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Updated Creating shape files in QGIS for map data (markdown)

FinCenturion 2022-11-18 21:46:03 +02:00
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Creating-shape-files-in-QGIS-for-map-data.md

@ -17,7 +17,8 @@ https://en.wikipedia.org/wiki/Map_projection
For DCS you need to know that the DCS maps use a UTM projection (meaning coordinates is measured in meters as opposed to degrees, basically), and we need to find out the UTM tile for the map we are working on.
https://en.wikipedia.org/wiki/Universal_Transverse_Mercator_coordinate_system
Find the correct projection for the map. We already have the center meridian meaning we can figure out the proper UTM projection (https://github.com/pydcs/dcs/blob/master/tools/export_map_projection.py).
### 1.1 Find the correct projection for the map
Through PyDCS we already have the center meridian of the map, meaning we can figure out the proper UTM projection (https://github.com/pydcs/dcs/blob/master/tools/export_map_projection.py).
`CENTRAL_MERIDIANS = {
"caucasus": 33,
@ -30,7 +31,11 @@ Find the correct projection for the map. We already have the center meridian mea
"marianaislands": 147,
}`
We can use this [map](https://www.arcgis.com/apps/View/index.html?appid=7fa64a25efd0420896c3336dc2238475) to check out different UTM zones. Then it is a matter of making a new project in QGIS and setting the project CRS to be this.
We can use this [map](https://www.arcgis.com/apps/View/index.html?appid=7fa64a25efd0420896c3336dc2238475) to check out different UTM zones. By clicking on the UTM tile you see the central projection. The map central projection is not necessarily in the center of the map. In the case of South Atlantic it begun as only the Falklands islands so the projection for the whole map is UTM 21S (S for South hemisphere)
![FindProjection](https://user-images.githubusercontent.com/20801481/202789407-6471dbd5-7b59-4cc6-8ab6-08d004b6ddad.jpg)
Then it is a matter of making a new project in QGIS and setting the project CRS to be this.
![Projection](https://user-images.githubusercontent.com/20801481/189474094-89e78347-23b5-440a-b4b5-44862b472276.JPG)
You can add XYZ tiles from this python script to add in a bunch of online satmap tile layers you can use: https://raw.githubusercontent.com/klakar/QGIS_resources/master/collections/Geosupportsystem/python/qgis_basemaps.py