foss4g qgis qgis3 map-projections
Orthographic projection maps are great. They have that “global” feel to them since they look like globes which is useful when you want to evoke a sense of “global context” in your map. They also do wonders for emphasizing and highlighting a part of the map especially if you put it in the center and give it a different color than the rest of your map.
Just look at the image above. What’s the first thing you notice? The Philippines, right?
So how do we create globe-like orthogoraphic projection maps in QGIS? Turns out, it’s pretty straightforward. We just have to define a custom Coordinate Reference System. For example, if I want to create a map like the one above, here’s what I’d do:
Download a World Borders dataset like this from thematicmapping.org.
You can define custom Coordinate Reference Systems (CRS) in QGIS by going to Settings -> Custom Projections
.
The projection definition that we’ll use is shown below:
+proj=ortho +lat_0=13.5 +lon_0=121.9 +x_0=0 +y_0=0 +a=6371000 +b=6371000 +units=m +no_defs
We are basically defining an orthographic projection centered at 13.5 degrees latitude and 121.9 degrees longitude. That coordinate approximates the center of the Philippines (Hello Balanacan Island!).
If you want to center the map somewhere else, you can just replace 13.5 and 121.9 with the corresponding latitude and longitude values where you want to center your map.
Let’s name our Custom CRS as Globe - PHL and click OK.
Next, we just change the current CRS of our project to that of the custom CRS we just defined.
After clicking OK, we should see the following result:
The last step is just to change the style of the map to highlight the Philippines.
You can do this by using a Categorized Symbology
on the NAME
column like below:
And that’s it! You’ve created a globe-like map in QGIS! :)
foss4g foss4gph qgis gis presentation
foss foss4g opensource freeasinfreedom freesoftware
foss4g foss4gph thesis uaap mapping the geography of the uaap spatial analytics basketball basketball analytics
foss4g foss4gph qgis gis presentation
If you find my website or any of the materials I share useful, you can consider donating to the cause below.
Except when explicitly stated otherwise, this work and its contents by Ben Hur S. Pintor is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Other works (software, source code, etc.) referenced in this website are under their own respective licenses.
This site is powered by Jekyll and hosted on Github (view source)