Spot noise is a technique for texture synthesis, which is very useful for vector field visualization. This paper describes improvements and extensions of the basic principle of spot noise. First, better visualization of highly curved vector fields with spot noise is achieved, by adapting the shape of the spots to the local velocity field. Second, filtering of spots is proposed to eliminate undesired low frequency components from the spot noise texture. Third, methods are described to utilize graphics hardware to generate the texture, and to produce variable viewpoint animations of spot noise on surfaces. And fourth, the synthesis of spot noise on grids with highly irregular cell sizes is described.