mutable int binding = -1;
const Texture *texture = 0;
const Sampler *sampler = 0;
mutable int binding = -1;
const Texture *texture = 0;
const Sampler *sampler = 0;
void add_shader_data(const ProgramData &data);
void set_texture(Tag, const Texture *, const Sampler * = 0);
void add_shader_data(const ProgramData &data);
void set_texture(Tag, const Texture *, const Sampler * = 0);