You know the spotted base where the height=0.
I was going through the 3.6 source code and there is:
const DBL HFIELD_OFFSET = 0.001;
This was added and subtracted to the bounding box as well as other things I
haven't chased down.
The point is that if I use a water_line of .001 the spots goes away.
I don't know about other versions. I guess I need to chase them down.
Have Fun!
