component_getter.h

#pragma once
#include "gaia/config/config.h"
 
#include <cstdint>
 
#include "gaia/ecs/chunk.h"
#include "gaia/ecs/component.h"
 
namespace gaia {
  namespace ecs {
    class World;
 
    struct ComponentGetter {
      const World* m_pWorld;
      const Chunk* m_pChunk;
      Entity m_entity;
      uint16_t m_row;
 
      ComponentGetter(const World& world, const Chunk* pChunk, Entity entity, uint16_t row):
          m_pWorld(&world), m_pChunk(pChunk), m_entity(entity), m_row(row) {}
 
      template <typename T>
      GAIA_NODISCARD decltype(auto) get() const {
        GAIA_ASSERT(m_pWorld != nullptr);
        GAIA_ASSERT(m_entity != EntityBad);
        GAIA_ASSERT(m_pChunk != nullptr);
        verify_comp<T>();
 
        if constexpr (entity_kind_v<T> == EntityKind::EK_Gen)
          return m_pChunk->template get<T>(m_row);
        else
          return m_pChunk->template get<T>();
      }
 
      template <typename T>
      GAIA_NODISCARD decltype(auto) get(Entity type) const;
    };
  } // namespace ecs
} // namespace gaia