Abstract: Aim at the lacks of effective integral anti-aliased algorithm to generate circle and ellipse, using modified midpoint generating algorithm, a unified algorithm completely using integer operation to realized pixel level anti-aliased line, circle and ellipse is presented. According to the error control parameter of midpoint algorithm, the new algorithm calculated the accurate distance between candidate point and idea curves, abandoned the higher-order epsilon with litter effect, and used looking-up table or range bisection method to determine the lightness of the nearest pixel. This algorithm only modified part of the original algorithm and inherited its simple structure. Furthermore, due to the only use of integer operation, the algorithm can generate smooth line, circle and ellipse rapidly and is also convenient for hardware implementation. The proposed algorithm not only provided a fast integral approach to draw anti-aliased curves, but also made the basic graphs and the anti-aliased to be easily generated under the same framework.