[NTG-context] Extending the black circled numbers

[nico]

On Tue, 04 Apr 2006 14:44:28 +0200, Hans Hagen <pragma at wxs.nl> wrote:

> nico wrote:
>> Hello,
>>
>> Typically the numbers are rendered white in black
>> circle. I could use the Dingbats numbers, but it is limited to 10, so  
>> that
>> I emulated them with the following code to be able to go up to 99.
>>
>> The questions I have:
>> - Is it the right way to do it in context (do I really need metafont?
>> Simpler, smarter method?)

> \setupcolors[state=start]
>
> \startuniqueMPgraphic{CoCircle}
>    fill fullcircle xysized (OverlayWidth,OverlayHeight) withcolor  
> OverlayColor ;
> \stopuniqueMPgraphic

I see here the Hans touch again: it's better and I don't really understand  
how it works :-)
But there's something strange: the first circle is greater than the others  
(but the numbers have all the same size). Tracing a bit I see that the  
first circle has a width=16.5333pt, the others 13.19997pt. What's the  
reason for this?

Thanks much!

Regards,
BG