[mapserver-users] Railroad and dual carriage way styles

[Hockaday, John]

Steve,

Thanks for this detailed information.  Is seems that all possibilities are
allowed for by the new method.  The problem is trying to find examples of
how to use them.  Is it possible, once you have developed some examples on
the weekend, that we can have a simple mapserver in the tutorials showing
the symbol set, the map file and lots of examples using those symbols
showing common cartographic examples?  EG. Dual carriageways, airports,
railways, capital cities, local towns, rivers, etc. etc.  Could it also show
a GROUP example?  EG. Roads as single lines on a national basis but as one
zooms it the dual carriageways show up.

I know that this is asking a fair bit but the documentation doesn't quite
explain things using examples.  A picture, using examples, can say a
thousand words and I know that user documentation is the last thing on a
developers mind.  ;--)

Thanks for all your help.

John

> -----Original Message-----
> From:	Stephen Lime [SMTP:steve.lime at dnr.state.mn.us]
> Sent:	Friday, December 14, 2001 3:48 PM
> To:	JohnHockaday at auslig.gov.au
> Cc:	mapserver-users at lists.gis.umn.edu
> Subject:	RE: [mapserver-users] Railroad and dual carriage way styles
> 
> The problem with the old format was that the offset piece was just an
> approximation and fell apart in certain instances (like hairpin corners).
> Some simple rules were used to calculate the offset and this resulted in
> things like railroad tracks in which tracks were not perpendicular to the
> rail. In experimentation before I made the switch I found that I could
> create most every symbol with the new system that the old one supported.
> The only major deficiency was that truely hollow lines couldn't be
> supported. You can make parallel lines with space between them but you
> can't see stuff underlying the space. The new system allows for a wide
> variety of new symbols with more flexible color schemes that really does
> boost performance. For example, it used to be that to create a red
> centerline with a black outline took 2 layer defs (and 2 passes over the
> data). Now that is done in one pass. In addition you get things like fat
> polygon outlines. I'll try and post some samples over the weekend.
> 
> If we find a particular deficiency I would propose adding a couple of new
> line symbol types specifically to address them. I don't want to go back to
> offsets though.
> 
> Steve
> 
> Stephen Lime
> Data & Applications Manager
> 
> Minnesota DNR
> 500 Lafayette Road
> St. Paul, MN 55155
> 651-297-2937
> >>> "Hockaday, John" <JohnHockaday at auslig.gov.au> 12/13/01 21:34 PM >>>
> Steve,
> 
> This was a big help.  I managed to get some lines that look similar to the
> original formats.  
> 
> I feel that the Mapserver 3.4 offset capability of the STYLE tag was much
> easier to use, understand and looked better.  
> 
> Developers,
> 
> Are there any intentions to reintroduce the offset capability to the STYLE
> tag?    Please, please, please say yes!!!  It's much easier to use!!!
> ;--)
> 
> Thanks again to this list for a quick and accurate response.
> 
> John
> 
> > -----Original Message-----
> > From:	Stephen Woodbridge [SMTP:woodbri at swoodbridge.com]
> > Sent:	Friday, December 14, 2001 12:16 AM
> > To:	Hockaday, John
> > Cc:	'mapserver-users at lists.gis.umn.edu'
> > Subject:	Re: [mapserver-users] Railroad and dual carriage way styles
> > 
> > 
> > John,
> > 
> > I have had no answer to my query on railway symbols, but did come up
> > with a idea for a good looking alternative based on a dual carriageway
> > in 3.5.
> > 
> > dual carriageway:
> > 
> > SYMBOL 'circle'
> > COLOR 0 0 0
> > SIZE 5
> > OVERLAYSYMBOL 'circle'
> > OVERLAYCOLOR 255 0 0
> > OVERLAYSIZE 3
> > 
> > railway:
> > 
> > SYMBOL 'circle'
> > COLOR 0 0 0
> > SIZE 5
> > OVERLAYSYMBOL 'dcircle'
> > OVERLAYCOLOR 255 255 255
> > OVERLAYSIZE 3
> > 
> > where 'dcircle' is defined as:
> > 
> > SYMBOL
> >   NAME 'dcircle'
> >   TYPE ELLIPSE
> >   FILLED TRUE
> >   POINTS 1 1 END
> >   STYLE 5 5 END
> > END
> > 
> > The other idea I had was to do an overlay to generate --0--0--0--0--
> > where the circles are filled, you could use "STYLE 1 5 END" above
> > instead.
> > 
> > I hope this helps,
> >   -Steve
> > 
> > "Hockaday, John" wrote:
> > > 
> > > Hi,
> > > 
> > > I noticed a while ago in the archives that some one wanted to know how
> > to
> > > make a railroad line in Mapserver 3.5 map files.  I couldn't find any
> > > answers to that question so I am asking this one.
> > > 
> > > In Mapserver 3.4 one could generate a dual carriageway by way of
> > offsets.
> > > eg
> > > 
> > > STYLE
> > >   -1 0 0
> > >     1 0 0
> > > END
> > > 
> > > but in Mapserver 3.5 it seems that the STYLE doesn't have offsets.
> > > 
> > > How do I generate a railway   "---|---" and how do I generate a dual
> > > carriageway "==="?
> > > 
> > > Thanks in advance.
> > > 
> > > John