Each RAW file is a 601 x 601 square with 6 pixel over lap at each side.
So that is a 589 x 589 active square with the others being a transitional, possibly, read ahead render, type deal.
6 pixels will give the Game Engine 6000 meters to swap renders and such.
Now. Let's look at the RAW file in detail.
The RAW file can ONLY detail the numbers 0 to 255 in Hex. That's 256.
The RAW file does NOT contain COLORS! It contains a number.
That number is HARD CODED to equal a depth. Nothing more.
Now given you have a difference in depth from one pixel to the next?
You get a slope and not a sharp drop. Haven't figured out the slope distance but it can be seen in Game.
Here is an example from in Game of said slope.
Notice the shape angle leading to a DIFFERENCE from Above water to below Water!
Now if one steps the depths down nicely? You'll ping a crap load of different depths as you traverse that difference.
Given I get a hair up my Arse? I could translate SH4 depths from the exported RAW files to a 3D model.
Already done that for SH5 so the very basic code is done and proven.