public:
void attach(FramebufferAttachment attch, Renderbuffer &rbuf);
void attach(FramebufferAttachment attch, Texture2D &tex, unsigned level = 0);
public:
void attach(FramebufferAttachment attch, Renderbuffer &rbuf);
void attach(FramebufferAttachment attch, Texture2D &tex, unsigned level = 0);