Handling objects with different update frequencies is a common challenge in game development. Here are some strategies to manage this effectively:
Delta Time and Accumulation
Use delta time and accumulate it for each object. When the accumulated time reaches the object's update interval, perform the update.
#include <iostream>
#include <memory>
#include <vector>
class GameObject {
public:
GameObject(float updateInterval) :
updateInterval(updateInterval) {}
virtual void Tick(float deltaTime) {
accumulatedTime += deltaTime;
if (accumulatedTime >= updateInterval) {
Update();
accumulatedTime -= updateInterval;
}
}
virtual void Update() = 0;
private:
float updateInterval;
float accumulatedTime{0};
};
class FastObject : public GameObject {
public:
FastObject() : GameObject(0.016f) {} // 60 FPS
void Update() override {
std::cout << "Fast object updated\n";
}
};
class SlowObject : public GameObject {
public:
SlowObject() : GameObject(1.0f) {} // 1 FPS
void Update() override {
std::cout << "Slow object updated\n";
}
};
int main() {
std::vector<std::unique_ptr<GameObject>>
objects;
objects.push_back(
std::make_unique<FastObject>());
objects.push_back(
std::make_unique<SlowObject>());
float deltaTime = 0.016f; // Assume 60 FPS
for (int frame = 0; frame < 120; ++frame) {
for (auto& obj : objects) {
obj->Tick(deltaTime);
}
}
return 0;
}Update Groups
Group objects by their update frequency and tick each group separately.
class World {
public:
void AddObject(
std::unique_ptr<GameObject> obj,
UpdateFrequency freq) {
switch (freq) {
case UpdateFrequency::EveryFrame:
everyFrameObjects.push_back(
std::move(obj));
break;
case UpdateFrequency::Every10Frames:
every10FramesObjects.push_back(
std::move(obj));
break;
// Add more cases as needed
}
}
void TickAll(int frameCount) {
for (auto& obj : everyFrameObjects) {
obj->Tick();
}
if (frameCount % 10 == 0) {
for (auto& obj : every10FramesObjects) {
obj->Tick();
}
}
// Add more update groups as needed
}
private:
std::vector<std::unique_ptr<GameObject>>
everyFrameObjects;
std::vector<std::unique_ptr<GameObject>>
every10FramesObjects;
};Fixed Timestep
Implement a fixed timestep system that allows objects to update at multiples of a base timestep.
#include <chrono>
#include <thread>
class FixedTimestepWorld {
public:
void Run() {
const double dt = 1.0 / 60.0;
// 60 FPS base timestep
double currentTime = GetTime();
double accumulator = 0.0;
while (true) {
double newTime = GetTime();
double frameTime = newTime - currentTime;
currentTime = newTime;
accumulator += frameTime;
while (accumulator >= dt) {
TickAll(dt);
accumulator -= dt;
}
Render();
}
}
private:
double GetTime() {
using namespace std::chrono;
return duration_cast<duration<double>>(
system_clock::now().time_since_epoch())
.count();
}
void TickAll(double dt) {
for (auto& obj : objects) { obj->Tick(dt); }
}
void Render() {
// Render game objects
}
std::vector<std::unique_ptr<GameObject>> objects;
};These strategies allow you to manage objects with different update frequencies while maintaining a smooth and consistent game loop. Choose the approach that best fits your game's architecture and performance requirements.
Answers to questions are automatically generated and may not have been reviewed.
Ticking
Using Tick() functions to update game objects independently of events
