Forgot to cc the list… Thanks Steve,
The most visible problem is that the centroid values I'm getting are the same for all shapes in the output. It's a United States map, and for all states in the result set, the "centroid" comes out to the same point, somewhere around Wyoming. The rest of the output is expected: a set of vertices for each shape that correctly renders the imagemap. But, since the centroid is supposed to be a simple center of the bounding box, it probably won't do what I need anyway. Thanks, Kent On Apr 12, 2013, at 8:40 AM, Lime, Steve D (MNIT) wrote: > The centroid in the shpxy code is very basic and not a true centroid, it's > just the mid-point of the bounding box of shape in question. It really > wouldn't need to be this simple I think. The computation of that value is > done on the raw shape and converted to image coordinates. I'm guessing it's > the way the "centroid" is computed that is causing the problem? > > Steve > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Kent Richards > Sent: Sunday, March 31, 2013 1:13 AM > To: [email protected] > Subject: [mapserver-users] Need help with shpxy centriod in template file > > When using the imagemap output in mapscript, I'm trying to get the center of > the shapes using [shpxy precision=0 proj=image centroid=true]. > > Perhaps the first most obvious question is: am I misunderstanding what > "centroid" means in this case? I thought it meant the geometric center of > the shape (of each shape, in this case). > > I have an imagemap TEMPLATE file with this declaration: > >> <!-- MapServer Template --> >> <area class="[shpxy precision=0 proj=image centroid=true xh="x" xf="-" >> yh="y" sh="center-"]" shape="poly" coords="[shpxy precision=0 proj=image]" >> href="http://my.url/mypage.cfm?ID=[state]"; title="[state]" alt="[state]"> > > > The [shpxy centroid-true...] part returns "center-x367-y128" *for each shape* > (the raw coords are 367, 128). > > 367, 128 is not in the center of the image, nor in the center of most of the > shapes. > > The other shpxy declaration in the template -- for the coords attribute -- > seems to behave as expected. > > Any ideas what I'm doing wrong, or is this a bug? > > I know I can rig a convoluted means to return just the polygon points and > calculate a center of sorts myself, but I'd like to just use the mapserver > feature if it works. > > Thanks, > > Kent > _______________________________________________ > mapserver-users mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/mapserver-users > > _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
