1 files changed, 39 insertions, 0 deletions
diff --git a/src/Ryujinx.Graphics.Shader/CodeGen/Spirv/IoMap.cs b/src/Ryujinx.Graphics.Shader/CodeGen/Spirv/IoMap.cs
index 8a610323..08d403e2 100644
--- a/src/Ryujinx.Graphics.Shader/CodeGen/Spirv/IoMap.cs
+++ b/src/Ryujinx.Graphics.Shader/CodeGen/Spirv/IoMap.cs
@@ -1,5 +1,6 @@
 using Ryujinx.Graphics.Shader.IntermediateRepresentation;
 using Ryujinx.Graphics.Shader.Translation;
+using System;
 using static Spv.Specification;
 
 namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
@@ -80,5 +81,43 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
 
             return false;
         }
+
+        public static bool IsPerVertexBuiltIn(IoVariable ioVariable)
+        {
+            switch (ioVariable)
+            {
+                case IoVariable.Position:
+                case IoVariable.PointSize:
+                case IoVariable.ClipDistance:
+                    return true;
+            }
+
+            return false;
+        }
+
+        public static bool IsPerVertexArrayBuiltIn(StorageKind storageKind, ShaderStage stage)
+        {
+            if (storageKind == StorageKind.Output)
+            {
+                return stage == ShaderStage.TessellationControl;
+            }
+            else
+            {
+                return stage == ShaderStage.TessellationControl ||
+                       stage == ShaderStage.TessellationEvaluation ||
+                       stage == ShaderStage.Geometry;
+            }
+        }
+
+        public static int GetPerVertexStructFieldIndex(IoVariable ioVariable)
+        {
+            return ioVariable switch
+            {
+                IoVariable.Position => 0,
+                IoVariable.PointSize => 1,
+                IoVariable.ClipDistance => 2,
+                _ => throw new ArgumentException($"Invalid built-in variable {ioVariable}.")
+            };
+        }
     }
 }