diff --git a/rogueviz/ru/entity.cpp b/rogueviz/ru/entity.cpp
index 7719643d..dfd6f57e 100644
--- a/rogueviz/ru/entity.cpp
+++ b/rogueviz/ru/entity.cpp
@@ -619,7 +619,7 @@ xy pendulum_platform::location_at(ld t) {
   auto h1 = to_hyper(a);
   auto h2 = to_hyper(b);
   auto d = hdist(h1, h2);
-  auto x = (1 - cos(t / game_fps * TAU / period)) / 2 * d;
+  auto x = (1 - cos(shift + t / game_fps * TAU / period)) / 2 * d;
   return from_hyper(rgpushxto0(h1) * rspintox(gpushxto0(h1) * h2) * xpush0(x));
   }
 
@@ -643,7 +643,7 @@ xy ellipse_platform::location_at(ld t) {
       }
     lengthsum.push_back(ls);
     }
-  ld our_t = t / (period * game_fps);
+  ld our_t = (t + shift * game_fps) / (period * game_fps);
   our_t -= floor(our_t);
   our_t *= lengthsum.back();
   auto it = lower_bound(lengthsum.begin(), lengthsum.end(), our_t);