Here's an example that draws a 1km diameter two different ways: http://maps.dnr.state.mn.us/mapserver_demos/circles.map
It shows two ways to do this. One using a circle layer and the other using a circle symbol but with different size units (e.g. non-pixel). Apparently a circle layer takes features consisting of two points where the points are on the circle and directly opposite one another. Their mid-point defines the center point. Why I did it this way is a bit of a mystery but it is what it is... The buffer method is also perfectly valid. Steve -----Original Message----- From: Helen Eskina [mailto:[email protected]] Sent: Friday, December 18, 2009 9:23 AM To: Lime, Steve D (DNR) Subject: RE: [mapserver-users] How to draw a circle using MapScript? Hi Steve, Thank you for the reply! Looking forward to your example! Helen -----Original Message----- From: Lime, Steve D (DNR) [mailto:[email protected]] Sent: Thursday, December 17, 2009 6:29 PM To: Lime, Steve D (DNR); Dan Little; Helen Eskina; [email protected] Subject: RE: [mapserver-users] How to draw a circle using MapScript? After mulling this over I think I'm wrong. Conceptually it's correct but the points represent the center and a point on the circle I think. I'll post a stand-alone example later tonite... Steve ________________________________________ From: [email protected] [[email protected]] On Behalf Of Lime, Steve D (DNR) [[email protected]] Sent: Thursday, December 17, 2009 4:30 PM To: Dan Little; Helen Eskina; [email protected] Subject: RE: [mapserver-users] How to draw a circle using MapScript? In another approach, I believe MapServer wants you to define a bounding box for the circle by creating a line shape with the first point at the UL coordinate of that box and the second coordinate at the LR coordinate of the box. So you'd offset your center point .5 KM to create those points. You can add the resulting shape to the appropriate layer to draw it. I'll check to make sure, but I think that will work. Steve From: [email protected] [mailto:[email protected]] On Behalf Of Dan Little Sent: Thursday, December 17, 2009 3:54 PM To: Helen Eskina; [email protected] Subject: Re: [mapserver-users] How to draw a circle using MapScript? Totally off the cuff.... $shape = ms_shapeObjFromWKT('POINT('+$x+' '+$y+')'); $shape = $shape->buffer($radius); From: Helen Eskina <[email protected]> To: [email protected] Sent: Thu, December 17, 2009 3:50:20 PM Subject: [mapserver-users] How to draw a circle using MapScript? Hello List, I want to be able to draw a circle dynamically using PHP MapScript. The circle is defined by the coordinates of the centre and the radius in kilometers. I realize that the circle is a polygon and I should probably calculate all points. What is the best way to do it? I would really appreciate any help! Thank you, Helen No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.427 / Virus Database: 270.14.103/2558 - Release Date: 12/17/09 08:30:00 _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
