Abstract. In this paper, we introduce a new method for hatching patient-specific, anatomic 3D surface models, in particular hatching of muscle surfaces. However, the method is transferable to other structures, e. g., , vessels. Since 3D surface models are extracted from binary segmentation masks, the curvature orientation is rough and noisy and the final hatching direction is falsified. The goal of this work is the correction and the completely automated computation of the hatching direction.