxbc_compiler.cpp b/src/dxbc/dxbc_compiler.cpp
index 94f67d9d..cbe47837 100644
--- a/src/dxbc/dxbc_compiler.cpp
+++ b/src/dxbc/dxbc_compiler.cpp
@@ -5175,6 +5175,25 @@ namespace dxvk {
           DxbcRegMask(true, false, false, false));
       } break;
       
+      case DxbcSystemValue::ViewportId: {
+        if (m_gs.builtinViewportId == 0) {
+          m_gs.builtinViewportId = emitNewBuiltinVariable({
+            { DxbcScalarType::Uint32, 1, 0 },
+            spv::StorageClassOutput },
+            spv::BuiltInViewportIndex,
+            "gs_viewport_id");
+        }
+        
+        DxbcRegisterPointer ptr;
+        ptr.type.ctype   = DxbcScalarType::Uint32;
+        ptr.type.ccount  = 1;
+        ptr.id = m_gs.builtinViewportId;
+        
+        emitValueStore(
+          ptr, emitRegisterExtract(value, mask),
+          DxbcRegMask(true, false, false, false));
+      } break;
+      
       default:
         Logger::warn(str::format(
           "DxbcCompiler: Unhandled GS SV output: ", sv));
diff --git a/src/dxbc/dxbc_compiler.h b/src/dxbc/dxbc_compiler.h
index 6f50b37c..83145891 100644
--- a/src/dxbc/dxbc_compiler.h
+++ b/src/dxbc/dxbc_compiler.h
@@ -119,6 +119,7 @@ namespace dxvk {
     uint32_t              functionId          = 0;
     
     uint32_t builtinLayer         = 0;
+    uint32_t builtinViewportId    = 0;
   };