I think this is likely a bug, but I'm first posting to the mailing list to see if there might be some way I can control this with via my map file.
This is best seen by a picture. [Hopefully attaching files worked; I haven't attached files to msgs here before.] What's going on is that it looks like the end of a line is determined by the point at which the center of the line reaches the edge of the map, not the points at which the edges of the line reach the edge of the map. This is significant if you have a line wider than 1 pixel, and it becomes more significant as the angle between the line and the edge becomes shallower. In the attached images, the road network is rectangular, but offset a bit from a pure N/S/E/W grid. Look at what happens to the roads at the edges. They look like they end prematurely. This happens when rendered in both AGG and GD. *.map files are pasted inline below. --- begin streetbug.agg.map --- MAP NAME streetbug-agg IMAGETYPE AGG_Q OUTPUTFORMAT NAME 'AGG_Q' DRIVER AGG/PNG IMAGEMODE RGB FORMATOPTION "QUANTIZE_FORCE=ON" FORMATOPTION "QUANTIZE_DITHER=OFF" FORMATOPTION "QUANTIZE_COLORS=256" END EXTENT -122.2914 37.8396 -122.2892 37.841 ANGLE 0 SIZE 640 480 IMAGECOLOR 204 204 204 LAYER NAME LocalRoads STATUS DEFAULT # DEFAULT means on. change to OFF to enable via URL parameter (&layer=foo) TYPE LINE CONNECTIONTYPE postgis CONNECTION "dbname=navteq user=navteq host=agua" DATA "the_geom FROM streets" CLASS NAME "Local Roads" STYLE COLOR 248 248 248 WIDTH 11 END END END END --- end streetbug.agg.map --- --- begin streetbug.gd.map --- MAP NAME streetbug-gd IMAGETYPE PNG EXTENT -122.2914 37.8396 -122.2892 37.841 ANGLE 0 SIZE 640 480 IMAGECOLOR 204 204 204 LAYER NAME LocalRoads STATUS DEFAULT # DEFAULT means on. change to OFF to enable via URL parameter (&layer=foo) TYPE LINE CONNECTIONTYPE postgis CONNECTION "dbname=navteq user=navteq host=agua" DATA "the_geom FROM streets" CLASS NAME "Local Roads" STYLE COLOR 248 248 248 WIDTH 11 END END END END --- end streetbug.gd.map --- -- View this message in context: http://www.nabble.com/wide-lines-not-complete-at-the-edges-tp14609249p14609249.html Sent from the Mapserver - User mailing list archive at Nabble.com.