main.cpp

#include "Component.hpp"
#include <iostream>

using namespace tdrp;

class ShitComponent : public Component {
public:
  COMPONENT_ENABLE(ShitComponent)

  float x;
};

class PositionComponent : public Component {
public:
  COMPONENT_ENABLE(PositionComponent)

  float x;
  float y;

private:
};

class SpriteComponent : public Component {
public:
  COMPONENT_ENABLE(SpriteComponent) 

  std::string spriteName;
  std::weak_ptr<PositionComponent> m_positionComponent;

  void Initialize(ComponentEntity& owner) override {
    // Ensure co-requisite position component exists
    m_positionComponent = owner.RequireComponent<PositionComponent>();
  };

private:
};

void Move(const ComponentEntity& ent) {
  // Only render things that have a PositionComponent
  ent.IfMatchComponents(
    [] (PositionComponent& position) {
      position.x = 100;
      position.y = 200;
    }
  );
}

void Render(const ComponentEntity& ent) {
  // Only render things that have a SpriteComponent and PositionComponent
  ent.IfMatchComponents(
      [] (SpriteComponent& sprite, PositionComponent& position) {
        std::cout << "I'm rendering " << sprite.spriteName << " at " << position.x << " : " << position.y << std::endl;
      }
  );
}

int main(int argc, char* argv[]) {
  ComponentEntity ent;
  auto spriteComponent = ent.AddComponent<SpriteComponent>();

  {
    spriteComponent.lock()->spriteName = "hey little bitch";
  }

  Move(ent);
  Render(ent);

  return 0;
}