feat: Random airfield spawning

src/main.cpp

@@ -9,6 +9,7 @@
 #include "sim/world.hpp"
 #include "sim/aircraft.hpp"
 #include "sim/airfield.hpp"
+#include "sim/af_spawner.hpp"
 
 static SDL_Window *window;
 static SDL_Renderer *sdl_renderer;
@@ -46,7 +47,7 @@ int main(int argc, char *argv[])
 	// World init
 	dxd::sim::World world = dxd::sim::World({ .x = 10, .y = 10 });
 	world.add_obj(new dxd::sim::Aircraft({ 0, 0 }, 1, 5));
-	world.add_obj(new dxd::sim::Airfield({ 15, 0 }));
+	world.add_obj(new dxd::sim::AFSpawner());
 
 	SDL_Event event;
 	bool running = true;

src/renderer.hpp

@@ -47,7 +47,7 @@ public:
 	Renderer(SDL_Renderer *sdl, int width, int height) : _sdl(sdl), _width(width), _height(height)
 	{
 		_center = { 0, 0 };
-		_scale = 0.02;
+		_scale = 0.01;
 	}
 
 	void move_camera(vec2 delta)

src/sim/af_spawner.cpp

@@ -0,0 +1,17 @@
+#include "af_spawner.hpp"
+
+void dxd::sim::AFSpawner::tick(float timestep, World *world)
+{
+	++_cur_tick;
+
+	if (_cur_tick < _next_spawn)
+		return;
+
+	_next_spawn = _cur_tick + 60 + SDL_rand(120);
+
+	//Pos should spawn in a grid, check if free, and offset random from grid coord to look natural
+	vec2 pos = {(SDL_randf()-.5f)*2*60.0f, (SDL_randf()-.5f)*2*60.0f};
+	Airfield *af = new Airfield(pos, 180 + SDL_rand(600));
+	world->add_obj(af);
+	_airfields.push_back(af);
+}

src/sim/af_spawner.hpp

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <vector>
+
+#include "../math.hpp"
+#include "world_object.hpp"
+#include "airfield.hpp"
+
+namespace dxd::sim
+{
+
+class AFSpawner : public WorldObject
+{
+private:
+	std::vector<Airfield*> _airfields;
+	int _cur_tick;
+	int _next_spawn;
+
+public:
+	AFSpawner()
+	{
+		_airfields = std::vector<Airfield*>();
+		_cur_tick = _next_spawn = 0;
+	}
+
+	void tick(float timestep, World *world) override;
+	void draw(Renderer *rend) override {}
+};
+
+} // namespace dxd::sim

src/sim/aircraft.cpp

@@ -1,6 +1,6 @@
 #include "aircraft.hpp"
 
-void dxd::sim::Aircraft::tick(float timestep, vec2 bounds)
+void dxd::sim::Aircraft::tick(float timestep, World *world)
 {
 	_position = _position + polar_to_vec2(_direction, _speed) * timestep;
 }

src/sim/aircraft.hpp

@@ -17,7 +17,7 @@ public:
 	Aircraft(vec2 position, float direction, float speed)
 		: _position(position), _direction(direction), _speed(speed) {}
 
-	void tick(float timestep, vec2 bounds) override;
+	void tick(float timestep, World *world) override;
 	void draw(Renderer *rend) override;
 };
 

src/sim/airfield.cpp

@@ -1,8 +1,9 @@
 #include "airfield.hpp"
 
-void dxd::sim::Airfield::tick(float timestep, vec2 bounds)
+void dxd::sim::Airfield::tick(float timestep, World *world)
 {
-
+	if (--_ttl == 0)
+		world->remove_obj(this);
 }
 
 void dxd::sim::Airfield::draw(Renderer *rend)

src/sim/airfield.hpp

@@ -12,11 +12,12 @@ class Airfield : public WorldObject
 {
 private:
 	vec2 _position;
+	int _ttl;
 
 public:
-	Airfield(vec2 position) : _position(position) {}
+	Airfield(vec2 position, int ttl) : _position(position), _ttl(ttl) {}
 
-	void tick(float timestep, vec2 bounds) override;
+	void tick(float timestep, World *world) override;
 	void draw(Renderer *rend) override;
 };
 

src/sim/world.cpp

@@ -4,7 +4,7 @@ void dxd::sim::World::tick(float timestep)
 {
 	for (auto obj : _objs)
 	{
-		obj->tick(timestep, _size);
+		obj->tick(timestep, this);
 	}
 }
 

src/sim/world.hpp

@@ -8,6 +8,8 @@
 namespace dxd::sim
 {
 
+class WorldObject;
+
 class World
 {
 private:
@@ -21,6 +23,17 @@ public:
 	}
 
 	void add_obj(WorldObject *obj) { _objs.push_back(obj); }
+	void remove_obj(WorldObject *obj)
+	{
+		for (auto it = _objs.begin(); it != _objs.end(); ++it)
+		{
+			if (*it == obj)
+			{
+				_objs.erase(it);
+				break;
+			}
+		}
+	}
 
 	void tick(float timestep);
 	void draw(Renderer *rend);

src/sim/world_object.hpp

@@ -2,16 +2,19 @@
 
 #include "../math.hpp"
 #include "../renderer.hpp"
+#include "world.hpp"
 
 namespace dxd::sim
 {
 
+class World;
+
 class WorldObject
 {
 public:
 	WorldObject() {}
 
-	virtual void tick(float timestep, vec2 bounds) = 0;
+	virtual void tick(float timestep, World *world) = 0;
 	virtual void draw(Renderer *rend) = 0;
 };