From c0bafdb37f1a50876db4904f0c069e821ab41d82 Mon Sep 17 00:00:00 2001
From: Skyth <19259897+blueskythlikesclouds@users.noreply.github.com>
Date: Wed, 16 Oct 2024 17:36:35 +0300
Subject: [PATCH] Implement svPos register.

---
 ShaderRecomp/shader.h              |  2 +-
 ShaderRecomp/shader_recompiler.cpp | 12 +++++++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/ShaderRecomp/shader.h b/ShaderRecomp/shader.h
index b2d7873..67968f6 100644
--- a/ShaderRecomp/shader.h
+++ b/ShaderRecomp/shader.h
@@ -31,7 +31,7 @@ struct Shader
     be<uint32_t> physicalOffset;
     be<uint32_t> size;
     be<uint32_t> field8;
-    be<uint32_t> fieldC;
+    be<uint32_t> fieldC; // svPos register: (fieldC >> 8) & 0xFF
     be<uint32_t> field10;
     be<uint32_t> interpolatorInfo; // interpolator count: (interpolatorInfo >> 5) & 0x1F
 };
diff --git a/ShaderRecomp/shader_recompiler.cpp b/ShaderRecomp/shader_recompiler.cpp
index a460fc5..b176723 100644
--- a/ShaderRecomp/shader_recompiler.cpp
+++ b/ShaderRecomp/shader_recompiler.cpp
@@ -1099,7 +1099,17 @@ void ShaderRecompiler::recompile(const uint8_t* shaderData)
     for (size_t i = 0; i < 32; i++)
     {
         if (!printedRegisters[i])
-            println("\tfloat4 r{} = 0.0;", i);
+        {
+            print("\tfloat4 r{} = ", i);
+            if (isPixelShader && i == ((shader->fieldC >> 8) & 0xFF))
+            {
+                out += "float4((iPos.xy - 0.5) * float2(iFace ? 1.0 : -1.0, 1.0), 0.0, 0.0);\n";
+            }
+            else
+            {
+                out += "0.0;\n";
+            }
+        }
     }
 
     out += "\tint a0 = 0;\n";