Category: NZ Tekonverse -> NZ Rail Maps Technical
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Drawing Outline Rectangles (Boxes) In Gimp
The designers of Gimp are at pains to tell us it is not a drawing tool. Yet it can convert a selection into an outline. So we can for example draw a rectangular selection and make an outline from it. Outlines are useful in the NZ Rail Maps aerial mosaics, where a lot of pixels…
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Install mb-util on Debian
I use a Python script called mb-util to build the mbtiles files for the NZ Rail Maps webmaps site. It takes the raw tiles and builds what is effectively a SQLite database that encapsulates the millions of little tiles into one file, which is much easier to handle for file storage and uploading, although slightly…
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NZRM Webmaps Development Update 2021-03-17 [2]
Part 1 of this series took a look at some of the technical history of developing the webmaps project. This part will discuss some of the present and future challenges in the NZ Rail Maps Webmaps. As the initial stage of putting all of NZ online in the webmaps is nearing completion, attention will soon…
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NZRM Webmaps Development Update 2021-03-17 [1]
One of the features of this blog is that it includes technical posts about the NZ Rail Maps project with which converser.nz blogs are affiliated. These posts are less suitable for a general audience mainly interested in the map content and so are posted on NZTechonverse instead. The NZ Rail Maps live webmaps project is…
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NZ Rail Maps: Spatialite vs Geopackage
In the NZ Rail Maps project, I have preferred in recent years to replace shapefiles with databased formats. When using file based dbms (vs client-server) SQlite stands out as a viable alternative that is extremely well supported with an impeccable reputation. There are a number of SQlite based formats of data for GIS layers. Geopackage…