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aourednik / historical-basemaps

Collection of georeferenced boundaries of world countries and cultural regions for use in mapping historical data on global or continental scale
GNU General Public License v3.0
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make sure that bordering countries don't have the same color #6

Closed lennertVanSever closed 3 years ago

lennertVanSever commented 3 years ago

First of all, thanks for publishing these maps, it helped me a lot with a side-project that I'm working on :) I had an issue that in my side-project, countries bordering each other could have the same color which is confusing. I fixed this by calculating the bordering country of every country. For example, now the dutch east indies have two bordering countries, Papua New Guinea and Malaya. Based on this data, I released a graph coloring algorithm on the countries and calculated the BORDER_COLOR_INDEX. This index can then be used to assign a color to a country.

{
  "type": "Feature",
  "properties": {
    "AREA": 655357.689,
    "NAME": "Dutch East Indies",
    ...
    "BORDERING": [
      "Papua New Guinea",
      "Malaya"
    ],
    "BORDER_COLOR_INDEX": 1
  }
  ....
}

Apologies for not maintaining the same JSON indentation, I couldn't find an easy way to keep it the same. I was also not able to generate the other png files.