feat: added multithreading

include/particle.h

@@ -1,7 +1,10 @@
 #ifndef PARTICLE_H
 #define PARTICLE_H
 
+#include <pthread.h>
 #include <stdlib.h>
+#include <unistd.h>
+#include <stdatomic.h>
 
 #define G_CONSTANT 0.207f
 
@@ -18,9 +21,25 @@ typedef struct {
 	Vec3 velocity;
 	Color color;
 
+	float dampening;
 	float life;
+	float size;
 } Particle;
 
+typedef struct {
+	Particle *particle;
+	unsigned long long thread_id;
+	unsigned long long interval_start;
+	unsigned long long interval_end;
+	int alive_count;
+	float time;
+
+	pthread_mutex_t *mutex;
+	pthread_cond_t *cond;
+	int *barrier;
+	atomic_int exit;
+} Physics_params;
+
 // INFO: This adds adder to out, basicaly out + adder
 void vec_add(Vec3 &out, Vec3 adder) {
 	out.x += adder.x;
@@ -35,6 +54,7 @@ Particle particle_init(Vec3 position, Color color) {
 	p.velocity = {0.0f, 0.0f, 0.0f};
 
 	p.life = 10;
+	p.dampening = 0.97f;
 	return p;
 }
 
@@ -43,19 +63,24 @@ int particle_update(Particle *particles, unsigned long long size, float time) {
 	for (unsigned long long i = 0; i < size; i++) {
 		Particle p = particles[i];
 		if (p.life == 0) {
-			particles[i].position = {0.0f, 0.0f, 0.0f};                        // Start at center
-			particles[i].velocity = {(rand() % 100 - 50) / 50.0f, 5.0f, 0.0f}; // Random spray up
-			particles[i].life = 2.0f;                                          // Give it 2 seconds of life
 			continue;
 		}
 
-		p.velocity.y -= (G_CONSTANT * time);
+		// p.velocity.y -= (G_CONSTANT * time);
 
 		p.position.x += p.velocity.x * time;
 		p.position.y += p.velocity.y * time;
 		p.position.z += p.velocity.z * time;
 
-        if (p.life > 0) p.life -= time;
+		if (p.position.y <= 0) {
+			p.position.y = 0;
+			p.velocity.y *= (-1 * p.dampening);
+		}
+
+		if (p.life > 0)
+			p.life -= time;
+		if (p.life < 0 && p.life >= -1.0f)
+			p.life = 0;
 
 		particles[i] = p;
 		alive_count++;
@@ -64,4 +89,59 @@ int particle_update(Particle *particles, unsigned long long size, float time) {
 	return alive_count;
 }
 
+void *t_update(void *args) {
+	Physics_params *params = (Physics_params *)args;
+	while (params->exit != 1) {
+        pthread_mutex_lock(params->mutex);
+		if (params->(missing) == 0) {
+			sleep(100);
+		}
+        pthread_mutex_unlock(params->mutex);
+
+        params->alive_count = 0;
+		for (unsigned long long i = params->interval_start; i < params->interval_end; i++) {
+			Particle p = params->particle[i];
+
+			if (p.life == 0) {
+				continue;
+			}
+
+			p.velocity.y -= (G_CONSTANT * params->time);
+
+			p.position.x += p.velocity.x * params->time;
+			p.position.y += p.velocity.y * params->time;
+			p.position.z += p.velocity.z * params->time;
+
+			if (p.position.y <= 0) {
+				p.position.y = 0;
+				p.velocity.y *= (-1 * p.dampening);
+			}
+
+			if (p.life > 0)
+				p.life -= params->time;
+			if (p.life < 0 && p.life >= -1.0f)
+				p.life = 0;
+
+			// DEBUG
+			if (params->thread_id == 0) {
+				p.color = {1.0f, 1.0f, 1.0f, 1.0f};
+			} else if (params->thread_id == 1) {
+				p.color = {1.0f, 0.0f, 0.0f, 1.0f};
+			} else if (params->thread_id == 2) {
+				p.color = {0.0f, 1.0f, 0.0f, 1.0f};
+			} else if (params->thread_id == 3) {
+				p.color = {0.0f, 0.0f, 1.0f, 1.0f};
+			} else {
+				p.color = {0.7f, 0.7f, 0.7f, 1.0f};
+				;
+			}
+
+			params->particle[i] = p;
+			params->alive_count++;
+		}
+	}
+
+	return NULL;
+}
+
 #endif // PARTICLE_H