To get rid of the limitations of a real sand table which is not portable and has high professional requirements of sand painting techniques, also to enhance the naturalness and interest of users' experience, an algorithm of colored sand painting simulation is proposed. The algorithm consists of two main parts: (1) Colored sand painting generation method. It uses HSV and RGB models to express color information. When sand of different colors are piled up, under the influence of the light from the bottom of the sand table, the color of the pixels depend on the light transmission, that is light reflectivity among thick multi-layer sand. (2) Detail processing method. It takes advantages of principle of mass conservation to simulate the sand transfer process and random perturbations for various realistic painting techniques. Besides those above, our simulation system supports multi-touch process on a multi-touch device served as a sand table. The experimental results indicate that our algorithm can not only present technique details in a realistic, effective, and real-time manner, but also simulate several interactive modes of colored sand painting with fine details in a multi-touch device.

colored sand painting, overlay strategy, rendering efficiency, detail processing, multi-touch.