For @ozanyusufoglu
Some polygons (shown in yellow) have an inverse winding order.
Built with blockbuilder.org
forked from ozanyusufoglu's block: winding problem
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<head>
<meta charset="utf-8">
<script src="https://d3js.org/d3.v4.min.js"></script>
<style>
body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
</style>
</head>
<body>
<script>
var width = 960,
height = 500;
var svg = d3.select('body')
.append('svg')
.attr('width', width)
.attr('height', height);
d3.json('istanbul.geojson', function(error,json) {
var projection = d3.geoMercator();
var path = d3.geoPath().projection(projection)
json.features.forEach(item => {
if (d3.geoArea(item)> 2 * Math.PI) {
item.geometry.coordinates = item.geometry.coordinates.map(f => f.map(e => e.reverse()));
item.properties.error = true;
}
})
projection.fitExtent([[0,0],[width,height]], json);
svg.selectAll("path").data(json.features)
.enter()
.append("path")
.style("fill", d => d.properties.error ? "yellow" : "lightblue")
.style("stroke","black")
.style('opacity', '0.1')
.style("stroke-width","2")
.attr("d", path)
})
</script>
</body>
https://d3js.org/d3.v4.min.js