diff --git a/src/GPU3D_Soft.h b/src/GPU3D_Soft.h
index 0789ec3d..72ab8816 100644
--- a/src/GPU3D_Soft.h
+++ b/src/GPU3D_Soft.h
@@ -369,6 +369,7 @@ private:
         template<bool swapped>
         constexpr void EdgeParams_XMajor(s32* length, s32* coverage) const
         {
+            // credit to StrikerX3 for working out this weird rounding nonsense
             // only do length calc for right side when swapped as it's
             // only needed for aa calcs, as actual line spans are broken
             if constexpr (!swapped || side)