wip: draw physics thread ups

include/config.hpp

@@ -29,19 +29,17 @@ constexpr float ROT_SPEED = 1.0;
 constexpr float CAMERA_SMOOTH_SPEED = 15.0;
 
 // Physics Engine
-constexpr float SIM_SPEED = 1.0;          // 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
-constexpr float DAMPENING_CONSTANT = 1.0; // Mass spring system
-constexpr float REST_LENGTH = 2.0;        // Mass spring system
-constexpr float VERLET_DAMPENING = 0.05;  // [0, 1]
-constexpr float BH_FORCE = 2.0;           // BH: [1.0, 3.0]
-constexpr float THETA = 1.0;              // Barnes-Hut [0.5, 1.0]
-constexpr float SOFTENING = 0.01;         // Barnes-Hut [0.01, 1.0]
-constexpr float GRID_FORCE = 0.02;        // Grid: [0.0, ~0.05]
-constexpr float REPULSION_RANGE = 5.0 * REST_LENGTH; // Grid
-constexpr int REPULSION_GRID_REFRESH = 5;            // Grid rebuild freq
+constexpr float TARGET_UPS = 90;             // How often to update physics
+constexpr float TIMESTEP = 1.0 / TARGET_UPS; // Update interval in seconds
+constexpr float SIM_SPEED = 4.0;             // How large each update should be
+constexpr float MASS = 1.0;                  // Mass spring system
+constexpr float SPRING_CONSTANT = 5.0;       // Mass spring system
+constexpr float DAMPENING_CONSTANT = 1.0;    // Mass spring system
+constexpr float REST_LENGTH = 2.0;           // Mass spring system
+constexpr float VERLET_DAMPENING = 0.05;     // [0, 1]
+constexpr float BH_FORCE = 2.0;              // Barnes-Hut [1.0, 3.0]
+constexpr float THETA = 0.9;                 // Barnes-Hut [0.5, 1.0]
+constexpr float SOFTENING = 0.01;            // Barnes-Hut [0.01, 1.0]
 
 // Graph Drawing
 constexpr float VERTEX_SIZE = 0.5;

include/physics.hpp

@@ -122,6 +122,7 @@ class ThreadedPhysics {
     TracyLockable(std::mutex, data_mtx);
     std::condition_variable_any data_ready_cnd;
     std::condition_variable_any data_consumed_cnd;
+    unsigned int ups = 0;
     bool data_ready = false;
     bool data_consumed = true;
     std::vector<Vector3> masses; // Read by renderer

include/renderer.hpp

@@ -77,7 +77,7 @@ public:
                 const std::vector<std::pair<std::size_t, std::size_t>> &springs)
       -> void;
 
-  auto DrawTextures() -> void;
+  auto DrawTextures(float ups) -> void;
 };
 
 #endif

src/main.cpp

@@ -44,6 +44,7 @@ auto main(int argc, char *argv[]) -> int {
   OrbitCamera3D camera;
   Renderer renderer(camera, state, input);
 
+  unsigned int ups;
   std::vector<Vector3> masses;                              // Read from physics
   std::vector<std::pair<std::size_t, std::size_t>> springs; // Read from physics
 
@@ -61,6 +62,8 @@ auto main(int argc, char *argv[]) -> int {
     {
       std::unique_lock<LockableBase(std::mutex)> lock(physics.state.data_mtx);
 
+      ups = physics.state.ups;
+
       // Only copy data if any has been produced
       if (physics.state.data_ready) {
         masses = physics.state.masses;
@@ -88,7 +91,7 @@ auto main(int argc, char *argv[]) -> int {
     renderer.DrawMassSprings(masses, springs);
     renderer.DrawKlotski();
     renderer.DrawMenu(masses, springs);
-    renderer.DrawTextures();
+    renderer.DrawTextures(ups);
     FrameMarkEnd("MainThread");
   }
 

src/physics.cpp

@@ -5,8 +5,10 @@
 #include <BS_thread_pool.hpp>
 #include <algorithm>
 #include <cfloat>
+#include <chrono>
 #include <cstddef>
 #include <mutex>
+#include <ratio>
 #include <raylib.h>
 #include <raymath.h>
 #include <tracy/Tracy.hpp>
@@ -190,8 +192,21 @@ auto ThreadedPhysics::PhysicsThread(ThreadedPhysics::PhysicsState &state)
       [&](const struct ClearGraph &cg) { mass_springs.Clear(); },
   };
 
+  std::chrono::time_point last = std::chrono::high_resolution_clock::now();
+  std::chrono::duration<double> accumulator(0);
+  std::chrono::duration<double> update_accumulator(0);
+  unsigned int updates = 0;
+
   while (state.running.load()) {
     FrameMarkStart("PhysicsThread");
+
+    // Time tracking
+    std::chrono::time_point now = std::chrono::high_resolution_clock::now();
+    std::chrono::duration<double> deltatime = now - last;
+    accumulator += deltatime;
+    update_accumulator += deltatime;
+    last = now;
+
     // Handle queued commands
     {
       std::lock_guard<LockableBase(std::mutex)> lock(state.command_mtx);
@@ -208,11 +223,15 @@ auto ThreadedPhysics::PhysicsThread(ThreadedPhysics::PhysicsState &state)
     }
 
     // Physics update
-    // TODO: Respect thread-local deltatime + calculate UPS
-    mass_springs.ClearForces();
-    mass_springs.CalculateSpringForces();
-    mass_springs.CalculateRepulsionForces();
-    mass_springs.VerletUpdate(TIMESTEP * SIM_SPEED);
+    if (accumulator.count() > TIMESTEP) {
+      mass_springs.ClearForces();
+      mass_springs.CalculateSpringForces();
+      mass_springs.CalculateRepulsionForces();
+      mass_springs.VerletUpdate(TIMESTEP * SIM_SPEED);
+
+      ++updates;
+      accumulator -= std::chrono::duration<double>(TIMESTEP);
+    }
 
     // Publish the positions for the renderer (copy)
     FrameMarkStart("PhysicsThreadProduceLock");
@@ -225,6 +244,13 @@ auto ThreadedPhysics::PhysicsThread(ThreadedPhysics::PhysicsState &state)
         break;
       }
 
+      if (update_accumulator.count() > 1.0) {
+        // Update each second
+        state.ups = updates;
+        updates = 0;
+        update_accumulator = std::chrono::duration<double>(0);
+      }
+
       state.masses.clear();
       state.masses.reserve(mass_springs.masses.size());
       for (const auto &mass : mass_springs.masses) {

src/renderer.cpp

@@ -316,7 +316,7 @@ auto Renderer::DrawMenu(
   EndTextureMode();
 }
 
-auto Renderer::DrawTextures() -> void {
+auto Renderer::DrawTextures(float ups) -> void {
   BeginDrawing();
   DrawTextureRec(menu_target.texture,
                  Rectangle(0, 0, menu_target.texture.width,
@@ -330,6 +330,9 @@ auto Renderer::DrawTextures() -> void {
                  Rectangle(0, 0, render_target.texture.width,
                            -1 * render_target.texture.height),
                  Vector2(GetScreenWidth() / 2.0, MENU_HEIGHT), WHITE);
+
   DrawFPS(GetScreenWidth() / 2 + 10, MENU_HEIGHT + 10);
+  DrawText(TextFormat("%.0f UPS", ups), GetScreenWidth() / 2 + 120,
+           MENU_HEIGHT + 10, 20, ORANGE);
   EndDrawing();
 }