Re: [mapserver-users] Displaying overlapping linestrings
Yes, the idea works, but the differences in hue are too small to be useful in practice. And furthermore, they also show up for border lines between adjoining polygons. I just want to highlight polygons that completely overlap. I'm afraid I have to go the PostGIS/GEOS way. Even o, would an XOR brush not be a nice addition to the STYLE object? You could create all kinds of moiré fill patterns. http://www.google.nl/search?q=moire&hl=en&client=firefox-a&hs=lGh&tbo=u&rls=org.mozilla:en-GB:official&tbm=isch&source=univ&sa=X&ei=C1UCUez4C9KX0QXV9IDoDw&ved=0CFMQsAQ&biw=1600&bih=809 Jan On 1/24/2013 6:36 PM, Lime, Steve D (DNR) wrote: You could try drawing the features with the same base color but with opacity set. The more times the same area is rendered you'd get a different hue. Steve *From:*mapserver-users-boun...@lists.osgeo.org [mailto:mapserver-users-boun...@lists.osgeo.org] *On Behalf Of *Jan Hartmann *Sent:* Thursday, January 24, 2013 11:00 AM *To:* Stephen Woodbridge *Cc:* mapserver-users@lists.osgeo.org *Subject:* Re: [mapserver-users] Displaying overlapping linestrings On 01/24/2013 05:35 PM, Stephen Woodbridge wrote: On 1/24/2013 11:13 AM, Jan Hartmann wrote: Does anyone know a trick to do this: I'm making geographical indexes for the map series in our map library. Each map sheets is displayed as a polygonal linestring, based on its corner coordinates. Lots of sheets have exactly the same boundaries, so it's not clear where a polygon indicates just one map sheet of several. It's easy, of course, to write a PostGIS query to return a different color code when map boundaries exactly coincide, but I was wondering whether something like that could be done by mapserver on its own, like XOR-ing a line with what is already there. Any ideas? Hi Jan, For polygons you could use a small negative buffer to shrink the polygon slightly. You can do this in postgis, and you might be able to do it with mapserver if geos is compiled in. See: http://mapserver.org/development/rfc/ms-rfc-48.html No, that is not what I meant. I'm looking for a trick for mapserver to color a linestring differently when drawing over a linestring that it has already drawn in a previous layer. In computer graphics you can do this by using an XOR brush. Essentially, the screen frame buffer functions as a sort of memory. I don not want to use PostGIS or GOS, too complex. I doubt if this can be done by MapServer, but you never know. Jan ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: [mapserver-users] Displaying overlapping linestrings
You could try drawing the features with the same base color but with opacity set. The more times the same area is rendered you'd get a different hue. Steve From: mapserver-users-boun...@lists.osgeo.org [mailto:mapserver-users-boun...@lists.osgeo.org] On Behalf Of Jan Hartmann Sent: Thursday, January 24, 2013 11:00 AM To: Stephen Woodbridge Cc: mapserver-users@lists.osgeo.org Subject: Re: [mapserver-users] Displaying overlapping linestrings On 01/24/2013 05:35 PM, Stephen Woodbridge wrote: On 1/24/2013 11:13 AM, Jan Hartmann wrote: Does anyone know a trick to do this: I'm making geographical indexes for the map series in our map library. Each map sheets is displayed as a polygonal linestring, based on its corner coordinates. Lots of sheets have exactly the same boundaries, so it's not clear where a polygon indicates just one map sheet of several. It's easy, of course, to write a PostGIS query to return a different color code when map boundaries exactly coincide, but I was wondering whether something like that could be done by mapserver on its own, like XOR-ing a line with what is already there. Any ideas? Hi Jan, For polygons you could use a small negative buffer to shrink the polygon slightly. You can do this in postgis, and you might be able to do it with mapserver if geos is compiled in. See: http://mapserver.org/development/rfc/ms-rfc-48.html No, that is not what I meant. I'm looking for a trick for mapserver to color a linestring differently when drawing over a linestring that it has already drawn in a previous layer. In computer graphics you can do this by using an XOR brush. Essentially, the screen frame buffer functions as a sort of memory. I don not want to use PostGIS or GOS, too complex. I doubt if this can be done by MapServer, but you never know. Jan ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: [mapserver-users] Displaying overlapping linestrings
On 01/24/2013 05:35 PM, Stephen Woodbridge wrote: On 1/24/2013 11:13 AM, Jan Hartmann wrote: Does anyone know a trick to do this: I'm making geographical indexes for the map series in our map library. Each map sheets is displayed as a polygonal linestring, based on its corner coordinates. Lots of sheets have exactly the same boundaries, so it's not clear where a polygon indicates just one map sheet of several. It's easy, of course, to write a PostGIS query to return a different color code when map boundaries exactly coincide, but I was wondering whether something like that could be done by mapserver on its own, like XOR-ing a line with what is already there. Any ideas? Hi Jan, For polygons you could use a small negative buffer to shrink the polygon slightly. You can do this in postgis, and you might be able to do it with mapserver if geos is compiled in. See: http://mapserver.org/development/rfc/ms-rfc-48.html No, that is not what I meant. I'm looking for a trick for mapserver to color a linestring differently when drawing over a linestring that it has already drawn in a previous layer. In computer graphics you can do this by using an XOR brush. Essentially, the screen frame buffer functions as a sort of memory. I don not want to use PostGIS or GOS, too complex. I doubt if this can be done by MapServer, but you never know. Jan ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: [mapserver-users] Displaying overlapping linestrings
On 1/24/2013 11:13 AM, Jan Hartmann wrote: Does anyone know a trick to do this: I'm making geographical indexes for the map series in our map library. Each map sheets is displayed as a polygonal linestring, based on its corner coordinates. Lots of sheets have exactly the same boundaries, so it's not clear where a polygon indicates just one map sheet of several. It's easy, of course, to write a PostGIS query to return a different color code when map boundaries exactly coincide, but I was wondering whether something like that could be done by mapserver on its own, like XOR-ing a line with what is already there. Any ideas? Hi Jan, For polygons you could use a small negative buffer to shrink the polygon slightly. You can do this in postgis, and you might be able to do it with mapserver if geos is compiled in. See: http://mapserver.org/development/rfc/ms-rfc-48.html Steve W ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
[mapserver-users] Displaying overlapping linestrings
Does anyone know a trick to do this: I'm making geographical indexes for the map series in our map library. Each map sheets is displayed as a polygonal linestring, based on its corner coordinates. Lots of sheets have exactly the same boundaries, so it's not clear where a polygon indicates just one map sheet of several. It's easy, of course, to write a PostGIS query to return a different color code when map boundaries exactly coincide, but I was wondering whether something like that could be done by mapserver on its own, like XOR-ing a line with what is already there. Any ideas? Jan ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
