Sprite it too large.

4096x4096 is probably safe to use these days. I would not use any larger for width or height.

You can use GL_MAX_TEXTURE_SIZE​ to determine the maximum texture size

Code:
	clan::OpenGL::set_active()
	clan::GLint max = 0;
	clan::glGetIntegerv(clan::GL_MAX_TEXTURE_SIZE​ , &max);