Home » railML newsgroups » railml.infrastructure » [railML2] @dir
[railML2] @dir [message #2194] Mon, 27 May 2019 11:57 Go to previous message
christian.rahmig is currently offline  christian.rahmig
Messages: 260
Registered: January 2016
Senior Member
Dear active railML community,

the new Common scheme coordinator Thomas (together with Janne from JBD)
initiated a discussion about the meaning and usage of the attribute
@dir. While the starting point of the discussion was at the element
<levelCrossing> (cp. [1]) the attribute is available for almost all
instances of <trackElements> and <ocsElements> and therefore deserves an
own thread here in the forum.

I want to propose three rules:

1) The @dir attribute represents an "application direction" describing a
direction of travel, for which the element has to be considered. There
are elements with a clear application direction (e.g. <signal>), where
the @dir attribute shall be used, but there are also other elements
without a specific application direction (e.g. <levelCrossing>), where
the @dir attribute shall not be used.

2) In railML 2, even linear elements (e.g. tunnel or bridge) are located
with a single coordinate (and an additional @length attribute). This
coordinate shall always refer to the center of this element and the
value of the @length attribute shall be equally distributed before and
after this location. The @dir attribute shall not be used.

3) For very long linear elements (e.g. Gotthard Base Tunnel), it is
useful to model the element's "portals" instead of its center point. In
that case, elements need to be placed at the begin and the end of the
element oriented towards the center point. The @dir attribute shall be
used to describe the orientation of the "portal", e.g. to define what is
in the tunnel and what is outside the tunnel.

What do you think about this approach? Do you agree or do you prefer
erasing the third point? Any comment is highly appreciated...

[1] https://www.railml.org/forum/index.php?t=msg&th=655& goto=2179&#msg_2179

Best regards
Christian

--
Christian Rahmig - Infrastructure scheme coordinator
railML.org (Registry of Associations: VR 5750)
Phone Coordinator: +49 173 2714509; railML.org: +49 351 47582911
Altplauen 19h; 01187 Dresden; Germany www.railml.org


Christian Rahmig - Infrastructure scheme coordinator
railML.org (Registry of Associations: VR 5750)
Altplauen 19h; 01187 Dresden; Germany www.railML.org
 
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: Definition of track/stoppingPlace/platform infrastructure vs. timetable
Next Topic: Stopping Place use cases
Goto Forum:
  


Current Time: Thu Apr 09 15:08:28 CEST 2020