Smooth surfaces, to some of us who religiously do Feature Tracked 3D Camera solves, they are the Devil. Unless the smooth suface has pours that we can boost the contrast on, its pretty hard to track those suckers. Something that Planar tracking seems to Excel at. By Planar Tracking a smooth surface suddenly allows you to recreate the shot to have a texture on top of the of this surface, But what should you put on it? A gird would seem to work out great..since it would allow a high density of trackers constantly distributed over the surface, In theory its sounds good. Yet Grids are too similar for the tracker algorithm, which bumps up the computational time to figure out which grid square a track as well as confusing the features to jump from square to square with in the search region a set back that often cant be avoided if the track is moving a significant distance. So what to do? An Irregular Texture turns out to be just what the doctor ordered. Perln Factual Noise is a fast way to generate a texture on the fly And complimentes most trackers search algorithms natural ability to look for high contrast patterns through out the enhanced plate.
The Exeption: Optical Flow tracking
Where contrast based Feature tracking gets confused and dazed at a black and white checkers Optical flow behaves different and tracks through less of an issue though it will get tripped a bit.