When I look up the specs of GeoJson I see that circles are supported:
http://geopriv.dreamhosters.com/geojson/geojson-spec.html#circleExample
When I try out the code in geojsonlint (http://geojsonlint.com/) however, it gives me an error.
Input:
{
"type": "Circle",
"coordinates": [4.884, 52.353],
"radius": 200
}
Gives:
"Circle" is not a valid GeoJSON type.
I want to show different places of interests with a range of influence on a map by using d3. It needs GeoJson for input but it is true that circles are not supported with GeoJson?
When I look up the specs of GeoJson I see that circles are supported
They aren't. Seems you managed to find some fake or incorrect specs. Go to geojson.org to find the specs, there's nothing about circles.