From: Phrogz <gavin@...>
Date: 2007-02-08T04:35:08+09:00
Subject: Re: Algorithm Help - Grid Space Calculations

On Feb 7, 12:25 pm, "Martin DeMello" <martindeme...@gmail.com> wrote:
> Here you go:
[snip]
>     ppu = pixel_width / world_width
>     factor = 2 ** lg2(ppu).ceil
>     low = BASE_GRID_SIZE / factor
>     high = low * 2
>     $grid_spacing = ($grid_spacing-high).abs < ($grid_spacing-low).abs ? high : low
[snip]

Excellent, thanks! :)

The logarithm stuff is exactly what was needed (translating it to a
factor in particular). And even though you transcribed into Ruby what
I wrote in English with the "nearest to the current setting"
constraint, for some reason I couldn't come up with it.