8 files changed, 15 insertions, 16 deletions
diff --git a/src/critter.cpp b/src/critter.cpp
index 0c1e672f..4d275149 100644
--- a/src/critter.cpp
+++ b/src/critter.cpp
@@ -4,7 +4,6 @@
 #include "loader/loader.hpp"
 #include "src/world.hpp"
 #include "src/object.hpp"
-#include "src/nanosecond.hpp"
 #include "shaders/shader.hpp"
 #include "compat/exception.hpp"
 #include <cmath>
@@ -144,7 +143,7 @@ Vector2 critter::ordinal_offset(Vector2b offset) const
     return Vector2(offset);
 }
 
-void critter::update(size_t i, Ns dt)
+void critter::update(size_t i, const Ns& dt)
 {
     if (playable)
     {
@@ -164,12 +163,12 @@ void critter::update(size_t i, Ns dt)
         update_nonplayable(i, dt);
 }
 
-void critter::update_nonplayable(size_t i, Ns dt)
+void critter::update_nonplayable(size_t i, const Ns& dt)
 {
     (void)i; (void)dt; (void)playable;
 }
 
-void critter::update_movement(size_t i, Ns dt, rotation new_r)
+void critter::update_movement(size_t i, const Ns& dt, rotation new_r)
 {
     fm_assert(new_r < rotation_COUNT);
     fm_assert(is_dynamic());
diff --git a/src/critter.hpp b/src/critter.hpp
index d3f39e87..8855813a 100644
--- a/src/critter.hpp
+++ b/src/critter.hpp
@@ -29,9 +29,9 @@ struct critter final : object
     object_type type() const noexcept override;
     explicit operator critter_proto() const;
 
-    void update(size_t i, Ns dt) override;
-    void update_movement(size_t i, Ns dt, rotation r);
-    void update_nonplayable(size_t i, Ns dt);
+    void update(size_t i, const Ns& dt) override;
+    void update_movement(size_t i, const Ns& dt, rotation r);
+    void update_nonplayable(size_t i, const Ns& dt);
     void set_keys(bool L, bool R, bool U, bool D);
     void set_keys_auto();
     Vector2 ordinal_offset(Vector2b offset) const override;
diff --git a/src/light.cpp b/src/light.cpp
index 333fb327..0e36fd6d 100644
--- a/src/light.cpp
+++ b/src/light.cpp
@@ -53,7 +53,7 @@ light::operator light_proto() const
 }
 
 object_type light::type() const noexcept { return object_type::light; }
-void light::update(size_t, Ns) {}
+void light::update(size_t, const Ns&) {}
 bool light::is_dynamic() const { return true; }
 bool light::is_virtual() const { return true; }
 
diff --git a/src/light.hpp b/src/light.hpp
index 91709b1b..3d0d3546 100644
--- a/src/light.hpp
+++ b/src/light.hpp
@@ -33,7 +33,7 @@ struct light final : object
     Vector2 ordinal_offset(Vector2b offset) const override;
     float depth_offset() const override;
     object_type type() const noexcept override;
-    void update(size_t i, Ns dt) override;
+    void update(size_t i, const Ns& dt) override;
     bool is_dynamic() const override;
     bool is_virtual() const override;
 
diff --git a/src/object.cpp b/src/object.cpp
index 7f0b9afb..4339e055 100644
--- a/src/object.cpp
+++ b/src/object.cpp
@@ -290,7 +290,7 @@ bool object::move_to(Magnum::Vector2i delta)
 }
 
 template<typename T> requires std::is_unsigned_v<T>
-uint32_t object::alloc_frame_time(Ns dt, T& accum, uint32_t hz, float speed)
+uint32_t object::alloc_frame_time(const Ns& dt, T& accum, uint32_t hz, float speed)
 {
     constexpr auto ns_in_sec = Ns((int)1e9);
     constexpr auto accum_max = uint64_t{limits<T>::max};
@@ -320,8 +320,8 @@ uint32_t object::alloc_frame_time(Ns dt, T& accum, uint32_t hz, float speed)
     return nframes;
 }
 
-template uint32_t object::alloc_frame_time(Ns dt, uint16_t& accum, uint32_t hz, float speed);
-template uint32_t object::alloc_frame_time(Ns dt, uint32_t& accum, uint32_t hz, float speed);
+template uint32_t object::alloc_frame_time(const Ns& dt, uint16_t& accum, uint32_t hz, float speed);
+template uint32_t object::alloc_frame_time(const Ns& dt, uint32_t& accum, uint32_t hz, float speed);
 
 void object::set_bbox_(Vector2b offset_, Vector2b bb_offset_, Vector2ub bb_size_, pass_mode pass_)
 {
diff --git a/src/object.hpp b/src/object.hpp
index 4ada39d4..7b9ab019 100644
--- a/src/object.hpp
+++ b/src/object.hpp
@@ -71,7 +71,7 @@ struct object
     virtual object_type type() const noexcept = 0;
     virtual bool can_activate(size_t i) const;
     virtual bool activate(size_t i);
-    virtual void update(size_t i, Ns dt) = 0;
+    virtual void update(size_t i, const Ns& dt) = 0;
     virtual void rotate(size_t i, rotation r);
     virtual bool can_rotate(global_coords coord, rotation new_r, rotation old_r, Vector2b offset, Vector2b bbox_offset, Vector2ub bbox_size);
     virtual bool can_move_to(Vector2i delta, global_coords coord, Vector2b offset, Vector2b bbox_offset, Vector2ub bbox_aize);
@@ -91,7 +91,7 @@ struct object
 
     template<typename T>
     requires std::is_unsigned_v<T>
-    static uint32_t alloc_frame_time(Ns dt, T& accum, uint32_t hz, float speed);
+    static uint32_t alloc_frame_time(const Ns& dt, T& accum, uint32_t hz, float speed);
 
 protected:
     object(object_id id, class chunk& c, const object_proto& proto);
diff --git a/src/scenery.cpp b/src/scenery.cpp
index d95908c2..701dde1f 100644
--- a/src/scenery.cpp
+++ b/src/scenery.cpp
@@ -146,7 +146,7 @@ bool scenery::can_activate(size_t i) const
     );
 }
 
-void scenery::update(size_t i, Ns dt)
+void scenery::update(size_t i, const Ns& dt)
 {
     return std::visit(
         [&]<typename T>(T& sc) { sc.update(*this, i, dt); },
diff --git a/src/scenery.hpp b/src/scenery.hpp
index 25d40889..cb952320 100644
--- a/src/scenery.hpp
+++ b/src/scenery.hpp
@@ -97,7 +97,7 @@ struct scenery final : object
 {
     scenery_variants subtype;
 
-    void update(size_t i, Ns dt) override;
+    void update(size_t i, const Ns& dt) override;
     Vector2 ordinal_offset(Vector2b offset) const override;
     float depth_offset() const override;
     bool can_activate(size_t i) const override;