Realistic representation of various effects which are appeared in the real world paintings can be used for several applications like as animation or education. To generate Oriental paintings, numerous studies have focused on model-based approaches. In this paper, a new model-based approach for Oriental paintings is described. To represent the diffusion effects, we propose local equilibrium model (LEM) which is a method to calculate the movement of water and ink effectively. In addition, we propose a paper model with fiber mesh structure and three layers structure on each cell. With this layer model, overlapped strokes can be well represented. A brush model proposed supports several brush effects like as shading.