ShaderGen: Omit some unused varyings when possible

Removes the clipPos varying unless slow-depth is used, and the
clipDistance varyings if geometry shaders are not used.

7 files changed, 107 insertions, 74 deletions

diff --git a/Source/Core/VideoCommon/GeometryShaderGen.cpp b/Source/Core/VideoCommon/GeometryShaderGen.cpp
index f5b7b1b35e..e6fa3d3913 100644
--- a/Source/Core/VideoCommon/GeometryShaderGen.cpp
+++ b/Source/Core/VideoCommon/GeometryShaderGen.cpp
@@ -39,11 +39,9 @@ GeometryShaderUid GetGeometryShaderUid(PrimitiveType primitive_type)
 
 static void EmitVertex(ShaderCode& out, const ShaderHostConfig& host_config,
                        const geometry_shader_uid_data* uid_data, const char* vertex,
-                       APIType ApiType, bool wireframe, bool pixel_lighting,
-                       bool first_vertex = false);
+                       APIType ApiType, bool wireframe, bool first_vertex = false);
 static void EndPrimitive(ShaderCode& out, const ShaderHostConfig& host_config,
-                         const geometry_shader_uid_data* uid_data, APIType ApiType, bool wireframe,
-                         bool pixel_lighting);
+                         const geometry_shader_uid_data* uid_data, APIType ApiType, bool wireframe);
 
 ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& host_config,
                                       const geometry_shader_uid_data* uid_data)
@@ -52,7 +50,6 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
   // Non-uid template parameters will write to the dummy data (=> gets optimized out)
 
   const bool wireframe = host_config.wireframe;
-  const bool pixel_lighting = g_ActiveConfig.bEnablePixelLighting;
   const bool msaa = host_config.msaa;
   const bool ssaa = host_config.ssaa;
   const bool stereo = host_config.stereo;
@@ -96,7 +93,7 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
             "};\n");
 
   out.Write("struct VS_OUTPUT {\n");
-  GenerateVSOutputMembers<ShaderCode>(out, ApiType, uid_data->numTexGens, pixel_lighting, "");
+  GenerateVSOutputMembers<ShaderCode>(out, ApiType, uid_data->numTexGens, host_config, "");
   out.Write("};\n");
 
   if (ApiType == APIType::OpenGL || ApiType == APIType::Vulkan)
@@ -105,12 +102,12 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
       out.Write("#define InstanceID gl_InvocationID\n");
 
     out.Write("VARYING_LOCATION(0) in VertexData {\n");
-    GenerateVSOutputMembers<ShaderCode>(out, ApiType, uid_data->numTexGens, pixel_lighting,
+    GenerateVSOutputMembers<ShaderCode>(out, ApiType, uid_data->numTexGens, host_config,
                                         GetInterpolationQualifier(msaa, ssaa, true, true));
     out.Write("} vs[%d];\n", vertex_in);
 
     out.Write("VARYING_LOCATION(0) out VertexData {\n");
-    GenerateVSOutputMembers<ShaderCode>(out, ApiType, uid_data->numTexGens, pixel_lighting,
+    GenerateVSOutputMembers<ShaderCode>(out, ApiType, uid_data->numTexGens, host_config,
                                         GetInterpolationQualifier(msaa, ssaa, true, false));
 
     if (stereo)
@@ -152,8 +149,8 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
     if (ApiType == APIType::OpenGL || ApiType == APIType::Vulkan)
     {
       out.Write("\tVS_OUTPUT start, end;\n");
-      AssignVSOutputMembers(out, "start", "vs[0]", uid_data->numTexGens, pixel_lighting);
-      AssignVSOutputMembers(out, "end", "vs[1]", uid_data->numTexGens, pixel_lighting);
+      AssignVSOutputMembers(out, "start", "vs[0]", uid_data->numTexGens, host_config);
+      AssignVSOutputMembers(out, "end", "vs[1]", uid_data->numTexGens, host_config);
     }
     else
     {
@@ -183,7 +180,7 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
     if (ApiType == APIType::OpenGL || ApiType == APIType::Vulkan)
     {
       out.Write("\tVS_OUTPUT center;\n");
-      AssignVSOutputMembers(out, "center", "vs[0]", uid_data->numTexGens, pixel_lighting);
+      AssignVSOutputMembers(out, "center", "vs[0]", uid_data->numTexGens, host_config);
     }
     else
     {
@@ -214,7 +211,7 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
   if (ApiType == APIType::OpenGL || ApiType == APIType::Vulkan)
   {
     out.Write("\tVS_OUTPUT f;\n");
-    AssignVSOutputMembers(out, "f", "vs[i]", uid_data->numTexGens, pixel_lighting);
+    AssignVSOutputMembers(out, "f", "vs[i]", uid_data->numTexGens, host_config);
 
     if (host_config.backend_depth_clamp &&
         DriverDetails::HasBug(DriverDetails::BUG_BROKEN_CLIP_DISTANCE))
@@ -266,8 +263,8 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
     }
     out.Write("\t}\n");
 
-    EmitVertex(out, host_config, uid_data, "l", ApiType, wireframe, pixel_lighting, true);
-    EmitVertex(out, host_config, uid_data, "r", ApiType, wireframe, pixel_lighting);
+    EmitVertex(out, host_config, uid_data, "l", ApiType, wireframe, true);
+    EmitVertex(out, host_config, uid_data, "r", ApiType, wireframe);
   }
   else if (primitive_type == PrimitiveType::Points)
   {
@@ -295,19 +292,19 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
     }
     out.Write("\t}\n");
 
-    EmitVertex(out, host_config, uid_data, "ll", ApiType, wireframe, pixel_lighting, true);
-    EmitVertex(out, host_config, uid_data, "lr", ApiType, wireframe, pixel_lighting);
-    EmitVertex(out, host_config, uid_data, "ul", ApiType, wireframe, pixel_lighting);
-    EmitVertex(out, host_config, uid_data, "ur", ApiType, wireframe, pixel_lighting);
+    EmitVertex(out, host_config, uid_data, "ll", ApiType, wireframe, true);
+    EmitVertex(out, host_config, uid_data, "lr", ApiType, wireframe);
+    EmitVertex(out, host_config, uid_data, "ul", ApiType, wireframe);
+    EmitVertex(out, host_config, uid_data, "ur", ApiType, wireframe);
   }
   else
   {
-    EmitVertex(out, host_config, uid_data, "f", ApiType, wireframe, pixel_lighting, true);
+    EmitVertex(out, host_config, uid_data, "f", ApiType, wireframe, true);
   }
 
   out.Write("\t}\n");
 
-  EndPrimitive(out, host_config, uid_data, ApiType, wireframe, pixel_lighting);
+  EndPrimitive(out, host_config, uid_data, ApiType, wireframe);
 
   if (stereo && !host_config.backend_gs_instancing)
     out.Write("\t}\n");
@@ -319,7 +316,7 @@ ShaderCode GenerateGeometryShaderCode(APIType ApiType, const ShaderHostConfig& h
 
 static void EmitVertex(ShaderCode& out, const ShaderHostConfig& host_config,
                        const geometry_shader_uid_data* uid_data, const char* vertex,
-                       APIType ApiType, bool wireframe, bool pixel_lighting, bool first_vertex)
+                       APIType ApiType, bool wireframe, bool first_vertex)
 {
   if (wireframe && first_vertex)
     out.Write("\tif (i == 0) first = %s;\n", vertex);
@@ -332,14 +329,14 @@ static void EmitVertex(ShaderCode& out, const ShaderHostConfig& host_config,
       out.Write("\tgl_ClipDistance[0] = %s.clipDist0;\n", vertex);
       out.Write("\tgl_ClipDistance[1] = %s.clipDist1;\n", vertex);
     }
-    AssignVSOutputMembers(out, "ps", vertex, uid_data->numTexGens, pixel_lighting);
+    AssignVSOutputMembers(out, "ps", vertex, uid_data->numTexGens, host_config);
   }
   else if (ApiType == APIType::Vulkan)
   {
     // Vulkan NDC space has Y pointing down (right-handed NDC space).
     out.Write("\tgl_Position = %s.pos;\n", vertex);
     out.Write("\tgl_Position.y = -gl_Position.y;\n");
-    AssignVSOutputMembers(out, "ps", vertex, uid_data->numTexGens, pixel_lighting);
+    AssignVSOutputMembers(out, "ps", vertex, uid_data->numTexGens, host_config);
   }
   else
   {
@@ -353,11 +350,10 @@ static void EmitVertex(ShaderCode& out, const ShaderHostConfig& host_config,
 }
 
 static void EndPrimitive(ShaderCode& out, const ShaderHostConfig& host_config,
-                         const geometry_shader_uid_data* uid_data, APIType ApiType, bool wireframe,
-                         bool pixel_lighting)
+                         const geometry_shader_uid_data* uid_data, APIType ApiType, bool wireframe)
 {
   if (wireframe)
-    EmitVertex(out, host_config, uid_data, "first", ApiType, wireframe, pixel_lighting);
+    EmitVertex(out, host_config, uid_data, "first", ApiType, wireframe);
 
   if (ApiType == APIType::OpenGL || ApiType == APIType::Vulkan)
     out.Write("\tEndPrimitive();\n");
diff --git a/Source/Core/VideoCommon/PixelShaderGen.cpp b/Source/Core/VideoCommon/PixelShaderGen.cpp
index 936dd8e937..ce42363d19 100644
--- a/Source/Core/VideoCommon/PixelShaderGen.cpp
+++ b/Source/Core/VideoCommon/PixelShaderGen.cpp
@@ -351,7 +351,7 @@ void ClearUnusedPixelShaderUidBits(APIType ApiType, const ShaderHostConfig& host
 }
 
 void WritePixelShaderCommonHeader(ShaderCode& out, APIType ApiType, u32 num_texgens,
-                                  bool per_pixel_lighting, bool bounding_box)
+                                  const ShaderHostConfig& host_config, bool bounding_box)
 {
   // dot product for integer vectors
   out.Write("int idot(int3 x, int3 y)\n"
@@ -430,7 +430,7 @@ void WritePixelShaderCommonHeader(ShaderCode& out, APIType ApiType, u32 num_texg
             "#define bpmem_tevorder(i) (bpmem_pack2[(i)].x)\n"
             "#define bpmem_tevksel(i) (bpmem_pack2[(i)].y)\n\n");
 
-  if (per_pixel_lighting)
+  if (host_config.per_pixel_lighting)
   {
     out.Write("%s", s_lighting_struct);
 
@@ -458,7 +458,7 @@ void WritePixelShaderCommonHeader(ShaderCode& out, APIType ApiType, u32 num_texg
   }
 
   out.Write("struct VS_OUTPUT {\n");
-  GenerateVSOutputMembers(out, ApiType, num_texgens, per_pixel_lighting, "");
+  GenerateVSOutputMembers(out, ApiType, num_texgens, host_config, "");
   out.Write("};\n");
 }
 
@@ -491,7 +491,7 @@ ShaderCode GeneratePixelShaderCode(APIType ApiType, const ShaderHostConfig& host
             uid_data->genMode_numindstages);
 
   // Stuff that is shared between ubershaders and pixelgen.
-  WritePixelShaderCommonHeader(out, ApiType, uid_data->genMode_numtexgens, per_pixel_lighting,
+  WritePixelShaderCommonHeader(out, ApiType, uid_data->genMode_numtexgens, host_config,
                                uid_data->bounding_box);
 
   if (uid_data->forced_early_z && g_ActiveConfig.backend_info.bSupportsEarlyZ)
@@ -591,7 +591,7 @@ ShaderCode GeneratePixelShaderCode(APIType ApiType, const ShaderHostConfig& host
     if (host_config.backend_geometry_shaders || ApiType == APIType::Vulkan)
     {
       out.Write("VARYING_LOCATION(0) in VertexData {\n");
-      GenerateVSOutputMembers(out, ApiType, uid_data->genMode_numtexgens, per_pixel_lighting,
+      GenerateVSOutputMembers(out, ApiType, uid_data->genMode_numtexgens, host_config,
                               GetInterpolationQualifier(msaa, ssaa, true, true));
 
       if (stereo)
@@ -609,7 +609,8 @@ ShaderCode GeneratePixelShaderCode(APIType ApiType, const ShaderHostConfig& host
       {
         out.Write("%s in float3 tex%d;\n", GetInterpolationQualifier(msaa, ssaa), i);
       }
-      out.Write("%s in float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
+      if (!host_config.fast_depth_calc)
+        out.Write("%s in float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
       if (per_pixel_lighting)
       {
         out.Write("%s in float3 Normal;\n", GetInterpolationQualifier(msaa, ssaa));
@@ -646,8 +647,11 @@ ShaderCode GeneratePixelShaderCode(APIType ApiType, const ShaderHostConfig& host
     for (unsigned int i = 0; i < uid_data->genMode_numtexgens; ++i)
       out.Write(",\n  in %s float3 tex%d : TEXCOORD%d", GetInterpolationQualifier(msaa, ssaa), i,
                 i);
-    out.Write(",\n  in %s float4 clipPos : TEXCOORD%d", GetInterpolationQualifier(msaa, ssaa),
-              uid_data->genMode_numtexgens);
+    if (!host_config.fast_depth_calc)
+    {
+      out.Write(",\n  in %s float4 clipPos : TEXCOORD%d", GetInterpolationQualifier(msaa, ssaa),
+                uid_data->genMode_numtexgens);
+    }
     if (per_pixel_lighting)
     {
       out.Write(",\n  in %s float3 Normal : TEXCOORD%d", GetInterpolationQualifier(msaa, ssaa),
@@ -655,8 +659,11 @@ ShaderCode GeneratePixelShaderCode(APIType ApiType, const ShaderHostConfig& host
       out.Write(",\n  in %s float3 WorldPos : TEXCOORD%d", GetInterpolationQualifier(msaa, ssaa),
                 uid_data->genMode_numtexgens + 2);
     }
-    out.Write(",\n  in float clipDist0 : SV_ClipDistance0\n");
-    out.Write(",\n  in float clipDist1 : SV_ClipDistance1\n");
+    if (host_config.backend_geometry_shaders)
+    {
+      out.Write(",\n  in float clipDist0 : SV_ClipDistance0\n");
+      out.Write(",\n  in float clipDist1 : SV_ClipDistance1\n");
+    }
     if (stereo)
       out.Write(",\n  in uint layer : SV_RenderTargetArrayIndex\n");
     out.Write("        ) {\n");
diff --git a/Source/Core/VideoCommon/PixelShaderGen.h b/Source/Core/VideoCommon/PixelShaderGen.h
index da5137b8cb..91c19300ba 100644
--- a/Source/Core/VideoCommon/PixelShaderGen.h
+++ b/Source/Core/VideoCommon/PixelShaderGen.h
@@ -167,7 +167,7 @@ typedef ShaderUid<pixel_shader_uid_data> PixelShaderUid;
 ShaderCode GeneratePixelShaderCode(APIType ApiType, const ShaderHostConfig& host_config,
                                    const pixel_shader_uid_data* uid_data);
 void WritePixelShaderCommonHeader(ShaderCode& out, APIType ApiType, u32 num_texgens,
-                                  bool per_pixel_lighting, bool bounding_box);
+                                  const ShaderHostConfig& host_config, bool bounding_box);
 void ClearUnusedPixelShaderUidBits(APIType ApiType, const ShaderHostConfig& host_config,
                                    PixelShaderUid* uid);
 PixelShaderUid GetPixelShaderUid();
diff --git a/Source/Core/VideoCommon/ShaderGenCommon.h b/Source/Core/VideoCommon/ShaderGenCommon.h
index 85534b164b..83416d06d4 100644
--- a/Source/Core/VideoCommon/ShaderGenCommon.h
+++ b/Source/Core/VideoCommon/ShaderGenCommon.h
@@ -214,7 +214,7 @@ inline void DefineOutputMember(T& object, APIType api_type, const char* qualifie
 
 template <class T>
 inline void GenerateVSOutputMembers(T& object, APIType api_type, u32 texgens,
-                                    bool per_pixel_lighting, const char* qualifier)
+                                    const ShaderHostConfig& host_config, const char* qualifier)
 {
   DefineOutputMember(object, api_type, qualifier, "float4", "pos", -1, "POSITION");
   DefineOutputMember(object, api_type, qualifier, "float4", "colors_", 0, "COLOR", 0);
@@ -223,9 +223,10 @@ inline void GenerateVSOutputMembers(T& object, APIType api_type, u32 texgens,
   for (unsigned int i = 0; i < texgens; ++i)
     DefineOutputMember(object, api_type, qualifier, "float3", "tex", i, "TEXCOORD", i);
 
-  DefineOutputMember(object, api_type, qualifier, "float4", "clipPos", -1, "TEXCOORD", texgens);
+  if (!host_config.fast_depth_calc)
+    DefineOutputMember(object, api_type, qualifier, "float4", "clipPos", -1, "TEXCOORD", texgens);
 
-  if (per_pixel_lighting)
+  if (host_config.per_pixel_lighting)
   {
     DefineOutputMember(object, api_type, qualifier, "float3", "Normal", -1, "TEXCOORD",
                        texgens + 1);
@@ -233,13 +234,16 @@ inline void GenerateVSOutputMembers(T& object, APIType api_type, u32 texgens,
                        texgens + 2);
   }
 
-  DefineOutputMember(object, api_type, qualifier, "float", "clipDist", 0, "SV_ClipDistance", 0);
-  DefineOutputMember(object, api_type, qualifier, "float", "clipDist", 1, "SV_ClipDistance", 1);
+  if (host_config.backend_geometry_shaders)
+  {
+    DefineOutputMember(object, api_type, qualifier, "float", "clipDist", 0, "SV_ClipDistance", 0);
+    DefineOutputMember(object, api_type, qualifier, "float", "clipDist", 1, "SV_ClipDistance", 1);
+  }
 }
 
 template <class T>
 inline void AssignVSOutputMembers(T& object, const char* a, const char* b, u32 texgens,
-                                  bool per_pixel_lighting)
+                                  const ShaderHostConfig& host_config)
 {
   object.Write("\t%s.pos = %s.pos;\n", a, b);
   object.Write("\t%s.colors_0 = %s.colors_0;\n", a, b);
@@ -248,16 +252,20 @@ inline void AssignVSOutputMembers(T& object, const char* a, const char* b, u32 t
   for (unsigned int i = 0; i < texgens; ++i)
     object.Write("\t%s.tex%d = %s.tex%d;\n", a, i, b, i);
 
-  object.Write("\t%s.clipPos = %s.clipPos;\n", a, b);
+  if (!host_config.fast_depth_calc)
+    object.Write("\t%s.clipPos = %s.clipPos;\n", a, b);
 
-  if (per_pixel_lighting)
+  if (host_config.per_pixel_lighting)
   {
     object.Write("\t%s.Normal = %s.Normal;\n", a, b);
     object.Write("\t%s.WorldPos = %s.WorldPos;\n", a, b);
   }
 
-  object.Write("\t%s.clipDist0 = %s.clipDist0;\n", a, b);
-  object.Write("\t%s.clipDist1 = %s.clipDist1;\n", a, b);
+  if (host_config.backend_geometry_shaders)
+  {
+    object.Write("\t%s.clipDist0 = %s.clipDist0;\n", a, b);
+    object.Write("\t%s.clipDist1 = %s.clipDist1;\n", a, b);
+  }
 }
 
 // We use the flag "centroid" to fix some MSAA rendering bugs. With MSAA, the
diff --git a/Source/Core/VideoCommon/UberShaderPixel.cpp b/Source/Core/VideoCommon/UberShaderPixel.cpp
index 4d66fac968..0d5d733fa2 100644
--- a/Source/Core/VideoCommon/UberShaderPixel.cpp
+++ b/Source/Core/VideoCommon/UberShaderPixel.cpp
@@ -59,7 +59,7 @@ ShaderCode GenPixelShader(APIType ApiType, const ShaderHostConfig& host_config,
 
   out.Write("// Pixel UberShader for %u texgens%s%s\n", numTexgen,
             early_depth ? ", early-depth" : "", per_pixel_depth ? ", per-pixel depth" : "");
-  WritePixelShaderCommonHeader(out, ApiType, numTexgen, per_pixel_lighting, bounding_box);
+  WritePixelShaderCommonHeader(out, ApiType, numTexgen, host_config, bounding_box);
   WriteUberShaderCommonHeader(out, ApiType, host_config);
   if (per_pixel_lighting)
     WriteLightingFunction(out);
@@ -106,7 +106,7 @@ ShaderCode GenPixelShader(APIType ApiType, const ShaderHostConfig& host_config,
     if (host_config.backend_geometry_shaders || ApiType == APIType::Vulkan)
     {
       out.Write("VARYING_LOCATION(0) in VertexData {\n");
-      GenerateVSOutputMembers(out, ApiType, numTexgen, per_pixel_lighting,
+      GenerateVSOutputMembers(out, ApiType, numTexgen, host_config,
                               GetInterpolationQualifier(msaa, ssaa, true, true));
 
       if (stereo)
@@ -122,7 +122,8 @@ ShaderCode GenPixelShader(APIType ApiType, const ShaderHostConfig& host_config,
       // Let's set up attributes
       for (u32 i = 0; i < numTexgen; ++i)
         out.Write("%s in float3 tex%d;\n", GetInterpolationQualifier(msaa, ssaa), i);
-      out.Write("%s in float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
+      if (!host_config.fast_depth_calc)
+        out.Write("%s in float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
       if (per_pixel_lighting)
       {
         out.Write("%s in float3 Normal;\n", GetInterpolationQualifier(msaa, ssaa));
@@ -709,8 +710,11 @@ ShaderCode GenPixelShader(APIType ApiType, const ShaderHostConfig& host_config,
     for (u32 i = 0; i < numTexgen; ++i)
       out.Write(",\n  in %s float3 tex%u : TEXCOORD%u", GetInterpolationQualifier(msaa, ssaa), i,
                 i);
-    out.Write("\n,\n  in %s float4 clipPos : TEXCOORD%u", GetInterpolationQualifier(msaa, ssaa),
-              numTexgen);
+    if (!host_config.fast_depth_calc)
+    {
+      out.Write("\n,\n  in %s float4 clipPos : TEXCOORD%u", GetInterpolationQualifier(msaa, ssaa),
+                numTexgen);
+    }
     if (per_pixel_lighting)
     {
       out.Write(",\n  in %s float3 Normal : TEXCOORD%u", GetInterpolationQualifier(msaa, ssaa),
diff --git a/Source/Core/VideoCommon/UberShaderVertex.cpp b/Source/Core/VideoCommon/UberShaderVertex.cpp
index bf24f6afda..af2b12110c 100644
--- a/Source/Core/VideoCommon/UberShaderVertex.cpp
+++ b/Source/Core/VideoCommon/UberShaderVertex.cpp
@@ -45,7 +45,7 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
   out.Write("};\n");
 
   out.Write("struct VS_OUTPUT {\n");
-  GenerateVSOutputMembers(out, ApiType, numTexgen, per_pixel_lighting, "");
+  GenerateVSOutputMembers(out, ApiType, numTexgen, host_config, "");
   out.Write("};\n\n");
 
   WriteUberShaderCommonHeader(out, ApiType, host_config);
@@ -67,7 +67,7 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
     if (host_config.backend_geometry_shaders || ApiType == APIType::Vulkan)
     {
       out.Write("VARYING_LOCATION(0) out VertexData {\n");
-      GenerateVSOutputMembers(out, ApiType, numTexgen, per_pixel_lighting,
+      GenerateVSOutputMembers(out, ApiType, numTexgen, host_config,
                               GetInterpolationQualifier(msaa, ssaa, true, false));
       out.Write("} vs;\n");
     }
@@ -77,7 +77,8 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
       for (u32 i = 0; i < numTexgen; ++i)
         out.Write("%s out float3 tex%u;\n", GetInterpolationQualifier(msaa, ssaa), i);
 
-      out.Write("%s out float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
+      if (!host_config.fast_depth_calc)
+        out.Write("%s out float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
       if (per_pixel_lighting)
       {
         out.Write("%s out float3 Normal;\n", GetInterpolationQualifier(msaa, ssaa));
@@ -184,8 +185,11 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
   out.Write("    o.colors_1 = float4(1.0, 1.0, 1.0, 1.0);\n");
   out.Write("}\n");
 
-  // clipPos/w needs to be done in pixel shader, not here
-  out.Write("o.clipPos = o.pos;\n");
+  if (!host_config.fast_depth_calc)
+  {
+    // clipPos/w needs to be done in pixel shader, not here
+    out.Write("o.clipPos = o.pos;\n");
+  }
 
   if (per_pixel_lighting)
   {
@@ -207,8 +211,13 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
     // We adjust our depth value for clipping purposes to match the perspective projection in the
     // software backend, which is a hack to fix Sonic Adventure and Unleashed games.
     out.Write("float clipDepth = o.pos.z * (1.0 - 1e-7);\n");
-    out.Write("o.clipDist0 = clipDepth + o.pos.w;\n");  // Near: z < -w
-    out.Write("o.clipDist1 = -clipDepth;\n");           // Far: z > 0
+    out.Write("float clipDist0 = clipDepth + o.pos.w;\n");  // Near: z < -w
+    out.Write("float clipDist1 = -clipDepth;\n");           // Far: z > 0
+    if (host_config.backend_geometry_shaders)
+    {
+      out.Write("o.clipDist0 = clipDist0;\n");
+      out.Write("o.clipDist1 = clipDist1;\n");
+    }
   }
 
   // Write the true depth value. If the game uses depth textures, then the pixel shader will
@@ -269,7 +278,7 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
   {
     if (host_config.backend_geometry_shaders || ApiType == APIType::Vulkan)
     {
-      AssignVSOutputMembers(out, "vs", "o", numTexgen, per_pixel_lighting);
+      AssignVSOutputMembers(out, "vs", "o", numTexgen, host_config);
     }
     else
     {
@@ -277,7 +286,8 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
       // are not supported, however that will require at least OpenGL 3.2 support.
       for (u32 i = 0; i < numTexgen; ++i)
         out.Write("tex%d.xyz = o.tex%d;\n", i, i);
-      out.Write("clipPos = o.clipPos;\n");
+      if (!host_config.fast_depth_calc)
+        out.Write("clipPos = o.clipPos;\n");
       if (per_pixel_lighting)
       {
         out.Write("Normal = o.Normal;\n");
@@ -289,8 +299,8 @@ ShaderCode GenVertexShader(APIType ApiType, const ShaderHostConfig& host_config,
 
     if (host_config.backend_depth_clamp)
     {
-      out.Write("gl_ClipDistance[0] = o.clipDist0;\n");
-      out.Write("gl_ClipDistance[1] = o.clipDist1;\n");
+      out.Write("gl_ClipDistance[0] = clipDist0;\n");
+      out.Write("gl_ClipDistance[1] = clipDist1;\n");
     }
 
     // Vulkan NDC space has Y pointing down (right-handed NDC space).
@@ -477,4 +487,4 @@ void EnumerateVertexShaderUids(const std::function<void(const VertexShaderUid&)>
     callback(uid);
   }
 }
-}
+}  // namespace UberShader
diff --git a/Source/Core/VideoCommon/VertexShaderGen.cpp b/Source/Core/VideoCommon/VertexShaderGen.cpp
index ccec60731c..2c89b368ad 100644
--- a/Source/Core/VideoCommon/VertexShaderGen.cpp
+++ b/Source/Core/VideoCommon/VertexShaderGen.cpp
@@ -98,7 +98,7 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
   out.Write("};\n");
 
   out.Write("struct VS_OUTPUT {\n");
-  GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, per_pixel_lighting, "");
+  GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, host_config, "");
   out.Write("};\n");
 
   if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
@@ -132,7 +132,7 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
     if (host_config.backend_geometry_shaders || api_type == APIType::Vulkan)
     {
       out.Write("VARYING_LOCATION(0) out VertexData {\n");
-      GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, per_pixel_lighting,
+      GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, host_config,
                               GetInterpolationQualifier(msaa, ssaa, true, false));
       out.Write("} vs;\n");
     }
@@ -146,7 +146,8 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
           out.Write("%s out float3 tex%u;\n", GetInterpolationQualifier(msaa, ssaa), i);
         }
       }
-      out.Write("%s out float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
+      if (!host_config.fast_depth_calc)
+        out.Write("%s out float4 clipPos;\n", GetInterpolationQualifier(msaa, ssaa));
       if (per_pixel_lighting)
       {
         out.Write("%s out float3 Normal;\n", GetInterpolationQualifier(msaa, ssaa));
@@ -398,7 +399,8 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
   }
 
   // clipPos/w needs to be done in pixel shader, not here
-  out.Write("o.clipPos = o.pos;\n");
+  if (!host_config.fast_depth_calc)
+    out.Write("o.clipPos = o.pos;\n");
 
   if (per_pixel_lighting)
   {
@@ -422,8 +424,13 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
     // We adjust our depth value for clipping purposes to match the perspective projection in the
     // software backend, which is a hack to fix Sonic Adventure and Unleashed games.
     out.Write("float clipDepth = o.pos.z * (1.0 - 1e-7);\n");
-    out.Write("o.clipDist0 = clipDepth + o.pos.w;\n");  // Near: z < -w
-    out.Write("o.clipDist1 = -clipDepth;\n");           // Far: z > 0
+    out.Write("float clipDist0 = clipDepth + o.pos.w;\n");  // Near: z < -w
+    out.Write("float clipDist1 = -clipDepth;\n");           // Far: z > 0
+    if (host_config.backend_geometry_shaders)
+    {
+      out.Write("o.clipDist0 = clipDist0;\n");
+      out.Write("o.clipDist1 = clipDist1;\n");
+    }
   }
 
   // Write the true depth value. If the game uses depth textures, then the pixel shader will
@@ -487,7 +494,7 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
   {
     if (host_config.backend_geometry_shaders || api_type == APIType::Vulkan)
     {
-      AssignVSOutputMembers(out, "vs", "o", uid_data->numTexGens, per_pixel_lighting);
+      AssignVSOutputMembers(out, "vs", "o", uid_data->numTexGens, host_config);
     }
     else
     {
@@ -495,7 +502,8 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
       // are not supported, however that will require at least OpenGL 3.2 support.
       for (unsigned int i = 0; i < uid_data->numTexGens; ++i)
         out.Write("tex%d.xyz = o.tex%d;\n", i, i);
-      out.Write("clipPos = o.clipPos;\n");
+      if (!host_config.fast_depth_calc)
+        out.Write("clipPos = o.clipPos;\n");
       if (per_pixel_lighting)
       {
         out.Write("Normal = o.Normal;\n");
@@ -507,8 +515,8 @@ ShaderCode GenerateVertexShaderCode(APIType api_type, const ShaderHostConfig& ho
 
     if (host_config.backend_depth_clamp)
     {
-      out.Write("gl_ClipDistance[0] = o.clipDist0;\n");
-      out.Write("gl_ClipDistance[1] = o.clipDist1;\n");
+      out.Write("gl_ClipDistance[0] = clipDist0;\n");
+      out.Write("gl_ClipDistance[1] = clipDist1;\n");
     }
 
     // Vulkan NDC space has Y pointing down (right-handed NDC space).