I have an issue

resource_problem.cpp

class ILoader
{  
public:
	virtual boost::optional<std::string const&> GetParam(std::string const& name) const = 0;
	virtual boost::optional<std::istream> GetDataStream(std::string const& name) = 0;
};

class CSimpleFileLoader :
	public ILoader
{
	std::map<std::string, std::string> Params;

public:
	boost::optional<std::string const&> GetParam(std::string const& name) const override;
	boost::optional<std::istream> GetDataStream(std::string const& name) override;

	explicit CSimpleFileLoader (std::string const& simplePath)
	{
		Params["path"] = simplePath;
	}
};

// THE ACTUAL PROBLEM:
//SOIL_load_OGL_texture_from_memory
//  (
//		image_in_RAM,
//		image_in_RAM_bytes,

std::string CImage::Load(ILoader const& loader)
{
  auto stream = loader.GetDataStream("main");

	m_TexId = SOIL_load_OGL_texture (
  // WAT NOW?