diff --git a/rogueviz/ads/math.cpp b/rogueviz/ads/math.cpp
index 82ca3d99..bddebc4e 100644
--- a/rogueviz/ads/math.cpp
+++ b/rogueviz/ads/math.cpp
@@ -15,8 +15,8 @@ struct ads_point : shiftpoint {
 /** similarly, ads_matrix represents a transformation of the universal cover space */
 struct ads_matrix : shiftmatrix {
   ads_matrix(transmatrix _h = Id, ld _s = 0) { T = _h; shift = _s; }
-  ads_point operator* (ads_point) const;
-  ads_matrix operator* (ads_matrix) const;
+  ads_point operator* (const ads_point&) const;
+  ads_matrix operator* (const ads_matrix&) const;
   ads_point operator* (const hyperpoint& h) const { return ads_point(T*h, shift); }
   ads_matrix operator* (const transmatrix& h) const { return ads_matrix(T*h, shift); }
   ads_matrix(shiftmatrix _s) : shiftmatrix(_s) {}
@@ -61,47 +61,16 @@ transmatrix chg_shift(ld x) {
   return cspin(2, 3, x) * cspin(0, 1, x);
   }
 
-ads_point ads_matrix::operator*(ads_point h) const {
-  auto& T = *this;
-  optimize_shift(h);
-  ld sh = get_shift_cycles(h.shift);
-  h.shift -= sh;
-  auto res0 = T;
-  optimize_shift(res0);
-  auto res1 = res0 * chg_shift(h.shift);
-  optimize_shift(res1);
-  res1.shift += get_shift_cycles(res0.shift - res1.shift);
-  auto res2 = res1 * h.h;
-  optimize_shift(res2);
-  res2.shift += get_shift_cycles(res1.shift - res2.shift);
-  res2.shift += sh;  
-  return res2;
+ads_point ads_matrix::operator*(const ads_point& h) const {
+  return ads_point(twist::nmul(self, h));
   }
 
-ads_matrix ads_matrix::operator*(ads_matrix h) const {
-  auto& T = *this;
-  optimize_shift(h);
-  ld sh = get_shift_cycles(h.shift);
-  h.shift -= sh;
-
-  auto res0 = T;
-  optimize_shift(res0);
-  auto res1 = res0 * chg_shift(h.shift);
-  optimize_shift(res1);
-  res1.shift += get_shift_cycles(res0.shift - res1.shift);
-  auto res2 = res1 * h.T;
-  optimize_shift(res2);
-  res2.shift += get_shift_cycles(res1.shift - res2.shift);
-  res2.shift += sh;
-  return res2;
+ads_matrix ads_matrix::operator*(const ads_matrix& h) const {
+  return ads_matrix(twist::nmul(self, h));
   }
 
 ads_matrix ads_inverse(const ads_matrix& T) {
-  ads_matrix res(inverse(unshift(T)), 0);
-  ads_matrix m = res * T;
-  optimize_shift(m);
-  res.shift -= m.shift;
-  return res;
+  return ads_matrix(twist::ninverse(T));
   }
 
 struct cross_result {