Re: Short vectors are not plotted

[Dima K. <gn...@di...>]

sfeam <sf...@us...> writes:

> That allows me to test before/after applying 0005 so that I can evaluate
> the intended change by itself.  Here's what I see.
>
> 1) Something has gone wrong with the arrowhead direction.
>     Try running arrowstyle.dem.   All the arrows at the page bottom have
>     inverted arrowheads.
>
> 2) The patch has lost the distinction between "fixed" arrowhead size and
>      the default variable arrowhead size.  Many of the arrows in the
>      arrowstyle demo look strange because their heads are too big.
>
> I attach a revised version of your patch 0005 that addresses 1 + 2.
>
> It adds a parameter to draw_clip_arrow that passes the fixed/variable
> arrowhead size state.  I changed most the call sites to match.
> This change is in patch 0006

Hold on. I don't understand this. What is "fixed"? The docs say ONLY

  By default the size of the arrow head is reduced for very short
  arrows. This can be disabled using the `fixed` keyword after the
  `size` command.

I don't know what that means. A bit of testing with the demo you
mentioned revealed a few bugs with my draw_clip_arrow(). The best one I
have is attached. Note that it doesn't have "fixed" path since I can't
tell what it's supposed to do. If nothing else, the way you implemented
that path suffers from the truncation issue.

With that function, the arrowstyle.dem demo looks "correct", except the
line-through-should-be-empty arrowhead problem you mentioned. Some
arrowheads are shorter than I'd expect, but adding "fixed" to the
arrowstyle in the demo makes it consistent. Is this the "fixed" you're
talking about?