Polygon and line splitting can both cause anomalies in the output.
PSTricks
dash patterns, specified with linestyle=dashed
,
can be disrupted by splitting. This occurs when the depth sort
gives up too early and splits a line where it is not really
necessary.
A workaround is to use gray or finely dotted
lines instead. If your drawing is small, you can also edit the
sketch
output by hand to merge the pieces of the offending
line.
Another anomaly is tiny (or in degenerate cases not-so-tiny) notches
in the lines that border split polygons. These derive from the way
each polygon is painted: first, all pixels within the boundary are
filled with color (perhaps white), then the same boundary is
stroked (a Postscript term) with a line. The result is that
half the line lies inside the boundary and half outside, while the
Painter's algorithm assumes the polygon lies entirely within its
boundary. The notches are due to one polygon fill operation
overwriting the already-drawn inside of the border of another
polygon.1 One workaround is to make
border lines very thin. In fact linewidth=0pt
is guaranteed to
eliminate this problem, though this results in the thinnest line your
output device can draw, which is usually too thin. You might get
lucky by merely reordering things in the input file, which is likely
to move the splits to different places. The only sure-fire solution
is pretty terrible: custom fit special
overlay lines (with
\psline
) to cover the notches.
Polygon splitting also breaks PSTricks
hatch patterns. The
only known workaround is to substitute a solid fill for the hatch.
[1] I know how to fix this problem, but I don't like my solution, and I'm interested in yours.