packCover

The channels as bytes, in the order the vertex attributes carry them: the first four in terrainCover, the second four in terrainCover2.

Math.round rather than a truncating multiply, because the ends have to survive: a cover of exactly 1 truncated by value * 255 | 0 is 255 only if the multiply lands on it, and a 254 where the field says "wholly ice" is a one-part-in-255 seam wherever a fully covered patch meets one that rounded the other way.

The last two bytes are written as zero and read by nothing. A vertex buffer stride has to be a multiple of four, so six channels cost eight bytes whatever is put in them, and the two spare are where the canonical slope the deposits still want will go.

coverSurfaceCover

Undocumented

outUint8Array

Undocumented

atnumber

Undocumented