Add calling convention attributes to unmanaged function pointers.

StbiStreamWrapper.cs

@@ -12,18 +12,23 @@ namespace ReFuel.Stb
     /// <param name="buffer">C array to read into.</param>
     /// <param name="count">Size of the C array in bytes.</param>
     /// <returns>The number of bytes read from the stream.</returns>
+    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
     public unsafe delegate int StbiReadProc(void *userdata, byte* buffer, int count);
+
     /// <summary>
     /// Pointer to STBI stream skip function.
     /// </summary>
     /// <param name="userdata">User provided userdata pointer.</param>
     /// <param name="count">Number of bytes to skip.</param>
+    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
     public unsafe delegate void StbiSkipProc(void *userdata, int count);
+
     /// <summary>
     /// Pointer to STBI stream end of file function.
     /// </summary>
     /// <param name="userdata">User provided userdata pointer.</param>
     /// <returns>Non-zero value if the end of the stream has been reached.</returns>
+    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
     public unsafe delegate int StbiEofProc(void *userdata);
 
     /// <summary>
@@ -123,4 +128,4 @@ namespace ReFuel.Stb
 
         public static implicit operator IntPtr(in StbiWriteStreamWrapper wrapper) => wrapper.Callback;
     }
-}
+}

StbiWrite.cs

@@ -9,6 +9,7 @@ namespace ReFuel.Stb.Native
     /// <param name="context">User provided context pointer.</param>
     /// <param name="data">C Array of data to write.</param>
     /// <param name="size">Size of the C array in bytes.</param>
+    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
     public unsafe delegate void StbiWriteProc(void* context, void* data, int size);
 
     public unsafe partial class Stbi
@@ -24,7 +25,7 @@ namespace ReFuel.Stb.Native
         }
 
         public static int write_png_compression_level
-        { 
+        {
             get => *_png_compression_level_ptr;
             set => *_png_compression_level_ptr = value;
         }