<HTML dir=ltr><HEAD><TITLE>Re: [OpenLayers-Users] Circles</TITLE>
<META http-equiv=Content-Type content="text/html; charset=unicode">
<META content="MSHTML 6.00.6001.18148" name=GENERATOR></HEAD>
<BODY>
<DIV id=idOWAReplyText5020 dir=ltr>
<DIV dir=ltr><FONT face=Arial color=#000000 size=2>You are absolutly correct and my frustrations are more centered on specifications than on OpenLayers.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2>You are spot on that having a circle geometry whould mean nothing to the community if it couldn't be represented in the standard specifications like GML, WKT, KML, etc.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>It just saddens me that the lack of circle support in the specs has led to work-arounds and abuses that should never have needed to exist.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>WKT's lack of circle support lead Oracle to create CURVEPOLYGON which is completely unsupported by anything, even though Oracle outputs it as valid WKT.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2>Although you are correct that a RegularPolygon with many sides can look like a circle, calculations based off that shape can be severly flawed when treated as one.</FONT></DIV></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT>
<DIV dir=ltr><FONT face=Arial size=2>if i were to make an app that fetched data within a drawn circle, my results could prove to be highly inacurate by the lack of true curveature.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr>
<HR tabIndex=-1>
</DIV>
<DIV dir=ltr><FONT face=Tahoma size=2><B>From:</B> Christopher Schmidt [mailto:crschmidt@metacarta.com]<BR><B>Sent:</B> Mon 12/8/2008 2:07 PM<BR><B>To:</B> Heidt, Christopher M.<BR><B>Cc:</B> users@openlayers.org<BR><B>Subject:</B> Re: [OpenLayers-Users] Circles<BR></FONT><BR></DIV></DIV>
<DIV>
<P><FONT size=2>On Mon, Dec 08, 2008 at 01:45:55PM -0500, Heidt, Christopher M. wrote:<BR>> this is definitly a clever aproach, but it is still a work-around for what i consider to be a basic shape.<BR>> I just wonder why i cant have something along the lines of: new Openlayers.Geometry.Circle(lon,lat,radius);<BR><BR>Adding a new Geometry type is about more than just creating the<BR>geometry. What should happen when the GML writer encounters a circle?<BR>How does a renderer which doesn't have circle types as built ins handle<BR>it? etc. etc.<BR><BR>Adding a new Geometry type probably ends up affecting more than a dozen<BR>different classes in OpenLayers in ways that are ill defined. Sure, we<BR>culd make it easier to draw a circle -- but the REgularPolygon ends up<BR>having the same result, with not a very different API than you're<BR>proposing, and has the benefit that it works with all the existing<BR>functionality built around the Simple Features specifications that<BR>OpenLayers vector support is based on.<BR><BR>Is it unfortunate that circles are not a 'default' geometry type in more<BR>specifications? Maybe. But I don't understand why the RegularPolygon --<BR>which creates a visual circle, but has the benefit of being usable in<BR>software other than OpenLayers -- is such a problem.<BR><BR>Help me understand?<BR><BR>Regards,<BR>--<BR>Christopher Schmidt<BR>MetaCarta<BR></FONT></P></DIV></BODY></HTML>