• From: DitUnDat@xxxxxxxxx
• To: artworks@xxxxxxxxxxxxx
• Date: Fri, 05 May 2006 15:59:37 +0200

```[snip]

> > Can we have one that ends in an open circle please?
> >
> >  i.e.   o----------o
>
> Thanks for reminding me. Sounds like a good idea. You got it. ;-)
>
> With both the filled and unfilled circles, there remains one question,
> however: Where exactly should they be positioned with respect to the
> line anchor point? It is clear for the old non-integrated arrows - the
> arrowhead starts at the line end, i.e., where the anchor point is. In
> the integrated case, the tip of the arrow is placed on the anchor
> point, but what exactly is the tip of such an arrow? One could argue
> that it is the centre of the blob or the open circle. This would allow
> you to position the centre using the anchor point, which is useful if
> you want to use the filled circle arrowhead to label something.
> Similarly, if you use the open circle arrowhead to denote an open
> interval in a graph, then you will want to position the centre of the
> circle. So, I think this is how it should work.

Well, I think you might want to make it flexible, that is allow for
these anchor points to be considered the arrowhead:

1. the tip is the outside of the circle on the opposite side of the
arrows line so that you can position it so that the circle touches
e.g. some rectangle

2. the tip is the centre of the circle

Perhaps easiest is to define the circle arrowhead twice with one of the
two behaving as 1. and the other as 2.

--
Herbert

Herbert zur Nedden
German Archimedes Group http://www.gag.de

Herausgeber DER deutschen RISC OS-Zeitschrift.

```