wip: don't lock command mutex for each mass/spring in FillGraph()

Current Issues:
- HUGE memory leak
- HUGE amount of needles copying
- FillGraph() does thousands of lock_guards instead of one
- Can no longer rely on new states appearing immediately - have to check
each access
- Physics run as fast as possible, no constant sim speed`
- Irregular long freezes

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.25)
 project(MassSprings)
 
-set(CMAKE_CXX_STANDARD 23)
+set(CMAKE_CXX_STANDARD 26)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 find_package(raylib REQUIRED)

include/config.hpp

@@ -30,7 +30,7 @@ constexpr float ROT_SPEED = 1.0;
 constexpr float CAMERA_SMOOTH_SPEED = 15.0;
 
 // Physics Engine
-constexpr float SIM_SPEED = 4.0;          // How large each update should be
+constexpr float SIM_SPEED = 0.2;          // How large each update should be
 constexpr float TIMESTEP = 1.0 / 90;      // Do 90 physics updates per second
 constexpr float MASS = 1.0;               // Mass spring system
 constexpr float SPRING_CONSTANT = 5.0;    // Mass spring system

include/physics.hpp

@@ -1,9 +1,15 @@
 #ifndef __PHYSICS_HPP_
 #define __PHYSICS_HPP_
 
+#include <atomic>
+#include <mutex>
+#include <queue>
 #include <raylib.h>
 #include <raymath.h>
+#include <thread>
+#include <tracy/Tracy.hpp>
 #include <unordered_map>
+#include <variant>
 #include <vector>
 
 #include "config.hpp"
@@ -77,7 +83,7 @@ public:
   std::unordered_map<std::pair<State, State>, int> state_springs;
 
 public:
-  MassSpringSystem() {
+  MassSpringSystem() : threads(std::thread::hardware_concurrency() - 1) {
 #ifndef BARNES_HUT
     last_build = REPULSION_GRID_REFRESH;
     std::cout << "Using uniform grid repulsion force calculation." << std::endl;
@@ -105,14 +111,13 @@ private:
 #endif
 
 public:
-  auto AddMass(float mass, bool fixed, const State &state) -> void;
+  auto AddMass(const State &state) -> void;
 
   auto GetMass(const State &state) -> Mass &;
 
   auto GetMass(const State &state) const -> const Mass &;
 
-  auto AddSpring(const State &massA, const State &massB, float spring_constant,
-                 float dampening_constant, float rest_length) -> void;
+  auto AddSpring(const State &massA, const State &massB) -> void;
 
   auto Clear() -> void;
 
@@ -129,4 +134,69 @@ public:
 #endif
 };
 
+class ThreadedPhysics {
+  struct AddMass {
+    State s;
+  };
+  struct AddSpring {
+    State a;
+    State b;
+  };
+  struct ClearGraph {};
+
+  using Command = std::variant<AddMass, AddSpring, ClearGraph>;
+
+  struct PhysicsState {
+    TracyLockable(std::mutex, command_mtx);
+    std::queue<Command> pending_commands;
+
+    TracyLockable(std::mutex, pos_mtx);
+    std::vector<Mass> masses;                    // Read by renderer
+    std::unordered_map<State, int> state_masses; // Read by renderer
+    std::vector<Spring> springs;                 // Read by renderer
+    std::unordered_map<std::pair<State, State>, int>
+        state_springs; // Read by renderer
+
+    std::atomic<bool> running{true};
+  };
+
+private:
+  std::thread physics;
+
+public:
+  PhysicsState state;
+
+public:
+  ThreadedPhysics() : physics(PhysicsThread, std::ref(state)) {}
+
+  ThreadedPhysics(const ThreadedPhysics &copy) = delete;
+  ThreadedPhysics &operator=(const ThreadedPhysics &copy) = delete;
+  ThreadedPhysics(ThreadedPhysics &&move) = delete;
+  ThreadedPhysics &operator=(ThreadedPhysics &&move) = delete;
+
+  ~ThreadedPhysics() {
+    state.running = false;
+    physics.join();
+  }
+
+private:
+  static auto PhysicsThread(PhysicsState &state) -> void;
+
+public:
+  auto AddMassCmd(const State &_state) -> void;
+
+  auto AddSpringCmd(const State &a, const State &b) -> void;
+
+  auto ClearCmd() -> void;
+
+  auto AddMassSpringsCmd(const std::unordered_set<State> &masses,
+                         const std::vector<std::pair<State, State>> &springs)
+      -> void;
+};
+
+// https://en.cppreference.com/w/cpp/utility/variant/visit
+template <class... Ts> struct overloads : Ts... {
+  using Ts::operator()...;
+};
+
 #endif

include/renderer.hpp

@@ -61,25 +61,29 @@ public:
   }
 
 private:
-  auto AllocateGraphInstancing(const MassSpringSystem &mass_springs) -> void;
+  auto AllocateGraphInstancing(const std::vector<Mass> &masses) -> void;
 
-  auto
-  ReallocateGraphInstancingIfNecessary(const MassSpringSystem &mass_springs)
+  auto ReallocateGraphInstancingIfNecessary(const std::vector<Mass> &masses)
       -> void;
 
 public:
   auto UpdateTextureSizes() -> void;
 
-  auto DrawMassSprings(const MassSpringSystem &mass_springs,
-                       const State &current_state, const State &starting_state,
-                       const std::unordered_set<State> &winning_states,
-                       const std::unordered_set<State> &visited_states) -> void;
+  auto DrawMassSprings(
+      const std::vector<Mass> &masses,
+      const std::unordered_map<State, int> &state_masses,
+      const std::vector<Spring> &springs,
+      const std::unordered_map<std::pair<State, State>, int> state_springs,
+      const State &current_state, const State &starting_state,
+      const std::unordered_set<State> &winning_states,
+      const std::unordered_set<State> &visited_states) -> void;
 
   auto DrawKlotski(const State &state, int hov_x, int hov_y, int sel_x,
                    int sel_y, int block_add_x, int block_add_y,
                    const WinCondition win_condition) -> void;
 
-  auto DrawMenu(const MassSpringSystem &mass_springs, int current_preset,
+  auto DrawMenu(const std::vector<Mass> &masses,
+                const std::vector<Spring> &springs, int current_preset,
                 const State &current_state,
                 const std::unordered_set<State> &winning_states) -> void;
 

include/state.hpp

@@ -1,7 +1,6 @@
 #ifndef __STATE_HPP_
 #define __STATE_HPP_
 
-#include "config.hpp"
 #include "physics.hpp"
 #include "presets.hpp"
 #include "puzzle.hpp"
@@ -10,7 +9,7 @@
 
 class StateManager {
 public:
-  MassSpringSystem &mass_springs;
+  ThreadedPhysics &physics;
 
   int current_preset;
   State starting_state;
@@ -23,12 +22,12 @@ public:
   std::unordered_set<State> visited_states;
 
 public:
-  StateManager(MassSpringSystem &_mass_springs)
-      : mass_springs(_mass_springs), current_preset(0),
+  StateManager(ThreadedPhysics &_physics)
+      : physics(_physics), current_preset(0),
         starting_state(generators[current_preset]()),
         current_state(starting_state), previous_state(starting_state),
         edited(false) {
-    mass_springs.AddMass(MASS, false, current_state);
+    physics.AddMassCmd(current_state);
   }
 
   StateManager(const StateManager &copy) = delete;

src/main.cpp

@@ -1,3 +1,8 @@
+#include <mutex>
+#include <raylib.h>
+#include <raymath.h>
+#include <tracy/Tracy.hpp>
+
 #include "config.hpp"
 #include "input.hpp"
 #include "physics.hpp"
@@ -5,10 +10,6 @@
 #include "state.hpp"
 #include "tracy.hpp"
 
-#include <raylib.h>
-#include <raymath.h>
-#include <tracy/Tracy.hpp>
-
 // TODO: Klotski state file loading
 //       - File should contain a single state per line, multiple lines possible
 //       - If a file is loaded, the presets should be replaced with the states
@@ -18,7 +19,7 @@
 // TODO: Graph interaction
 //       - Click states to display them in the board
 //       - Find shortest path to any winning state and mark it in the graph
-//         - Also mark the next move along the path on the board
+//       - Also mark the next move along the path on the board
 
 auto main(int argc, char *argv[]) -> int {
   // if (argc < 2) {
@@ -37,20 +38,27 @@ auto main(int argc, char *argv[]) -> int {
   // Game setup
   OrbitCamera3D camera;
   Renderer renderer(camera);
-  MassSpringSystem mass_springs;
-  StateManager state(mass_springs);
+  ThreadedPhysics physics;
+  StateManager state(physics); // TODO: What is this warning?
   InputHandler input(state, renderer);
 
+  std::vector<Mass> masses;                    // Read from physics
+  std::unordered_map<State, int> state_masses; // Read from physics
+  std::vector<Spring> springs;                 // Read from physics
+  std::unordered_map<std::pair<State, State>, int>
+      state_springs; // Read from physics
+
   // Game loop
-  double timestep_accumulator = 0.0;
+  // double timestep_accumulator = 0.0;
   while (!WindowShouldClose()) {
-    timestep_accumulator += GetFrameTime();
+    // timestep_accumulator += GetFrameTime();
 
     // Input update
     state.previous_state = state.current_state;
     input.HandleInput();
     state.UpdateGraph(); // Add state added after user input
 
+    /*
     // Physics update
     if (timestep_accumulator > TIMESTEP) {
       // Do not try to catch up if we're falling behind. Frametimes would get
@@ -63,21 +71,43 @@ auto main(int argc, char *argv[]) -> int {
 
       timestep_accumulator -= TIMESTEP;
     }
+    */
+
+    // Read positions from physics thread
+    // TODO: We're copying a HUGE amount of SHIT, because the state
+    //       representations (std::string, ~100 Bytes) are copied ~3 times per
+    //       spring: state_masses<State, int> and state_springs<<State, State>,
+    //       int>
+    // TODO: Don't download each frame if nothing changed, check for update
+    //       first
+    {
+      std::lock_guard<LockableBase(std::mutex)> lock(physics.state.pos_mtx);
+      masses = physics.state.masses;
+      state_masses = physics.state.state_masses;
+      springs = physics.state.springs;
+      state_springs = physics.state.state_springs;
+    }
 
     // Update the camera after the physics, so target lock is smooth
-    camera.Update(mass_springs.GetMass(state.current_state).position);
+    if (state_masses.contains(state.current_state)) {
+      const Mass &current_mass =
+          masses.at(state_masses.at(state.current_state));
+      camera.Update(current_mass.position);
+    }
 
     // Rendering
     renderer.UpdateTextureSizes();
-    renderer.DrawMassSprings(mass_springs, state.current_state,
-                             state.starting_state, state.winning_states,
-                             state.visited_states);
+    if (masses.size() > 0 && state_masses.contains(state.current_state)) {
+      renderer.DrawMassSprings(masses, state_masses, springs, state_springs,
+                               state.current_state, state.starting_state,
+                               state.winning_states, state.visited_states);
+    }
 
     renderer.DrawKlotski(state.current_state, input.hov_x, input.hov_y,
                          input.sel_x, input.sel_y, input.block_add_x,
                          input.block_add_y, state.CurrentWinCondition());
-    renderer.DrawMenu(mass_springs, state.current_preset, state.current_state,
-                      state.winning_states);
+    renderer.DrawMenu(masses, springs, state.current_preset,
+                      state.current_state, state.winning_states);
     renderer.DrawTextures();
   }
 

src/physics.cpp

@@ -5,6 +5,7 @@
 #include <algorithm>
 #include <cfloat>
 #include <cstddef>
+#include <mutex>
 #include <raylib.h>
 #include <raymath.h>
 #include <tracy/Tracy.hpp>
@@ -69,8 +70,7 @@ auto Spring::CalculateSpringForce(Mass &_mass_a, Mass &_mass_b) const -> void {
   _mass_b.force = Vector3Add(_mass_b.force, force_b);
 }
 
-auto MassSpringSystem::AddMass(float mass, bool fixed, const State &state)
-    -> void {
+auto MassSpringSystem::AddMass(const State &state) -> void {
   if (!state_masses.contains(state)) {
     masses.emplace_back(Vector3Zero());
     std::size_t idx = masses.size() - 1;
@@ -86,9 +86,7 @@ auto MassSpringSystem::GetMass(const State &state) const -> const Mass & {
   return masses.at(state_masses.at(state));
 }
 
-auto MassSpringSystem::AddSpring(const State &state_a, const State &state_b,
-                                 float spring_constant,
-                                 float dampening_constant, float rest_length)
+auto MassSpringSystem::AddSpring(const State &state_a, const State &state_b)
     -> void {
   std::pair<State, State> key = std::make_pair(state_a, state_b);
   if (!state_springs.contains(key)) {
@@ -340,3 +338,88 @@ auto MassSpringSystem::InvalidateGrid() -> void {
   last_springs_count = 0;
 }
 #endif
+
+auto ThreadedPhysics::PhysicsThread(ThreadedPhysics::PhysicsState &state)
+    -> void {
+  MassSpringSystem mass_springs;
+
+  const auto visitor = overloads{
+      [&](const struct AddMass &am) { mass_springs.AddMass(am.s); },
+      [&](const struct AddSpring &as) { mass_springs.AddSpring(as.a, as.b); },
+      [&](const struct ClearGraph &cg) { mass_springs.Clear(); },
+  };
+
+  while (state.running) {
+    // Handle queued commands
+    {
+      std::lock_guard<LockableBase(std::mutex)> lock(state.command_mtx);
+      while (!state.pending_commands.empty()) {
+        Command &cmd = state.pending_commands.front();
+        cmd.visit(visitor);
+        state.pending_commands.pop();
+      }
+    }
+
+    if (mass_springs.masses.empty()) {
+      std::this_thread::sleep_for(std::chrono::milliseconds(1));
+      continue;
+    }
+
+    // Physics update
+    // TODO: I need this thread to run at a constant rate
+    mass_springs.ClearForces();
+    mass_springs.CalculateSpringForces();
+    mass_springs.CalculateRepulsionForces();
+    mass_springs.VerletUpdate(TIMESTEP * SIM_SPEED);
+
+    // TODO: Notify the main thread of update
+    // TODO: Just wait here until the main thread has fetched the data?
+    //       Then only the copying would be sequential, while the main thread
+    //       renders this thread can already calculate the physics...
+    // TODO: Would std::swap help in any way?
+
+    // Publish the positions for the renderer (copy)
+    {
+      std::lock_guard<LockableBase(std::mutex)> lock(state.pos_mtx);
+      state.masses = mass_springs.masses;
+      state.state_masses = mass_springs.state_masses;
+      state.springs = mass_springs.springs;
+      state.state_springs = mass_springs.state_springs;
+    }
+  }
+}
+
+auto ThreadedPhysics::AddMassCmd(const State &_state) -> void {
+  {
+    std::lock_guard<LockableBase(std::mutex)> lock(state.command_mtx);
+    state.pending_commands.push(AddMass{_state});
+  }
+}
+
+auto ThreadedPhysics::AddSpringCmd(const State &a, const State &b) -> void {
+  {
+    std::lock_guard<LockableBase(std::mutex)> lock(state.command_mtx);
+    state.pending_commands.push(AddSpring{a, b});
+  }
+}
+
+auto ThreadedPhysics::ClearCmd() -> void {
+  {
+    std::lock_guard<LockableBase(std::mutex)> lock(state.command_mtx);
+    state.pending_commands.push(ClearGraph{});
+  }
+}
+
+auto ThreadedPhysics::AddMassSpringsCmd(
+    const std::unordered_set<State> &masses,
+    const std::vector<std::pair<State, State>> &springs) -> void {
+  {
+    std::lock_guard<LockableBase(std::mutex)> lock(state.command_mtx);
+    for (const auto &_state : masses) {
+      state.pending_commands.push(AddMass{_state});
+    }
+    for (const auto &[from, to] : springs) {
+      state.pending_commands.push(AddSpring{from, to});
+    }
+  }
+}

src/renderer.cpp

@@ -33,7 +33,7 @@ auto Renderer::UpdateTextureSizes() -> void {
   menu_target = LoadRenderTexture(width * 2, MENU_HEIGHT);
 }
 
-auto Renderer::AllocateGraphInstancing(const MassSpringSystem &mass_springs)
+auto Renderer::AllocateGraphInstancing(const std::vector<Mass> &masses)
     -> void {
   cube_instance = GenMeshCube(VERTEX_SIZE, VERTEX_SIZE, VERTEX_SIZE);
 
@@ -48,38 +48,40 @@ auto Renderer::AllocateGraphInstancing(const MassSpringSystem &mass_springs)
   vertex_mat.maps[MATERIAL_MAP_DIFFUSE].color = VERTEX_COLOR;
   vertex_mat.shader = instancing_shader;
 
-  transforms = (Matrix *)MemAlloc(mass_springs.masses.size() * sizeof(Matrix));
-  transforms_size = mass_springs.masses.size();
+  transforms = (Matrix *)MemAlloc(masses.size() * sizeof(Matrix));
+  transforms_size = masses.size();
 }
 
 auto Renderer::ReallocateGraphInstancingIfNecessary(
-    const MassSpringSystem &mass_springs) -> void {
-  if (transforms_size != mass_springs.masses.size()) {
-    transforms = (Matrix *)MemRealloc(transforms, mass_springs.masses.size() *
-                                                      sizeof(Matrix));
-    transforms_size = mass_springs.masses.size();
+    const std::vector<Mass> &masses) -> void {
+  if (transforms_size != masses.size()) {
+    transforms =
+        (Matrix *)MemRealloc(transforms, masses.size() * sizeof(Matrix));
+    transforms_size = masses.size();
   }
 }
 
-auto Renderer::DrawMassSprings(const MassSpringSystem &mass_springs,
-                               const State &current_state,
-                               const State &starting_state,
-                               const std::unordered_set<State> &winning_states,
-                               const std::unordered_set<State> &visited_states)
-    -> void {
+auto Renderer::DrawMassSprings(
+    const std::vector<Mass> &masses,
+    const std::unordered_map<State, int> &state_masses,
+    const std::vector<Spring> &springs,
+    const std::unordered_map<std::pair<State, State>, int> state_springs,
+    const State &current_state, const State &starting_state,
+    const std::unordered_set<State> &winning_states,
+    const std::unordered_set<State> &visited_states) -> void {
   ZoneScoped;
 
   // Prepare cube instancing
   {
     ZoneNamedN(prepare_masses, "PrepareMasses", true);
-    if (mass_springs.masses.size() < DRAW_VERTICES_LIMIT) {
+    if (masses.size() < DRAW_VERTICES_LIMIT) {
       if (transforms == nullptr) {
-        AllocateGraphInstancing(mass_springs);
+        AllocateGraphInstancing(masses);
       }
-      ReallocateGraphInstancingIfNecessary(mass_springs);
+      ReallocateGraphInstancingIfNecessary(masses);
 
       int i = 0;
-      for (const auto &mass : mass_springs.masses) {
+      for (const auto &mass : masses) {
         transforms[i] =
             MatrixTranslate(mass.position.x, mass.position.y, mass.position.z);
         ++i;
@@ -96,10 +98,10 @@ auto Renderer::DrawMassSprings(const MassSpringSystem &mass_springs,
   {
     ZoneNamedN(draw_springs, "DrawSprings", true);
     rlBegin(RL_LINES);
-    for (const auto &spring : mass_springs.springs) {
+    for (const auto &spring : springs) {
       // We have to do a lookup of the actual mass object, which is slow :(
-      const Mass &a = mass_springs.masses.at(spring.mass_a);
-      const Mass &b = mass_springs.masses.at(spring.mass_b);
+      const Mass &a = masses.at(spring.mass_a);
+      const Mass &b = masses.at(spring.mass_b);
       rlColor4ub(EDGE_COLOR.r, EDGE_COLOR.g, EDGE_COLOR.b, EDGE_COLOR.a);
       rlVertex3f(a.position.x, a.position.y, a.position.z);
       rlVertex3f(b.position.x, b.position.y, b.position.z);
@@ -110,20 +112,19 @@ auto Renderer::DrawMassSprings(const MassSpringSystem &mass_springs,
   // Draw masses (instanced)
   {
     ZoneNamedN(draw_masses, "DrawMasses", true);
-    if (mass_springs.masses.size() < DRAW_VERTICES_LIMIT) {
+    if (masses.size() < DRAW_VERTICES_LIMIT) {
       // NOTE: I don't know if drawing all this inside a shader would make it
       //       much faster... The amount of data sent to the GPU would be
       //       reduced (just positions instead of matrices), but is this
       //       noticable for < 100000 cubes?
-      DrawMeshInstanced(cube_instance, vertex_mat, transforms,
-                        mass_springs.masses.size());
+      DrawMeshInstanced(cube_instance, vertex_mat, transforms, masses.size());
     }
   }
 
   // Mark winning states
   if (mark_solutions || connect_solutions) {
     for (const auto &state : winning_states) {
-      const Mass &winning_mass = mass_springs.GetMass(state);
+      const Mass &winning_mass = masses.at(state_masses.at(state));
       if (mark_solutions) {
         DrawCube(winning_mass.position, 2 * VERTEX_SIZE, 2 * VERTEX_SIZE,
                  2 * VERTEX_SIZE, BLUE);
@@ -131,26 +132,26 @@ auto Renderer::DrawMassSprings(const MassSpringSystem &mass_springs,
 
       if (connect_solutions) {
         DrawLine3D(winning_mass.position,
-                   mass_springs.GetMass(current_state).position, PURPLE);
+                   masses.at(state_masses.at(current_state)).position, PURPLE);
       }
     }
   }
 
   // Mark visited states
   for (const auto &state : visited_states) {
-    const Mass &visited_mass = mass_springs.GetMass(state);
+    const Mass &visited_mass = masses.at(state_masses.at(state));
 
     DrawCube(visited_mass.position, VERTEX_SIZE * 1.5, VERTEX_SIZE * 1.5,
              VERTEX_SIZE * 1.5, PURPLE);
   }
 
   // Mark starting state
-  const Mass &starting_mass = mass_springs.GetMass(starting_state);
+  const Mass &starting_mass = masses.at(state_masses.at(starting_state));
   DrawCube(starting_mass.position, VERTEX_SIZE * 2, VERTEX_SIZE * 2,
            VERTEX_SIZE * 2, ORANGE);
 
   // Mark current state
-  const Mass &current_mass = mass_springs.GetMass(current_state);
+  const Mass &current_mass = masses.at(state_masses.at(current_state));
   DrawCube(current_mass.position, VERTEX_SIZE * 2, VERTEX_SIZE * 2,
            VERTEX_SIZE * 2, RED);
 
@@ -250,8 +251,9 @@ auto Renderer::DrawKlotski(const State &state, int hov_x, int hov_y, int sel_x,
   EndTextureMode();
 }
 
-auto Renderer::DrawMenu(const MassSpringSystem &mass_springs,
-                        int current_preset, const State &current_state,
+auto Renderer::DrawMenu(const std::vector<Mass> &masses,
+                        const std::vector<Spring> &springs, int current_preset,
+                        const State &current_state,
                         const std::unordered_set<State> &winning_states)
     -> void {
   ZoneScoped;
@@ -277,8 +279,7 @@ auto Renderer::DrawMenu(const MassSpringSystem &mass_springs,
 
   draw_btn(0, 0,
            std::format("States: {}, Transitions: {}, Winning: {}",
-                       mass_springs.masses.size(), mass_springs.springs.size(),
-                       winning_states.size()),
+                       masses.size(), springs.size(), winning_states.size()),
            DARKGREEN);
   draw_btn(
       0, 1,

src/state.cpp

@@ -1,8 +1,8 @@
 #include "state.hpp"
-#include "config.hpp"
 #include "presets.hpp"
 #include "tracy.hpp"
 
+#include <mutex>
 #include <raymath.h>
 
 auto StateManager::LoadPreset(int preset) -> void {
@@ -37,31 +37,19 @@ auto StateManager::FillGraph() -> void {
 
   std::pair<std::unordered_set<State>, std::vector<std::pair<State, State>>>
       closure = current_state.Closure();
-  for (const auto &state : closure.first) {
-    mass_springs.AddMass(MASS, false, state);
-  }
-  for (const auto &[from, to] : closure.second) {
-    mass_springs.AddSpring(from, to, SPRING_CONSTANT, DAMPENING_CONSTANT,
-                           REST_LENGTH);
-  }
-  std::cout << "Inserted " << mass_springs.masses.size() << " masses and "
-            << mass_springs.springs.size() << " springs." << std::endl;
+
+  physics.AddMassSpringsCmd(closure.first, closure.second);
+
+  // TODO: We have only dispatched the commands, the states won't be downloaded
+  //       when calling this... Make FindWinningStates() another command?
+  //       Or recalculate whenever masses.size() changes?
   FindWinningStates();
-  std::cout << "Consuming "
-            << sizeof(decltype(*mass_springs.masses.begin())) *
-                   mass_springs.masses.size()
-            << " Bytes for masses." << std::endl;
-  std::cout << "Consuming "
-            << sizeof(decltype(*mass_springs.springs.begin())) *
-                   mass_springs.springs.size()
-            << " Bytes for springs." << std::endl;
 }
 
 auto StateManager::UpdateGraph() -> void {
   if (previous_state != current_state) {
-    mass_springs.AddMass(MASS, false, current_state);
-    mass_springs.AddSpring(current_state, previous_state, SPRING_CONSTANT,
-                           DAMPENING_CONSTANT, REST_LENGTH);
+    physics.AddMassCmd(current_state);
+    physics.AddSpringCmd(current_state, previous_state);
     if (win_conditions[current_preset](current_state)) {
       winning_states.insert(current_state);
     }
@@ -72,8 +60,8 @@ auto StateManager::UpdateGraph() -> void {
 auto StateManager::ClearGraph() -> void {
   winning_states.clear();
   visited_states.clear();
-  mass_springs.Clear();
-  mass_springs.AddMass(MASS, false, current_state);
+  physics.ClearCmd();
+  physics.AddMassCmd(current_state);
 
   // The previous_state is no longer in the graph
   previous_state = current_state;
@@ -84,14 +72,16 @@ auto StateManager::ClearGraph() -> void {
 
 auto StateManager::FindWinningStates() -> void {
   winning_states.clear();
-  for (const auto &[state, mass] : mass_springs.state_masses) {
+  std::unordered_map<State, int> state_masses;
+  {
+    std::lock_guard<LockableBase(std::mutex)> lock(physics.state.pos_mtx);
+    state_masses = physics.state.state_masses;
+  }
+  for (const auto &[state, mass] : state_masses) {
     if (win_conditions[current_preset](state)) {
       winning_states.insert(state);
     }
   }
-
-  std::cout << "Found " << winning_states.size() << " winning states."
-            << std::endl;
 }
 
 auto StateManager::CurrentGenerator() -> StateGenerator {