On Thu, Oct 11, 2007 at 04:16:05PM +0800, Yang Zhaohui wrote:
> 
> Hello dir sir,
>     I found some codes as the followed in the scale.js.
> But I donnot know the reason that it is choosen 9500 and 950000 to be the 
> threshold value.What's the meanings of the "K" and "M" ? Are they represeting 
> KiloMeter and Meter?

"Thousand" and "Million".

>     And what's the meaning of ' 1 : getScale()'?

If you don't know the meaning of scale, then it's probably not important
to you. If you do know the meaning of scale, then you know that the
number typically given is a 1:25000 or something similar -- so the
'getScale' function returns the denominator for that. 

>     For example ,referencing the mouse-position example,I make my demo page 
> display pageX,pageY and map coordinates at the same time.When x=3,the map 
> coordinate x=88.86156.And when x=4 ,the map coordinate  x=88.86165.At this 
> time the scale span diaplays "1:27K".Is "1:27K"  representing that
>  one pix in screen is 27 KiloMeters?I am puzzled.Any help will be ok. 
> Thank you very much!

It means that 1 whatever on the screen is one whatever in the real
world: inch to inch, km to km, etc. *if* the screen is 72DPI (or
whatever other DPI value you set). 

If you don't use scale for anything, then it's best just to not worry
about it.

Regards,
-- 
Christopher Schmidt
MetaCarta
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