MM Topo Support 0005

Theme tags within OS MasterMap attribution.

History

• 2011-06-03 Email from Robert Hammond re: Theme tags within OS MasterMap attribution.
• 2011-06-15 Phone call from Robert Hammond re: OS MasterMap translation issues.

Contacts

2011-06-03 Email from Robert Hammond:

Andy, 

I have worked through your topo_allgreen.xml changing the display status, linestyles, and line weighting,
but there are a few display issues that could be resolved by possibly using the  tags within
the xml configuration file.  Two example files that I have run through your translator are:

70406-SS4884-5i18.gz (rural Gower Peninsula) 
70406-SS6394-5c10.gz (Central urban Swansea) 

Riverbanks and Bridges 

One example shown below is from tile SS6797, Beaufort Bridge, but there are several bridges in tile
SS6695 (south east of the Liberty Stadium):

The highlighted pink lines indicate the riverbank underneath the bridge, within the xml file you can set the
'active' tag as on or off but that will obviously affect the whole riverbank.  However within the attribution it
gives a more specific description that maybe we could use to filter out unwanted elements:

Riverbank underneath the bridge (there are two versions of themes depending, I assume, on which duplicate
lines have been removed in map reduction?):

Water 
Or: 
Water 
Roads Tracks And Paths 
Structures 

Riverbank north and south of the bridge: 
Water 
Land 

Also, left of the text 'Beaufort Bridge' is another intersecting line, feature code 10046(covered more in the
section below).  The element specifically across the road has the theme tags of 'Roads Tracks And Paths'
and 'Land' whereas the adjoining element north of this has the tag of just 'Land'.  So ideally we would want
to remove the intersecting elements so that it is more like the image below:  

Feature Code 10046 

The feature code 10046 (general feature, line) is used for paths, dividing walls, and outbuildings, so if you
change the linestyle currently it will affect a wide range of elements.

Outbuildings: 
It would appear that some outbuildings were missed as in the following example from tile SS6595 (some
are highlighted in pink but you can see missed outbuildings in the gardens of the adjoining properties just
to the north:

These are 'theme' tagged with: 
Buildings 
Land 

Path: 
Land 
Roads Tracks And Paths 

Dividing Wall: 
Land 

So in theory, rather than all of these elements being affected by the change in linestyle for example, you
can make the feature code 10046 with the "theme" of buildings and land bold to match other outbuildings,
the "theme" paths can be set to a dashed line, and the dividing walls can remain as they are in the image
above.

Departed/added elements that appear in the same location 
I have noticed after the updates have been run, there are numerous examples where an element/text has
been coloured red for removal but the exact same element/text coloured green for adding.  I assume that
some of it is where OS have changed the attribution in the background but some such as the text
"Mean High Water" in tile SS5184 from 70406-SS4884-5i18.gz I would imagine are pretty static in attribution
changes.  Is there any way we can ignore or reduce some of these "changes"?

Invalid Character Translation 
I don't know if Derek mentioned to you about the following issue where the translator has a problem with
particular character, this one is in tile SS5992 from 70406-SS5889-5i12.gz:

The entry in the xml is:
Cilâ 

Regards, 

Rob Hammond 

2011-06-15 Phone call from Robert Hammond:

[..]

4. Feature code and theme issues - see WPD Support 0002:
Rob's main issue was when trying to remove features such a bridges from roads. The feature
code alone is not enough - the themes that exist in the OS MasterMap XML would also be
required. ADK explained that this functionality is not available in current translator - but if
required this could be changed.

[..]