[mapserver-users] Angle Follow will accept only simple linestring don't MultiLinestring ?

Andrea Peri aperi2007 at gmail.com
Tue Aug 13 14:31:32 PDT 2013


Hi,
Perhaps I found the explanation.

The "angle follow" with OGR is using the
BufferBuilder::bufferLineSingleSided
That function seem don't work with a MultiLinestring . It necessary need a
simple linestring.

The question is that sometime the simple linestirng when is clipped from
the visible bbox of the map to render, is transformed in a MultiLinestring.
As showed in attached image.

So a linestring geometry clipped by the visible bbox will become a
multilinestring geometry and the bufferLineSingleSided will give error to
put a "follow angle".

Andrea.

2013/8/13 Andrea Peri <aperi2007 at gmail.com>

> ok, thx.
> I change to multiple scale.
>
> However I do a rapid check removing a label component, but the problem is
> still here.
>
> Now I rewrite a more exact mapfile using two classes.
>
> Andrea.
>
>
>
>
> 2013/8/13 thomas bonfort <thomas.bonfort at gmail.com>
>
>> yes, that's incompatible. use multiple scale-dependant classes for now
>>
>> On 13 August 2013 18:26, Andrea Peri <aperi2007 at gmail.com> wrote:
>> > The two label are at different max/min scaledenominator.
>> > The goal is to have little label size at low scales and bigger font
>> size at
>> > bigger scales.
>> >
>> > However only one lable is active at one scale level.
>> >
>> > Is this incompatible with "follow" ?
>> >
>> >
>> >
>> > 2013/8/13 thomas bonfort <thomas.bonfort at gmail.com>
>> >>
>> >> why the double label? they seem to be the same, but in any case
>> >> multiple labels are not supported for FOLLOW.
>> >>
>> >> On 13 August 2013 18:08, Andrea Peri <aperi2007 at gmail.com> wrote:
>> >> > I'm using spatialite 4.1.1,
>> >> > so use ogr to access the db.
>> >> >
>> >> >   LAYER
>> >> >     NAME "rt_topogr.50k.etichette.topon_idro_50k"
>> >> >     STATUS OFF
>> >> >     EXTENT 1554750.74 4678325.52 1771722.76 4924791.90
>> >> >     TYPE LINE
>> >> >     CONNECTIONTYPE OGR
>> >> >     CONNECTION "/path-to-spatialite/zz_topografica.sqlite"
>> >> >     DATA "select PK_UID_2, TOPO_OK, GEOMETRY from topon_idro_50k"
>> >> >     PROJECTION
>> >> >       "+init=epsg:3003 +towgs84=0,0,0,0,0,0,0"
>> >> >     END
>> >> >     METADATA
>> >> >       "wms_title" "topon_idro_50k"
>> >> >       "wms_extent" "1554750.74 4678325.52 1771722.76 4924791.90"
>> >> >     END
>> >> >     LABELCACHE ON
>> >> >     MAXSCALEDENOM 60100
>> >> >     MINSCALEDENOM 1
>> >> >     CLASS
>> >> >       NAME ''
>> >> >       MAXSCALEDENOM 60100
>> >> >       MINSCALEDENOM 1
>> >> >       LABEL
>> >> >         TEXT '[TOPO_OK]'
>> >> >         COLOR 0 85 255
>> >> >         OUTLINECOLOR 212 255 255
>> >> >         OUTLINEWIDTH 1
>> >> >         MAXSCALEDENOM 60100
>> >> >         MINSCALEDENOM 40100
>> >> >         FONT "LiberationSans-Regular"
>> >> >         TYPE truetype
>> >> >         SIZE 7
>> >> >         ANGLE FOLLOW
>> >> >         OFFSET 15 99
>> >> >         POSITION auto
>> >> >         PRIORITY 10
>> >> >         MAXOVERLAPANGLE 180.0
>> >> >         BUFFER 1
>> >> >         FORCE OFF
>> >> >         PARTIALS FALSE
>> >> >         MINDISTANCE 200
>> >> >       END
>> >> >       LABEL
>> >> >         TEXT '[TOPO_OK]'
>> >> >         COLOR 0 85 255
>> >> >         OUTLINECOLOR 212 255 255
>> >> >         OUTLINEWIDTH 1
>> >> >         MAXSCALEDENOM 40100
>> >> >         MINSCALEDENOM 1
>> >> >         FONT "LiberationSans-Regular"
>> >> >         TYPE truetype
>> >> >         SIZE 9
>> >> >         ANGLE FOLLOW
>> >> >         OFFSET 15 99
>> >> >         POSITION auto
>> >> >         PRIORITY 10
>> >> >         MAXOVERLAPANGLE 180.0
>> >> >         BUFFER 1
>> >> >         FORCE OFF
>> >> >         PARTIALS FALSE
>> >> >         MINDISTANCE 200
>> >> >       END
>> >> >     END
>> >> >   END
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > 2013/8/13 thomas bonfort <thomas.bonfort at gmail.com>
>> >> >>
>> >> >> there's something strange in your error message... the
>> >> >> singleSidedBuffer stuff is in GEOS, and should have nothing to do in
>> >> >> msOGRFileNextShape. post your whole mapfile layer.
>> >> >>
>> >> >> On 13 August 2013 17:42, Andrea Peri <aperi2007 at gmail.com> wrote:
>> >> >> > Hi,
>> >> >> >
>> >> >> > I tested trasforming the multilinestring dataset in a linestring
>> >> >> > dataset
>> >> >> > but
>> >> >> > the error is still here.
>> >> >> >
>> >> >> > msDrawMap(): Image handling error. Failed to draw layer named
>> >> >> > 'rt_topogr.50k.etichette.topon_idro_50k'.
>> >> >> >
>> >> >> > msOGRFileNextShape(): OGR error. IllegalArgumentException:
>> >> >> > BufferBuilder::bufferLineSingleSided only accept linestrings
>> >> >> >
>> >> >> > So it is not really due to a multilinestring vs linestring
>> question.
>> >> >> >
>> >> >> > The quest carry on.
>> >> >> >
>> >> >> >
>> >> >> >
>> >> >> > 2013/8/13 Andrea Peri <aperi2007 at gmail.com>
>> >> >> >>
>> >> >> >> Hi,
>> >> >> >>
>> >> >> >> Try.ing to set a label on a MULTILINESTRING dataset.
>> >> >> >>
>> >> >> >> I set a label with Follow capability.
>> >> >> >>
>> >> >> >>         ANGLE FOLLOW
>> >> >> >>
>> >> >> >> But I'm having this error:
>> >> >> >>
>> >> >> >>  msOGRFileNextShape(): OGR error. IllegalArgumentException:
>> >> >> >> BufferBuilder::bufferLineSingleSided only accept linestrings
>> >> >> >>
>> >> >> >> Is the Follow compatible with a MultiLinestring dataset or need
>> only
>> >> >> >> simple linestrings ?
>> >> >> >>
>> >> >> >> Thx,
>> >> >> >>
>> >> >> >> --
>> >> >> >> -----------------
>> >> >> >> Andrea Peri
>> >> >> >> . . . . . . . . .
>> >> >> >> qwerty àèìòù
>> >> >> >> -----------------
>> >> >> >
>> >> >> >
>> >> >> >
>> >> >> >
>> >> >> > --
>> >> >> > -----------------
>> >> >> > Andrea Peri
>> >> >> > . . . . . . . . .
>> >> >> > qwerty àèìòù
>> >> >> > -----------------
>> >> >> >
>> >> >> > _______________________________________________
>> >> >> > mapserver-users mailing list
>> >> >> > mapserver-users at lists.osgeo.org
>> >> >> > http://lists.osgeo.org/mailman/listinfo/mapserver-users
>> >> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > --
>> >> > -----------------
>> >> > Andrea Peri
>> >> > . . . . . . . . .
>> >> > qwerty àèìòù
>> >> > -----------------
>> >
>> >
>> >
>> >
>> > --
>> > -----------------
>> > Andrea Peri
>> > . . . . . . . . .
>> > qwerty àèìòù
>> > -----------------
>>
>
>
>
> --
> -----------------
> Andrea Peri
> . . . . . . . . .
> qwerty àèìòù
> -----------------
>



-- 
-----------------
Andrea Peri
. . . . . . . . .
qwerty àèìòù
-----------------
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/mapserver-users/attachments/20130813/326bed80/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: img1.gif
Type: image/gif
Size: 1983 bytes
Desc: not available
URL: <http://lists.osgeo.org/pipermail/mapserver-users/attachments/20130813/326bed80/attachment.gif>


More information about the mapserver-users mailing list