little_helpers/tikz/sketch-0.2.161/Doc/sketch/Limits-on-error-detection.html

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  56 <h4 class="subsection">4.4.1 Limits on <code>sketch</code> error detection</h4>
  57
  58 <p><code>Sketch</code> catches many kinds of errors, but not all. For example,
  59 options that sketch does not recognize, even incorrect ones, are
  60 quietly copied to <code>PSTricks</code> commands in the output.  It is also
  61 unfortunately easy to produce <code>sketch</code> inputs that lead to no
  62 picture at all (improper vertex ordering causes everything to be
  63 culled), to pictures that are too big or too small for <code>PSTricks</code>
  64 to draw (due to limits of TeX math), and pictures that look nothing
  65 like what was intended.  A picture with one of these problems can be
  66 difficult to &ldquo;debug.&rdquo;  We offer the following suggestions.
  67      <ul>
  68 <li>Follow the suggested incremental development method described in
  69 <a href="Overview.html#Overview">Overview</a>.
  70 <li>Always maintain one or two back-versions of a drawing so that it is
  71 easy to fall back to a known-good increment.
  72 <li>When using <code>perspective</code>, ensure all finally transformed objects
  73 satisfy z&lt;0 and, in fact, do not come very close to the origin
  74 at all.
  75 <li>Temporarily use <code>cull=false</code> to see where vertex ordering
  76 problems lie.
  77 <li>Use temporary changes of color of one or more objects to ensure that
  78 your understanding of the scene geometry is correct.
  79 <li>If <code>PSTricks</code> complains about something, inspect the output
  80 directly for clues.
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