little_helpers/tikz/sketch-0.2.161/Doc/sketch/Bugs-and-anomalies.html

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  54 <h5 class="subsubsection">4.4.3.2 Bugs and anomalies</h5>
  55
  56 <p>Polygon and line splitting can both cause anomalies in the output.
  57 <code>PSTricks</code> dash patterns, specified with <code>linestyle=dashed</code>,
  58 <a name="index-linestyle-504"></a>can be disrupted by splitting.  This occurs when the depth sort
  59 <a name="index-depth-sort-505"></a>gives up too early and splits a line where it is not really
  60 necessary.
  61 A workaround is to use gray or finely dotted
  62 lines instead.  If your drawing is small, you can also edit the
  63 <code>sketch</code> output by hand to merge the pieces of the offending
  64 line.
  65
  66    <p>Another anomaly is tiny (or in degenerate cases not-so-tiny) notches
  67 in the lines that border split polygons.  These derive from the way
  68 each polygon is painted: first, all pixels within the boundary are
  69 <dfn>filled</dfn> with color (perhaps white), then the same boundary is
  70 <dfn>stroked</dfn> (a Postscript term) with a line.  The result is that
  71 half the line lies inside the boundary and half outside, while the
  72 Painter's algorithm assumes the polygon lies entirely within its
  73 boundary.  The notches are due to one polygon fill operation
  74 overwriting the already-drawn inside of the border of another
  75 polygon.<a rel="footnote" href="#fn-1" name="fnd-1"><sup>1</sup></a>  One workaround is to make
  76 border lines very thin.  In fact <code>linewidth=0pt</code> is guaranteed to
  77 eliminate this problem, though this results in the thinnest line your
  78 output device can draw, which is usually too thin.  You might get
  79 lucky by merely reordering things in the input file, which is likely
  80 to move the splits to different places.  The only sure-fire solution
  81 is pretty terrible: custom fit <code>special</code> overlay lines (with
  82 <code>\psline</code>) to cover the notches.
  83
  84    <p>Polygon splitting also breaks <code>PSTricks</code> hatch patterns.  The
  85 only known workaround is to substitute a solid fill for the hatch.
  86
  87    <div class="footnote">
  88 <hr>
  89 <h4>Footnotes</h4><p class="footnote"><small>[<a name="fn-1" href="#fnd-1">1</a>]</small> I know how to fix this problem, but I don't like my
  90 solution, and I'm interested in yours.</p>
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