The hierarchical Poisson disk sampling technique is one of the most powerful NPR techniques to generate watercolor painting images from input images. It can generate various kinds of watercolor painting images by varying parameter values according to user's preferences. However, the hierarchical Poisson disk sampling technique has a weak point that it takes long time. We have developed a fast hierarchical Poisson disk sampling technique by using pre-sampled data. We also realized a fast stroke drawing technique by space sub-division.
