Survey of nonphotorealistic rendering (npr) for computer graphics and animation painterly rendering, toon shading, painterly image processing, and simulation of .Had this problem for few weeks. check your blade for residue and errant bits of material. ensure the cap is completely screwed on, it can come loose. Decorating your front door or outside area for halloween can be lot of fun. coming up with creative ways to frighten people coming to your door on halloween night .