inline bool is_loaded() const { return loaded; }
inline GLuint get_texture_id() const { return texture_id; }
inline bool is_loaded() const { return loaded; }
inline GLuint get_texture_id() const { return texture_id; }
inline double get_xsize() const { return xsize; }
inline double get_ysize() const { return ysize; }
inline GLfloat *get_ambient() { return ambient; }
inline GLfloat *get_diffuse() { return diffuse; }
inline GLfloat *get_specular() { return specular; }
inline GLfloat *get_emissive() { return emissive; }
inline double get_xsize() const { return xsize; }
inline double get_ysize() const { return ysize; }
inline GLfloat *get_ambient() { return ambient; }
inline GLfloat *get_diffuse() { return diffuse; }
inline GLfloat *get_specular() { return specular; }
inline GLfloat *get_emissive() { return emissive; }