我想从一个Lua脚本加载纹理到我的C++游戏引擎。从Lua传递枚举类型到C++的最简单方法?
引擎使用一个名为“ResourceHolder”的类,枚举类型来自一个名为“ResourceIdenifiers”的类。
我的游戏场景为纹理创建了自己的ResourceHolder &字体(以及我需要的任何其他东西)。所以我有用于Textures :: ID(枚举类型)和字体:: ID的名称空间。
所以我只需创建一个TextureHolder对象mTextures“
TextureHolder mTextures;
然后,我只是加载很容易的纹理有烧灼线像这样:
mTextures.load(Textures::Airplane2, "../GFX/Airplane2.png");
的问题是,我不能在Lua中使用这些枚举类型,尽管我的计划是在我的lua.script文件中有这样的东西:
allTextures
{
--Airplanes
["Airplane1"] = "../GFX/Airplane1.png",
["Airplane2"] = "../GFX/Airplane2.png",
--Or something like this instead
["Textures::Airplane3"] = "../GFX/Airplane3.png"
}
允许Lua脚本处理这些枚举类型的最简单方法是什么?
这里是我的ResourceIdentifier和ResourceHolder的类。
ResourceIdentifier.h
#ifndef RESOURCEIDENTIFIERS_H
#define RESOURCEIDENTIFIERS_H
// Forward declaration of SFML classes
namespace sf
{
class Texture;
class Font;
}
namespace Textures
{
enum ID
{
//Airplanes
Airplane1,
Airplane2,
Airplane3,
Background1,
Background2,
};
}
namespace Fonts
{
enum ID
{
Main,
};
}
// Forward declaration and a few type definitions
template <typename Resource, typename Identifier>
class ResourceHolder;
typedef ResourceHolder<sf::Texture, Textures::ID> TextureHolder;
typedef ResourceHolder<sf::Font, Fonts::ID> FontHolder;
#endif // RESOURCEIDENTIFIERS_H
ResourceHolder.h(不太相关)
#ifndef RESOURCEHOLDER_H
#define RESOURCEHOLDER_H
#include <map>
#include <string>
#include <memory>
#include <stdexcept>
#include <cassert>
#include <SFML/Graphics/Image.hpp>
template <typename Resource, typename Identifier>
//This class stores Identifier so they can be accessed.
class ResourceHolder
{
public:
//This creates loads the texture from the filename, gives it an ID, and stores it in the std::map container mTextureMap.
void load(Identifier id, const std::string& filename);
void loadImage(Identifier id, const sf::Image& image);
template <typename Parameter>
void load(Identifier id, const std::string& filename, const Parameter& secondParam);
//This gets the texture from the std::map container, so it can be used. It gets the Resource based on the texture's ID (name).
Resource& get(Identifier id);
const Resource& get(Identifier id) const;
//^SFML book - Chapter 2 - "Accessing the Identifier" ??? For when you dont want to allow editing of the Texture???
private:
//A map stores all of the Identifier. The std::map< (1 parameter) 'Name of Resource', (2 parameter) a unique pointer of the Resource).
std::map<Identifier, std::unique_ptr<Resource> > mResourceMap;
};
#include "ResourceHolder.inl"
#endif // RESOURCEHOLDER_H