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Oscar,<br>
<br>
This is an email I found in my email archive, that might help you with
your lines.<br>
<br>
Frank<br>
<br>
**********<br>
<br>
<br>
<div class="gmail_quote">On Fri, Jul 17, 2009 at 3:17 AM, Dhaval
Prajapati <span dir="ltr"><<a
href="mailto:dhaval.prajapati@iccsir.org">dhaval.prajapati@iccsir.org</a>></span>
wrote:<br>
<blockquote class="gmail_quote"
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div bgcolor="#ffffff">
<div><font face="Verdana" size="4"> Hi,<br>
<br>
I have prepared . ps files using grads. Now in the file there are
horizontal lines coming for colors <br>
</font><font face="Verdana" size="4">How to remove it?<br>
is there any command to get batter images?<br>
</font><font face="Verdana" size="2"><font size="4">I am attaching
one file for sample in both .ps and .jpg format</font></font></div>
</div>
</blockquote>
<div><br>
</div>
<div><br>
</div>
<div>Try "gxyat" that comes with the opengrads bundle (available from <a
href="http://opengrads.org">http://opengrads.org</a>). Basically,
gxyat is a replacement for "printim", although it can produce .ps, .pdf
and .svg output. More info here:</div>
<div><br>
</div>
<div> <a href="http://opengrads.org/wiki/index.php?title=Gxyat">http://opengrads.org/wiki/index.php?title=Gxyat</a></div>
<div><br>
</div>
<div>Some remarks on these "lines":</div>
<div><br>
</div>
<div>1) The "lines" you are referring do not appear if you print your
postscript file on paper, only on the screen. These "lines" come from
an artifact of the grads shading algorithm and the anti-aliasing
algorithm used by the programs that display postscript on the screen.
However, depending on your display program, sometimes you can turn
anti-aliasing off and the lines go way. However, the fonts do not look
as good.</div>
<div><br>
</div>
<div>2) When you convert your postscript to jpg,
anti-aliasing is usually applied and you get the "lines". Again,
depending on your conversion program you can turn anti-aliasing off and
get rid of the "lines" at the expense of jagged fonts.</div>
<div><br>
</div>
<div>3) What "gxyat" does when creating image files
(.png in this case) is to use anti-aliasing when drawing lines and turn
anti-aliasing off when doing polygon fills. In the end you get smooth
fonts and no "lines". In addition, "gxyat" gives you a lot more
flexibility with transparency.</div>
<div><br>
</div>
<div>4) If you write .ps/.pdf files with gxyat you will
have the same problem with the "lines". The reason is that there is no
way (that I know of) in postscript to turn anti-aliasing on/off for
part of a page, it is all or nothing.</div>
<div><br>
</div>
<div>BTW, you can use "gxyat" from the grads command line (replacement
for "printim"):</div>
<div><br>
</div>
<div>ga-> gxyat image.png</div>
<div><br>
</div>
<div>or from the OS command line (replacement for gxpng, gxeps):</div>
<div><br>
</div>
<div>$ gxyat -o image.png image.gmf</div>
<div><br>
</div>
<div>where
"image.gmf" is a grads metafile. The SVG output is very useful to
import grads output into vector graphics programs such as Adobe
Illustrator or Inkscape without loosing any resolution (great for
posters).</div>
<div><br>
</div>
<div>It would be great if someone could contribute a recipe to the
Cookbooks illustrating these points.</div>
<div><br>
</div>
<div> Arlindo</div>
<div><br>
</div>
<div><br>
</div>
</div>
-- <br>
Arlindo da Silva<br>
<a href="mailto:dasilva@alum.mit.edu">dasilva@alum.mit.edu</a><br>
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