asset_factory.h

#pragma once
 
#include <type_traits>
 
#include <nlohmann/json_fwd.hpp>
 
#include "core/reflect.h"
#include "resource/asset/animation_clip_asset.h"
#include "resource/asset/audio_clip_asset.h"
#include "resource/asset/mesh_asset.h"
#include "resource/asset/skeleton_asset.h"
#include "resource/asset/texture_asset.h"
 
namespace Vkm::Engine {
 
class ResourceManager;

template<typename Asset>
using RecipeImport = Handle<Asset> (*)(const nlohmann::json&, ResourceManager&);

struct AssetFactory {
    RecipeImport<MeshAsset>          createMesh          = nullptr;
    RecipeImport<TextureAsset>       createTexture       = nullptr;
    RecipeImport<SkeletonAsset>      createSkeleton      = nullptr;
    RecipeImport<AnimationClipAsset> createAnimationClip = nullptr;
    RecipeImport<AudioClipAsset>     createAudioClip     = nullptr;
};

AssetFactory& assetFactory();

template<typename Asset>
RecipeImport<Asset> recipeImport() {
    const AssetFactory& factory = assetFactory();
    if constexpr (std::is_same_v<Asset, MeshAsset>)               return factory.createMesh;
    else if constexpr (std::is_same_v<Asset, TextureAsset>)       return factory.createTexture;
    else if constexpr (std::is_same_v<Asset, SkeletonAsset>)      return factory.createSkeleton;
    else if constexpr (std::is_same_v<Asset, AnimationClipAsset>) return factory.createAnimationClip;
    else if constexpr (std::is_same_v<Asset, AudioClipAsset>)     return factory.createAudioClip;
    else static_assert(Reflect::DEPENDENT_FALSE<Asset>, "recipeImport: this kind has no import slot");
}
 
} // namespace Vkm::Engine