[Mapserver-users] normal behaviour of line drawing?

[Steve Lime]

Drawing is done in the order the features are fed to MapServer. Class only affects how they look. Class order does affect the order in which expressions are evaluated (first match is used) so you can exploit that fact. The real issue is sorting of features so you can control the order. MapServer does not allow you to sort shapefiles at runtime (you could file a feature request for this if you like). This is mainly for performance reasons. There is a sortshp utility packaged with MapServer that allows you to re-order a shapefile. You might sort on road type so streets show up beneath ramps and ramps below highways. This also helps set label priority too...

Steve

Stephen Lime
Data & Applications Manager

Minnesota DNR
500 Lafayette Road
St. Paul, MN 55155
651-297-2937

>>> Michael Schulz <mschulz at webgis.de> 7/8/2004 10:24:26 AM >>>
Hi,

i have attached an image which shows some line crossings drawn with mapserver-4.2beta (i know it's a 
bit old ...). But i found this problems with other (only older) versions too.

The layer with the 3 classes (Autobahn, Bundesstrasse, Landstrasse) has overlapping lines. But as 
you can see in the picture not one class gets drawn over the other, but line symbols are sometimes 
over, sometimes under another class. I thought the order of the classes in a layer effects also the 
drawing, but i might be mistaken.

Has the line drawing been updated in the latest versions? If so, i will try it with a newer version. 
Or should i file a bug?

Cheers, Michael


-- 
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Michael Schulz                                in medias res
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