improved particle system from 90ms to ~ 0.7ms

8 files changed, 92 insertions, 35 deletions

diff --git a/src/crepe/Particle.cpp b/src/crepe/Particle.cpp
index 3254b5b..8cf7f7e 100644
--- a/src/crepe/Particle.cpp
+++ b/src/crepe/Particle.cpp
@@ -1,16 +1,23 @@
 #include "Particle.hpp"
 #include <iostream>
 
-Particle::Particle(float lifespan, Position position, Position velocity)
-    : lifespan(lifespan), position(position), velocity(velocity), timeInLife(0.0f) {}
+Particle::Particle()
+{
+    this->active = false;
+}
+
+void Particle::reset(float lifespan, Position position, Position velocity) {
+    this->timeInLife = 0;
+    this->lifespan = lifespan;
+    this->position = position;
+    this->velocity = velocity;
+    this->active = true;
+}
 
 void Particle::update(float deltaTime) {
     timeInLife += deltaTime;
     position.x += velocity.x * deltaTime;
     position.y += velocity.y * deltaTime;
+    if(timeInLife >= lifespan)this->active = false;
 }
 
-bool Particle::isAlive() const {
-    std::cout << "lifespan" << lifespan << std::endl;
-    return timeInLife < lifespan;
-}
diff --git a/src/crepe/Particle.hpp b/src/crepe/Particle.hpp
index f71fd67..669a8ab 100644
--- a/src/crepe/Particle.hpp
+++ b/src/crepe/Particle.hpp
@@ -1,18 +1,20 @@
 #pragma once
 
-class Particle {
-public:
-    struct Position {
+struct Position {
         float x;
         float y;
     };
 
+class Particle {
+public:
+
     Position position;
     Position velocity;
     float lifespan;
+    bool active;
 
-    Particle(float lifespan, Position position, Position velocity);
+    Particle();
+    void reset(float lifespan, Position position, Position velocity);
     void update(float deltaTime);
-    bool isAlive() const;
     float timeInLife;
 };
diff --git a/src/crepe/ParticleEmitter.cpp b/src/crepe/ParticleEmitter.cpp
index f5c18db..3c9cc4e 100644
--- a/src/crepe/ParticleEmitter.cpp
+++ b/src/crepe/ParticleEmitter.cpp
@@ -1,11 +1,24 @@
 #include "ParticleEmitter.hpp"
 #include <ctime>
+#include "Particle.hpp"
+#include <iostream>
 
 ParticleEmitter::ParticleEmitter(unsigned int maxParticles, unsigned int emissionRate, unsigned int speed, unsigned int speedOffset, unsigned int angle, unsigned int angleOffset, float m_beginLifespan, float m_endLifespan)
     : m_maxParticles(maxParticles), m_emissionRate(emissionRate), m_speed(speed), m_speedOffset(speedOffset), m_position{0, 0}, m_beginLifespan(m_beginLifespan),m_endLifespan(m_endLifespan) {
     std::srand(static_cast<unsigned int>(std::time(nullptr))); // initialize random seed
-
+    std::cout << "Create emitter" << std::endl;
     m_minAngle = (360 + angle - (angleOffset % 360)) % 360; // calculate minAngle
     m_maxAngle = (360 + angle + (angleOffset % 360)) % 360; // calculate maxAngle
+    for (size_t i = 0; i < m_maxParticles; i++)
+    {
+        this->particles.emplace_back();
+    }
+    
+}
 
-}
\ No newline at end of file
+ParticleEmitter::~ParticleEmitter() {
+    std::vector<Particle>::iterator it = this->particles.begin();
+        while (it != this->particles.end()) {
+            it = this->particles.erase(it);
+        }
+}
diff --git a/src/crepe/ParticleEmitter.hpp b/src/crepe/ParticleEmitter.hpp
index f647c27..5de5e1e 100644
--- a/src/crepe/ParticleEmitter.hpp
+++ b/src/crepe/ParticleEmitter.hpp
@@ -3,13 +3,12 @@
 #include <vector>
 #include "Particle.hpp"
 
+
+
 class ParticleEmitter {
 public:
     ParticleEmitter(unsigned int maxParticles, unsigned int emissionRate, unsigned int speed, unsigned int speedOffset, unsigned int angle, unsigned int angleOffset,float m_beginLifespan,float m_endLifespan);
-    struct Position { //struct to hold position
-        float x;
-        float y;
-    };
+    ~ParticleEmitter();
 
     Position m_position; //position of the emitter
     unsigned int m_maxParticles; //maximum number of particles
@@ -22,4 +21,5 @@ public:
     float m_endLifespan; //begin Lifespan of particle
 
     std::vector<Particle> particles; //collection of particles
+
 };
diff --git a/src/crepe/ParticleSystem.cpp b/src/crepe/ParticleSystem.cpp
index f3cb939..aff7a30 100644
--- a/src/crepe/ParticleSystem.cpp
+++ b/src/crepe/ParticleSystem.cpp
@@ -9,30 +9,32 @@
 ParticleSystem::ParticleSystem() : m_elapsedTime(0.0f) {}  // Initialize m_elapsedTime to 0
 
 void ParticleSystem::update(float deltaTime, std::vector<ParticleEmitter>& emitters) {
+    // std::cout << "ParticleSystem update" << std::endl;
     for (ParticleEmitter& emitter : emitters) {
         float updateAmount = 1/static_cast<float>(emitter.m_emissionRate);
         for (float i = 0; i < deltaTime; i += updateAmount)
         {
             emitParticle(emitter);
         }
+        //  std::cout << "after emit" << std::endl;
         
         //update/move particles afterwards delete if not alive.
-        std::vector<Particle>::iterator it = emitter.particles.begin();
-        while (it != emitter.particles.end()) {
-            it->update(deltaTime);
-            if (!it->isAlive()) {
-                it = emitter.particles.erase(it);
-            } else {
-                ++it;
+        for (size_t j = 0; j <  emitter.particles.size(); j++)
+        {
+            // std::cout << "update" << std::endl;
+            if(emitter.particles[j].active)
+            {
+                emitter.particles[j].update(deltaTime);
             }
-        }
+        }     
+
 
     }
 }
 
 void ParticleSystem::emitParticle(ParticleEmitter& emitter) {
     // std::cout << "new emitter:" << std::endl;
-    Particle::Position initialPosition = { emitter.m_position.x, emitter.m_position.y };
+    Position initialPosition = { emitter.m_position.x, emitter.m_position.y };
     float randomAngle = 0.0f;
     //check if value is overthe 360 degrees
     if(emitter.m_maxAngle < emitter.m_minAngle)
@@ -49,11 +51,27 @@ void ParticleSystem::emitParticle(ParticleEmitter& emitter) {
     float randomSpeedOffset = (static_cast<float>(std::rand()) / RAND_MAX) * (2 * emitter.m_speedOffset) - emitter.m_speedOffset;
     float velocityX = (emitter.m_speed + randomSpeedOffset) * std::cos(angleInRadians);
     float velocityY = (emitter.m_speed + randomSpeedOffset) * std::sin(angleInRadians);
-    Particle::Position initialVelocity = {
+    Position initialVelocity = {
         velocityX,
         velocityY
     };
     // std::cout << "emitter.m_endLifespan:" << emitter.m_endLifespan << std::endl;
-
-    emitter.particles.emplace_back(emitter.m_endLifespan, initialPosition, initialVelocity);
+    for (size_t i = 0; i < emitter.particles.size(); i++)
+    {
+        if(!emitter.particles[i].active)
+        {
+            // std::cout << "active " << emitter.particles[i].active << std::endl;
+            // std::cout << "lifespan " << emitter.particles[i].lifespan << std::endl;
+            // std::cout << "timeInLife " << emitter.particles[i].timeInLife << std::endl;
+            // std::cout << "emitter.m_endLifespan" << emitter.m_endLifespan << std::endl;
+            // std::cout << "initialPositionx" << initialPosition.x << std::endl;
+            // std::cout << "initialPositiony" << initialPosition.y << std::endl;
+            // std::cout << "initialVelocityx" << initialVelocity.x << std::endl;
+            // std::cout << "initialVelocityy" << initialVelocity.y << std::endl;
+            emitter.particles[i].reset(emitter.m_endLifespan, initialPosition, initialVelocity);
+            break;
+        }
+    }
+    
+    //emitter.particles.emplace_back(emitter.m_endLifespan, initialPosition, initialVelocity);
 }
diff --git a/src/crepe/SDLApp.cpp b/src/crepe/SDLApp.cpp
index a5e3621..0779af1 100644
--- a/src/crepe/SDLApp.cpp
+++ b/src/crepe/SDLApp.cpp
@@ -1,5 +1,8 @@
 #include "SDLApp.hpp"
 #include <iostream>
+#include <vector>
+#include "Particle.hpp"
+#include "ParticleEmitter.hpp"
 
 SDLApp::SDLApp(int windowWidth, int windowHeight)
     : windowWidth(windowWidth), windowHeight(windowHeight), window(nullptr), renderer(nullptr) {}
@@ -58,6 +61,12 @@ void SDLApp::drawSquare(int x, int y, int size) {
     SDL_RenderFillRect(renderer, &rect);
 }
 
+SDL_Texture* squareTexture = nullptr; // Load this with an image or create it
+
+
+
+
+
 void SDLApp::cleanUp() {
     if (renderer) {
         SDL_DestroyRenderer(renderer);
diff --git a/src/crepe/SDLApp.hpp b/src/crepe/SDLApp.hpp
index 92a4e27..f95d4bc 100644
--- a/src/crepe/SDLApp.hpp
+++ b/src/crepe/SDLApp.hpp
@@ -2,6 +2,8 @@
 #define SDLAPP_HPP
 
 #include <SDL2/SDL.h>
+#include "Particle.hpp"
+#include "ParticleEmitter.hpp"
 
 class SDLApp {
 public:
@@ -14,7 +16,8 @@ public:
     void presentScreen();
     void drawSquare(int x, int y, int size);
     void cleanUp();
-
+    void drawParticles(const std::vector<ParticleEmitter>& emitters);
+    void drawMultipleSquares(const std::vector<SDL_Rect>& squares);
 private:
     int windowWidth;
     int windowHeight;
diff --git a/src/crepe/main.cpp b/src/crepe/main.cpp
index 314dbed..58480a9 100644
--- a/src/crepe/main.cpp
+++ b/src/crepe/main.cpp
@@ -20,7 +20,7 @@ int main(int argc, char* argv[]) {
 
     ParticleSystem particleSystem;
 
-    unsigned int maxParticles = 10;         // maximum number of particles
+    unsigned int maxParticles = 100;         // maximum number of particles
     unsigned int emissionRate = 1;          // particles created per second
     unsigned int speed = 50;                 // base speed of particles
     unsigned int speedOffset = 10;           // random offset for particle speed
@@ -33,7 +33,7 @@ int main(int argc, char* argv[]) {
     std::vector<ParticleEmitter> emitters;
 
     // Loop to create 1000 emitters
-    for (unsigned int i = 0; i < 100; ++i) {
+    for (unsigned int i = 0; i < 1000; ++i) {
         ParticleEmitter emitter(maxParticles, emissionRate, speed, speedOffset, angle, angleOffset, beginLifespan, endLifespan);
         
         // Set a position for each emitter, modifying the position for demonstration
@@ -43,7 +43,7 @@ int main(int argc, char* argv[]) {
     }
     float deltaTime = 0.1f;
     bool running = true;
-
+    std::cout << "start loop " << std::endl;
     while (running) {
         app.handleEvents(running);
 
@@ -59,15 +59,20 @@ int main(int argc, char* argv[]) {
         std::cout << "Update took " << duration.count() << " ms" << std::endl;
         app.clearScreen();
 
+        start = std::chrono::high_resolution_clock::now();
         // render particles using the drawSquare method from SDLApp
         for (const ParticleEmitter& emitter : emitters) {
             for (const Particle& particle : emitter.particles) {
-
-                app.drawSquare(particle.position.x, particle.position.y, 5); // draw each particle
+                if(particle.active)app.drawSquare(particle.position.x, particle.position.y, 5); // draw each particle
             }
         }
+        
 
         app.presentScreen();
+        end = std::chrono::high_resolution_clock::now();
+         duration = end - start; // get duration in milliseconds
+
+        std::cout << "screen took " << duration.count() << " ms" << std::endl;
 
         std::this_thread::sleep_for(std::chrono::milliseconds(20)); // simulate ~50 FPS
     }