[NTG-context] Metafun: how to draw a straight line past the end points

[Otared Kavian]

Hi Fabrice,

Thanks a lot ! Indeed that does the job, which shows how wonderful Metafun is !

Best regards: Otared

> On 9 Dec 2020, at 17:19, Fabrice L <fabrice.alpha at gmail.com> wrote:
> 
> Hi,
> 
>> Le 9 déc. 2020 à 10:57, Otared Kavian <otared at gmail.com> a écrit :
>> 
>> Hi,
>> 
>> I have a silly question: given two points in the plane
>> 	z1 = (1cm,3cm) ;
>> 	z2 = (5cm, 9cm) ;
>> the command
>> 	draw z1 -- z2 withpen pencircle scaled .5pt ;
>> draws the line segment joining z1 and z2. How could I draw the line segment which goes a little further (say 1cm) than both the end points of this segment (that is in this example, a point before z1 and a point after z2 on the straight line) .
>> Indeed it is possible to write the equation of the line and then compute by hand the coordinates of the new end points, but I think there is a simpler way in Metafun to do this.
> 
> The shortened operation is the solution ! See MetaFun manual section 1.18
> 
> \starttext
> \startMPpage
> z1 = (1cm,3cm) ;
> z2 = (5cm, 9cm) ;
> draw (z1--z2) shortened -1cm  withcolor blue ;
> draw (z1--z2) withcolor red ;
> 
> \stopMPpage
> \stoptext
> 	
> Fabrice.
> 
>> 
>> Thanks for any help: Otared
>> 
>> 
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> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to the Wiki!
> 
> maillist : ntg-context at ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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