Wrp File Format - 4WVR – Talk

note to self via vektorbosen

When trying to view the elevations I realized, that the elevations aren't short values as A-Lone-Wolfs doc implies.

After watching some hex-values, I found some formulas, that should reflect the values right.

w_e: elevations as in 4WVR wrp file f_e: elevations with floating point value

When I create some elevations and want them to convert to Wrp-elevations I'm using the following formula:

w_e = (short) ((f_e / 0.05) * 1.1111)

Ok, when I want to convert them back I am using something like this:

f_e = floor( w_e / 22222.0f ) * 1000 +

      floor( (w_e mod 22222.0f) / 2222.2f ) * 100 + 
     floor( (w_e mod 2222.2f) / 222.22f ) * 10 + a.s.o.

--ook? 13:50, 13 July 2006 (CEST)

This value is an integral of the gridsize.

the gridsize is a fixed 50 metre CUBE. (This is applied equally to XY and Z)

GridDimension= Elevation/50.0

Bis Floats are accurate to 4 decimal places

1.9999 eg

hence the actual value stored only needs the integer and those 4 digits

GridDimension= (short)floor( (Elevation/50)*1000);

ie the 4 important digits are elevated to the integer position of a float. a floor is applied to get ONLY the integer component, and, finally, this is converted (stored) as a genuine short (signed) integer.

The max height or depth of an elevaton is +/- 1.6km