Re: Argh: Why are arrows clipped to the graph?

[Harald H. <h.h...@tu...>]

On Fri, 11 Nov 2005, Daniel J Sebald wrote:

> > set size 2,2
> > set terminal png
> > set output 'asdf.png'
> > plot sin(x)
> > set output
> >
> > Have of the tic marks are missing.

sed s/Have/Half/.

> Hmm.  Not right of course, but this seems as though it may be a
> different bug.  I see all the tic marks, but the annotation is what is
> missing.

That's what I meant. It's easy: All text that is requested with a screen
coordinate above 1 is not printed. It does not have to do with negative or
positive numbers. Just try another size than 2,2.

> >>Also, write a nicer do_arrow(), as Ethan suggests.  I think I could do
> >>it fairly easily, but I simply don't have time now.  It would have to
> >>wait until after the holidays.
> >
> > What do you want to improve? For me, the Postscript arrows are good
> > enough.
>
> I'd thought I'd read in the thread somewhere that better PostScript
> arrows clipped at the edge of the canvas were desired.  Sorry.

If the line and the filled-path code supports correct clipping and the
original arrow code uses these clipped lines and filled paths,
parly clipping of arrow heads will be supported by every terminal.

For postscript of course, no clipping code will be necessary at all:

%!PS-Adobe-2.0 EPSF-2.0
%%BoundingBox: 0 0 100 100
%%EndProlog
gsave
% Introduce clipping
newpath
30 30 moveto
70 30 lineto
70 70 lineto
30 70 lineto
closepath
clip
% Some tests
newpath
1 0 0 setrgbcolor
0 0 moveto
100 100 lineto
stroke
10 50 moveto
(Times-Roman) findfont 10 scalefont setfont
(Hello world, this is clipped) show
% Remove clipping again
grestore
showpage
%%Trailer


> > Yes, of course. Postscript can do nearly everything except translucent
> > objects.
>
> (Really?  I'd been guessing, or hoping, it would.  Oh well.)

Maybe it can't cook coffee.

Best regards
Harald

-- 
Harald Harders
h.h...@tu...
http://www.harald-harders.de