prefabs/typed_prefabs

• C++

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  #include <typed_prefabs.h>
  #include <iostream>
   
  // Just like how entities can be associated with a type (like components) 
  // prefabs can be associated with types as well. Types can be more convenient to
  // work with than entity handles, for a few reasons:
  //
  // - There is no need to pass around or store entity handles
  // - Prefabs automatically assume the name of the type
  // - Nested types can be used to create prefab hierarchies
  //
  // While this functionality is not unique to prefabs (the same mechanism is
  // used to distribute component handles), prefabs are a good fit, especially
  // when combined with prefab hierarchies.
   
  // Create types that mirror the prefab hierarchy.
  struct Turret {
    struct Base {};
    struct Head {};
  };
   
  struct Railgun {
    struct Beam {};
  };
   
  int main() {
      flecs::world ecs;
   
      // Associate types with prefabs
      ecs.prefab<Turret>();
          ecs.prefab<Turret::Base>();
          ecs.prefab<Turret::Head>();
   
      ecs.prefab<Railgun>().is_a<Turret>();
          ecs.prefab<Railgun::Beam>();
   
      // Create prefab instance.
      flecs::entity inst = ecs.entity("my_railgun").is_a<Railgun>();
   
      // Get instantiated children by name
      flecs::entity inst_base = inst.lookup("Base");
      flecs::entity inst_head = inst.lookup("Head");
      flecs::entity inst_beam = inst.lookup("Beam");
   
      std::cout << "instance base: " << inst_base.path() << "\n";
      std::cout << "instance head: " << inst_head.path() << "\n";
      std::cout << "instance beam: " << inst_beam.path() << "\n";
   
      // Output:
      //  instance base: ::my_railgun::Base
      //  instance head: ::my_railgun::Head
      //  instance beam: ::my_railgun::Beam
  }