diff --git a/LEGO1/realtime/matrix4d.inl.h b/LEGO1/realtime/matrix4d.inl.h
index f3f61ff3..c1643f76 100644
--- a/LEGO1/realtime/matrix4d.inl.h
+++ b/LEGO1/realtime/matrix4d.inl.h
@@ -290,6 +290,8 @@ void Matrix4::RotateZ(const float& p_angle)
 // FUNCTION: BETA10 0x1005a590
 int Matrix4::Invert(Matrix4& p_mat)
 {
+	// Inlined at LEGO1 0x1006b2d3
+
 	float copyData[4][4];
 	Matrix4 copy(copyData);
 	copy = *this;
@@ -312,6 +314,7 @@ int Matrix4::Invert(Matrix4& p_mat)
 		}
 
 		if (copy[i][i] < 0.001f && copy[i][i] > -0.001f) {
+			// FAILURE from mxtypes.h
 			return -1;
 		}
 
@@ -349,6 +352,7 @@ int Matrix4::Invert(Matrix4& p_mat)
 		}
 	}
 
+	// SUCCESS from mxtypes.h
 	return 0;
 }