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Comment:In the GeoPoly documentation, mention that geopoly_ccw() can be used to correct vertex order after geopoly_xform().
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SHA3-256:bfc897c9c02eebf5321dc7c222fabb563223be23d454eec627a487af91dbce55
User & Date: drh 2018-11-24 20:58:44
Context
2018-11-26
12:01
Merge typo fix from the 3.25 branch. check-in: 121aeee579 user: drh tags: trunk
2018-11-24
20:58
In the GeoPoly documentation, mention that geopoly_ccw() can be used to correct vertex order after geopoly_xform(). check-in: bfc897c9c0 user: drh tags: trunk
20:24
Minor enhancements and updates to various documents. check-in: 9e12c649c9 user: drh tags: trunk
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Changes to pages/geopoly.in.

   275    275   <p>
   276    276   To rotate a polygon by R radians around the point 0, 0:
   277    277   
   278    278   <codeblock>
   279    279   geopoly_xform($polygon, cos($R), sin($R), -sin($R), cos($R), 0, 0)
   280    280   </codeblock>
   281    281   
          282  +<p>
          283  +Note that a transformation that flips the polygon might cause the
          284  +order of vertexes to be reversed.  In other words, the transformation
          285  +might cause the vertexes to circulate in clockwise order instead of
          286  +counter-clockwise.  This can be corrected by sending the result
          287  +through the [geopoly_ccw()] function after transformation.
          288  +
   282    289   
   283    290   <tcl>hd_fragment regpoly geopoly_regular</tcl>
   284    291   <h2>The geopoly_regular(X,Y,R,N) Function</h2>
   285    292   
   286    293   <p>
   287    294   The geopoly_regular(X,Y,R,N) function returns a convex, simple, regular,
   288    295   equilateral, equiangular polygon with N sides, centered at X,Y, and with