Imban said:
Actually, this isn't true of hex-based grids as long as we're constrained to 2D movement. With hexes, any hex Y hexes away is equidistant and you don't have to worry about diagonals. Granted, as soon as flight enters the picture, this stops working quite so well.
I hadn't noticed a problem with Champions Hex Flight.
With regard to distance itself, a simple rule of thumb is: max distance = longer length + 1/3 shorter length for a fair approximation. So, if a target is 100 feet away horizontally and 30 feet up vertically, an approximation is that he is 110 feet away (it's actually 104.4). This is typically good enough, even for Close range calculations.
This "rule of thumb" also works well with hexes if using numbers of hexes instead of feet (for that example, 20 hexes horizontal and 20 hexes vertical is considered 27 hexes away, but is actually closer to 28).
The number comes up a little bit high if the longer distance is much greater than the shorter, a little bit low if the two distances are close to the same. But, it's a good general rule of thumb without doing square and square root calculations in a DM's head.
This rule gets a bit squishy with using number of squares for a square system in any direction except real close to a grid line because the DM cannot just count out the distance in squares unless the target is close to a grid line. Course, for a square system, a DM could change the equation to: longest + 1/3 (x + y) where x and y are the other two dimension distances, but that's more of a pain calculation.
But it works fine for hexes.