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    <p>Hello,</p>
    <p>I have a problem that has already been discussed in stackexchange
(<a class="moz-txt-link-freetext" href="https://gis.stackexchange.com/questions/440902/mapserver-wms-not-all-features-show-depending-on-how-i-zoom-and-pan">https://gis.stackexchange.com/questions/440902/mapserver-wms-not-all-features-show-depending-on-how-i-zoom-and-pan</a>),
      but without solution so far.</p>
    <p>I'm repeating the full text here, but if there's any problem with
      the images it might be better to go to stackexchange to read it.</p>
    <p>Here is how QGIS shows an irrigation network, received by
      MapServer via WMS and superimposed on OpenStreetMap:</p>
    <p><img src="https://i.stack.imgur.com/bCOib.png" alt="enter image
        description here"></p>
    <p>Here is the same thing, but slightly panned to the right:</p>
    <p><img src="https://i.stack.imgur.com/Ca7Tc.png" alt="enter image
        description here"></p>
    <p>Several items are obviously missing. In fact there are items
      missing in the top picture as well. Different items become visible
      as I zoom and pan differently.</p>
    <p>Since this pretty much tells the whole story, I'm not going into
      more details. MapServer version is 7.6.2 (prepackaged for Debian).
      The base URL is
<a class="moz-txt-link-freetext" href="https://poros.irmasys.com/cgi-bin/mapserv?map=/opt/aira-poros/aira-poros/mapserver/extralayers.map">https://poros.irmasys.com/cgi-bin/mapserv?map=/opt/aira-poros/aira-poros/mapserver/extralayers.map</a>.
      Finally, below I paste the interesting parts of the mapfile.</p>
    <p>Thanks!</p>
    <p>Antonis</p>
    <p><br>
    </p>
    <p><br>
    </p>
    <br>
    <pre><code>MAP
    NAME "aira-poros"
    STATUS ON
    SIZE 9040 7731
    EXTENT 103986.57 3850796.18 1007945.14 4623933.00
    UNITS meters
    PROJECTION
        "init=epsg:2100"
    END
    CONFIG MS_ERRORFILE "/var/log/mapserver/extralayers.log"

    # [Omitting some OUTPUTFORMAT sections]

    WEB
        IMAGEPATH "/var/cache/mapserver/"
        IMAGEURL "/mapserver_tmp/"
        METADATA
            "wms_title" "Aira Poros"
            "wms_onlineresource" <a class="moz-txt-link-rfc2396E" href="https://poros.irmasys.com/cgi-bin/mapserv?map=/opt/aira-poros/aira-poros/mapserver/extralayers.map&">"https://poros.irmasys.com/cgi-bin/mapserv?map=/opt/aira-poros/aira-poros/mapserver/extralayers.map&"</a>
            "wms_srs" "EPSG:4326 EPSG:2100 EPSG:3857"
            "wms_enable_request" "*"
            "wms_feature_info_mime_type" "text/html"

            "wfs_title" "Aira Poros"
            "wfs_onlineresource" <a class="moz-txt-link-rfc2396E" href="https://poros.irmasys.com/cgi-bin/mapserv?map=/opt/aira-poros/aira-poros/mapserver/extralayers.map&">"https://poros.irmasys.com/cgi-bin/mapserv?map=/opt/aira-poros/aira-poros/mapserver/extralayers.map&"</a>
            "wfs_srs" "EPSG:2100 EPSG:4326 EPSG:3857"
            "wfs_enable_request" "*"
        END
    END

    LAYER
        NAME "irrigation-network" 
        TYPE LINE
        CONNECTIONTYPE OGR
        CONNECTION "irrigation-network.gml"
        METADATA
            "wms_title" "Irrigation network"
            "wfs_title" "Irrigation network"
            "gml_include_items" "all"
            "gml_featureid" "id"
        END
        STATUS ON
        PROJECTION
            "init=epsg:2100"
        END
        CLASSITEM 'category'
        CLASS
            EXPRESSION '1'
            STYLE
                COLOR 0 0 255
                OPACITY 50
                WIDTH 6
            END
            LABEL
                COLOR 0 0 255
                ANGLE FOLLOW
                OFFSET 5 99
                MAXSCALEDENOM 10000
                TEXT "[irri_code]"
            END
            LABEL
                COLOR 0 0 255
                ANGLE FOLLOW
                OFFSET -8 99
                MAXSCALEDENOM 10000
                EXPRESSION (NOT('[Diameter]' = ''))
                TEXT "D=[Diameter] mm"
            END
        END

        # [Omitting three more classes]
    END

    # [Omitting four more layers]
END</code></pre>
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