For anyone interested in the game mechanics used I just tonight updated to correct a glitch in the game and at the same time make it more realistic. I was 'dropping' mines at about half the depth of the ocean. At that depth the player could actually motor past them in the water column. Not very realistic. The reason for this was because of the ocean floor contours which were pre-made and just loaded as 3 different scenes the game level generator chooses from.
This turned out to not be too difficult to fix; it involved using a linear function on the one ocean floor which present problems. The mines are dropped just above the ocean floor at a height that changes based on the global x-position of the mine to be placed. Then game physics does the rest.
The other two ocean profiles are flat enough that a simple adjustment to the proper height above the floor fixed those.
I had a similar problem with the DISSUB - I was dropping it too low and it was spawning going through the tilemap ocean floor!
