[metapost] defaultcolormodel

[Stephan Hennig]

schrieb luigi scarso:
> 2011/7/8 Karel <akk64 at quick.cz>:
>> Taco Hoekwater napsal(a):
>>>
>>> On 07/08/2011 12:01 AM, Stephan Hennig wrote:
>>>>
>>>> Well, variable defaultcolormodel determines the colour space of the
>>>> black ink that is used for drawing and filling strokes, i.e., whether 0,
>>>> (0,0,0) or (0,0,0,1) is written into the output.
>>>
>>> Yes.
>>>
>>
>> I think it is not the case. I tried
>>
>> defaultcolormodel:=3;
>>
>> beginfig(0);
>> defaultcolormodel:=3;
>> draw fullcircle scaled 10mm withcolor .5white;
>> endfig;

There must be some colour to output anything even if no withcolor
statement is given (including drawoptions).  Think about MetaFont that
has no notion of colours, yet it has to distinguish between pixels that
have been touched by a pen and those that haven't in the output.  This
'implicit' black is what defaultcolormodel refers to (and what I meant
by 'black ink').

Best regards,
Stephan Hennig