Polgon Scan Conversion as a class

hey there, i had my code working without a class, but i need to implement it as a class, and had problems, mainly with what to do with my OpenGL functions such as display, mouse, keyboard, etc, using glut as an interface. If i include them as member functions of the polygon class, the functions are undeclared…if i dont, then the variables in these functions(some are private variables of the class) will be undeclared, im not sure what to do, or how to get it working again.
can someone help me out