merge `jaro/particle-system-master` into `loek/cleanup` early

1 files changed, 53 insertions, 11 deletions

diff --git a/src/crepe/Particle.h b/src/crepe/Particle.h
index 21e691d..8782382 100644
--- a/src/crepe/Particle.h
+++ b/src/crepe/Particle.h
@@ -1,22 +1,64 @@
 #pragma once
 
-#include "Position.h"
+#include <cstdint>
+
+#include "api/Vector2.h"
 
 namespace crepe {
 
+/**
+ * \brief Represents a particle in the particle emitter.
+ *
+ * This class stores information about a single particle, including its position,
+ * velocity, lifespan, and other properties. Particles can be updated over time
+ * to simulate movement and can also be reset or stopped.
+ */
 class Particle {
+	// TODO: add friend particleSsytem and rendersystem. Unit test will fail.
+
 public:
-	Position position;
-	// FIXME: `Position` is an awkward name for a 2D vector. See FIXME comment in
-	// api/Transform.h for fix proposal.
-	Position velocity;
-	float lifespan;
-	bool active;
+	//! Position of the particle in 2D space.
+	Vector2 position;
+	//! Velocity vector indicating the speed and direction of the particle.
+	Vector2 velocity;
+	//! Accumulated force affecting the particle over time.
+	Vector2 force_over_time;
+	//! Total lifespan of the particle in milliseconds.
+	uint32_t lifespan;
+	//! Active state of the particle; true if it is in use, false otherwise.
+	bool active = false;
+	//! The time the particle has been alive, in milliseconds.
+	uint32_t time_in_life = 0;
+	//! The angle at which the particle is oriented or moving.
+	double angle = 0;
 
-	Particle();
-	void reset(float lifespan, Position position, Position velocity);
-	void update(float deltaTime);
-	float time_in_life;
+	/**
+	 * \brief Resets the particle with new properties.
+	 *
+	 * This method initializes the particle with a specific lifespan, position,
+	 * velocity, and angle, marking it as active and resetting its life counter.
+	 *
+	 * \param lifespan  The lifespan of the particle in amount of updates.
+	 * \param position  The starting position of the particle.
+	 * \param velocity  The initial velocity of the particle.
+	 * \param angle     The angle of the particle's trajectory or orientation.
+	 */
+	void reset(uint32_t lifespan, const Vector2& position,const Vector2& velocity,
+			   double angle);
+	/**
+	 * \brief Updates the particle's state.
+	 *
+	 * Advances the particle's position based on its velocity and applies accumulated forces. 
+	 * Deactivates the particle if its lifespan has expired.
+	 */
+	void update();
+	/**
+	 * \brief Stops the particle's movement.
+	 *
+	 * Sets the particle's velocity to zero, effectively halting any further
+	 * movement.
+	 */
+	void stop_movement();
 };
 
 } // namespace crepe