Messages posted here can also be received as emails: information pre-print options:     

Templot Club Home list recently active topics
  Search  Image Gallery  My Account  Members  Help       


 
Forums and resources for users of Templot track design software about Templot Club

Please click: important information for new members and first-time visitors.
 
quick links: files, photos and messages archive on Yahoo
A single message from topic:  Direct loading of background maps   in forum:  Templot talk
main Templot web site

Single message by Martin Wynne       Topic: Direct loading of background maps
Posted: 1 Aug 2017 02:17
 PM  Reply with quote  Reply blank  Go to topic 
Martin Wynne
West Of The Severn, United Kingdom



view images in gallery
view images as slides
A further update.

I'm so pleased with the way this is looking that I have had a rush of blood to the head and now also purchased a subscription for Templot to the 6-inch maps. :)



In truth the 6-inch maps are too small-scale to be much help with detailed track planning, such as identifying the size of turnouts, etc. But they are the only historic maps currently available GB-wide, and available on subscription from the tile server.

The NLS 25-inch project has not yet covered the whole of GB (and may never do so for all areas), and the maps are not currently available on subscription, so cannot be directly loaded in Templot -- you must make your own screenshots from the NLS web site.

Here is a direct comparison between the two (Tewkesbury):

6-inch map:



25-inch map:



Clearly the 6-inch map is not going to be much help in the finer track details (or even the exact number of sidings), but it does show the ruling radii, correct positions of bridges, goods sheds, signal boxes, etc. So it is still useful, and could be used to correctly scale a 25-inch map over the top of it if the latter is set to transparent.

Talking of which, I have also included a function to perform the scaling for manually created screenshots, using the same maths as for the directly loaded ones.

For those adept with a calculator, here it is:

image width in mm =

   513592.631 x COS(latitude) x pixels x scale / 2^zoom

where

513592.631 is a magic number derived from the circumference of the Earth at the Equator.

latitude is at the centre of the map area, e.g. 52.1234 degrees

pixels is the width of the image in pixels, e.g. 1280

scale is your model scale in mm/ft, e.g. 4

zoom is the zoom level of the map, e.g. typically in the range 17-21 for our purposes,
          where zoom=0 means a map of the entire world.

Fortunately if you get zoom wrong it causes the width to double or halve for each step, so it is fairly obvious to correct.

Here is how to find the information in a typical URL:

maps.nls.uk/geo/explore/#zoom=18&lat=51.9959&lon=-2.1498&layers=6&b=3

p.s. 2^zoom means 2zoom   i.e. 2 raised to the power zoom

regards,

Martin.


A single message from topic:  Direct loading of background maps   in forum:  Templot talk
about Templot Club

list recently active topics Templot Companion live online chat Please click: important information for new members and first-time visitors.

Please read this important note about copyright: Unless stated otherwise, all the files submitted to this web site are copyright and the property of the respective contributor. You are welcome to use them for your own personal non-commercial purposes. If you want to re-publish any of this material or use it commercially, you must first obtain the owner's permission to do so.

The small print: All material submitted to this web site is the responsibility of the respective contributor. By submitting material to this web site you acknowledge that you accept full responsibility for the material submitted. The owner of this web site is not responsible for any content displayed here other than his own contributions. The owner of this web site may edit, modify or remove any content at any time without giving notice or reason.
Problems with this web site? Contact webmaster@templot.com.
Powered by UltraBB - © 2009 Data 1 Systems