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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hi Peter: The functions you’re looking for are msOffsetPolyline() and msOffsetCurve() in maputil.c. We do use GEOS if it’s available though and fall back to
our own code only if necessary.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Steve<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> mapserver-users-bounces@lists.osgeo.org [mailto:mapserver-users-bounces@lists.osgeo.org]
<b>On Behalf Of </b>Peter Maes<br>
<b>Sent:</b> Monday, July 07, 2014 4:32 AM<br>
<b>To:</b> mapserver-users@lists.osgeo.org<br>
<b>Subject:</b> [mapserver-users] algorithm for line offset (-99 value)<o:p></o:p></span></p>
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<p class="MsoNormal">Hi,<o:p></o:p></p>
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<p class="MsoNormal">In the past we only rendered image tiles for roads, where we need the 2 lanes to be drawn separately. For this we've been using the -99 value offset parameter.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">However, now we need to use mapserver wfs on the vector side and do this line offset on the client.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Can anyone point me to the right direction on how this is implemented? Unfortunately I can't read c very well so digging in the mapserver source also seems difficult.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Perhaps if I know where to look for?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Given a WKT linestring (either WGS84 or EPSG 900913) how could I offset it a few pixels in direction of the line?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks for any help or pointers.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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