diff --git a/fixed_wide_vectors/src/affine.rs b/fixed_wide_vectors/src/affine.rs
index 74ba207..f1d3fc3 100644
--- a/fixed_wide_vectors/src/affine.rs
+++ b/fixed_wide_vectors/src/affine.rs
@@ -1,6 +1,9 @@
 use std::ops::Add;
 use fixed_wide_traits::wide::WideDot;
 
+//TODO: replace this with 4x3 matrix
+// mat4x3.wide_dot(vec3.extend(1))
+
 pub struct Affine<M,T>{
     pub matrix:M,
     pub offset:T,