Yeah, that should sound OK, because as we all know the ocean is blue, but here I mean the ocean is blue on the maps of OpenStreetMap.org. This map uses pre-generated tiles with parts of the world map and using a tool such OpenLayers javascript library you can construct a geo map. The problem is that those tiles are always with blue ocean, as you can see on the picture below:

Well those are generated, how can I change the ocean color?

There is no way to change it, except you modify the .xml file from which those tiles are generated, but so far I haven’t done it.

Since I need a vector (thematic) map, such as this on http://thematicmapping.org/ with geoJSON formated borders I noticed that one you’ve a vector map, there’s no loading of the tiles and thus – no blue color of the ocean. You can see an example here:

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