New Zealand Rail Maps Project Development Report – September 2021

Good morning and welcome to the project development report for September 2021. In the past month, the main focus has shifted to the North Island Main Trunk volume, Volume 2. When this is completed it is expected to become the first volume that will appear on the NZ Rail Maps Volumes site. The Volumes site is being redeveloped so that it will use bog standard PHP that is easy to maintain and does not require any proprietary plugins that have to be paid for to maintain. Understandably it competes for resources with all other aspects of the project, and is therefore progressing slowly as time permits.

Because all of the effort is going into Volume 2 itself, with also some general updates to other volumes on an ad-hoc basis, the Webmaps have not been updated on a regular schedule. The expectation at this stage is Webmaps won’t be updated more than monthly, and possibly three monthly. The Webmaps site still does need a general redesign and to have some additional user functionality added. The main new content will be changes to yard layouts as they are updated, and historical aerial photos. A system for enabling the automated creation of aerial photo tiles has been designed and is gradually being implemented across all volumes. It is hoped when Volume 2 is ready with the static maps for the Volumes site, that at the same time, its aerial photo layers will also be ready for upload onto the Webmaps site. The main benefit of having aerial photos incorporated into the Webmaps site is that the user can choose any zoom level they want and therefore zoom into the photos in as much detail as is available in the original photos (subject to any loss of quality that may occur in the mosaicing process). Whereas in the Volumes, the detail level available is fixed depending on what was chosen for a particular map, and zooming in each map will just get jaggies. Of course, the Webmaps site also allows the user to choose which overlays to display, instead of being limited by, again, what is chosen to be displayed on the fixed Volumes views.

Behind the screens there have been further changes in the semi-automated scripting system used to generate the maps in the GIS. The main alteration is to make a wider range of aerial layers available for Volumes. There will still be a limited number of bands in the Webmaps site which is necessary both for ease of design and maintenance, and for ease of use by giving the user fewer backgrounds. If these bands were not being used it would take too long for the user to have to step through the range of different years available to see what is available for the area they are viewing, because it is not realistically possible to design the site to change the available list of base layers dynamically at this time. Therefore grouping half decade layer ranges as is currently implemented in the drop down menu and in future will be implemented as a slider, is the best option to make the Webmaps site easier to use, but it means that in some cases, not the same range of aerial backgrounds as is available in Volumes will be displayable. For example, if there is a half decade 1970-1974, as is currently defined, if a region has aerial coverage for both 1970 and 1973, only one of these will be included in the 1970-1974 band. This scripting system will be extended with an automated process to produce the XYZ tiles for the Webmaps site as part of the development of aerial layers for addition to the Webmaps so it is hoped to see these coming in for Volume 2 as mentioned above, by the end of 2021. It is also hoped that Volume 2 will be completed for Volumes by then.

Another step this month is to add a new Facebook group to facilitate discussion around the NZ Rail Maps project. Although this has been done in the past, previous groups have been limited to NZ Rail Maps, whereas the new group is open to any kind of discussion about railways in NZ, as the intention is to work with a wider range of members’ interests. The group can be seen linked from the Facebook page of NZ Rail Maps. The option of using groups.io for an email based list is being considered, either by a new group or changing the existing NZ Rail Maps list. One issue is that groups.io now limits Basic groups to a maximum of 100 members, although this might be suitable for the group since relatively few people choose an email based list these days.

Various parts of Volumes have been produced, including NIMT, MSL and NAL, and are available from the project’s Facebook page, which is being used as an interim publishing system until the Volumes site is ready.